CODES

ADOPTS WITHOUT AMENDMENTS:

International Fuel Gas Code 2009 (IFGC 2009)

Copyright

Preface

Effective Use of the International Fuel Gas Code

Ordinance

Chapter 1 Scope and Administration

Chapter 2 Definitions

Chapter 3 General Regulations

Chapter 4 Gas Piping Installations

Chapter 5 Chimneys and Vents

Chapter 6 Specific Appliances, Fireplaces and Solid Fuel-Burning Equipment

Chapter 7 Gaseous Hydrogen Systems

Chapter 8 Referenced Standards

Appendix A Sizing and Capacities of Gas Piping (IFGS)

Appendix B Sizing of Venting Systems Serving Appliances Equipped With Draft Hoods, Category I Appliances and Appliances Listed for Use With Type B Vents (IFGS)

Appendix C Exit Terminals of Mechanical Draft and Direct-Vent Venting Systems (IFGS)

Appendix D Recommended Procedure for Safety Inspection of an Existing Appliance Installation (IFGS)

This chapter shall govern the design, installation, modification and maintenance of piping systems. The applicability of this code to piping systems extends from the point of delivery to the connections with the appliances and includes the design, materials, components, fabrication, assembly, installation, testing, inspection, operation and maintenance of such piping systems.
Utility service piping located within buildings shall be installed in accordance with the structural safety and fire protection provisions of the International Building Code.
The storage system for liquefied petroleum gas shall be designed and installed in accordance with the International Fire Code and NFPA 58.
In modifying or adding to existing piping systems, sizes shall be maintained in accordance with this chapter.
Where an additional appliance is to be served, the existing piping shall be checked to determine if it has adequate capacity for all appliances served. If inadequate, the existing system shall be enlarged as required or separate piping of adequate capacity shall be provided.
For other than steel pipe, exposed piping shall be identified by a yellow label marked “Gas” in black letters. The marking shall be spaced at intervals not exceeding 5 feet (1524 mm). The marking shall not be required on pipe located in the same room as the appliance served.
Where two or more meters are installed on the same premises but supply separate consumers, the piping systems shall not be interconnected on the outlet side of the meters.
Piping from multiple meter installations shall be marked with an approved permanent identification by the installer so that the piping system supplied by each meter is readily identifiable.
All pipe utilized for the installation, extension and alteration of any piping system shall be sized to supply the full number of outlets for the intended purpose and shall be sized in accordance with Section 402.
Piping systems shall be of such size and so installed as to provide a supply of gas sufficient to meet the maximum demand and supply gas to each appliance inlet at not less than the minimum supply pressure required by the appliance.

The volume of gas to be provided, in cubic feet per hour, shall be determined directly from the manufacturer’s input ratings of the appliances served. Where an input rating is not indicated, the gas supplier, appliance manufacturer or a qualified agency shall be contacted, or the rating from Table 402.2 shall be used for estimating the volume of gas to be supplied.

The total connected hourly load shall be used as the basis for pipe sizing, assuming that all appliances could be operating at full capacity simultaneously. Where a diversity of load can be established, pipe sizing shall be permitted to be based on such loads.

TABLE 402.2
APPROXIMATE GAS INPUT FOR TYPICAL APPLIANCES

APPLIANCE

INPUT BTU/H
(Approx.)

Space Heating Units

Hydronic boiler

Single family

100,000

Multifamily, per unit

60,000

Warm-air furnace

Single family

100,000

Multifamily, per unit

60,000

Space and Water Heating Units

Hydronic boiler

Single family

120,000

Multifamily, per unit

75,000

Water Heating Appliances

Water heater, automatic instantaneous

Capacity at 2 gal./minute

142,800

Capacity at 4 gal./minute

285,000

Capacity at 6 gal./minute

428,400

Water heater, automatic storage, 30- to 40-gal. tank

35,000

Water heater, automatic storage, 50-gal. tank

50,000

Water heater, domestic, circulating or side-arm

35,000

Cooking Appliances

Built-in oven or broiler unit, domestic

25,000

Built-in top unit, domestic

40,000

Range, free-standing, domestic

65,000

Other Appliances

Barbecue

40,000

Clothes dryer, Type 1 (domestic)

35,000

Gas fireplace, direct-vent

40,000

Gas light

2,500

Gas log

80,000

Refrigerator

3,000

For SI: 1 British thermal unit per hour = 0.293 W, 1 gallon = 3.785 L,
1 gallon per minute = 3.785 L/m.

Gas piping shall be sized in accordance with one of the following:

1. Pipe sizing tables or sizing equations in accordance with Section 402.4.

2. The sizing tables included in a listed piping system’s manufacturer’s installation instructions.

3. Other approved engineering methods.

Where Tables 402.4(1) through 402.4(35) are used to size piping or tubing, the pipe length shall be determined in accordance with Section 402.4.1, 402.4.2 or 402.4.3.

Where Equations 4-1 and 4-2 are used to size piping or tubing, the pipe or tubing shall have smooth inside walls and the pipe length shall be determined in accordance with Section 402.4.1, 402.4.2 or 402.4.3.

1. Low-pressure gas equation [Less than 11/2 pounds per square inch (psi) (10.3 kPa)]:

(Equation 4-1)


2. High-pressure gas equation [11/2 psi (10.3 kPa) and above]:

(Equation 4-2)


where:

D = Inside diameter of pipe, inches (mm).

Q = Input rate appliance(s), cubic feet per hour at 60°F (16°C) and 30-inch mercury column.

P1 = Upstream pressure, psia (P1 + 14.7).

P2 = Downstream pressure, psia (P2 + 14.7).

L = Equivalent length of pipe, feet.

DH = Pressure drop, inch water column
(27.7 inch water column = 1 psi).

TABLE 402.4
Cr AND Y VALUES FOR NATURAL GAS AND
UNDILUTED PROPANE AT STANDARD CONDITIONS

GAS

EQUATION FACTORS

Cr

Y

Natural gas

0.6094

0.9992

Undiluted propane

1.2462

0.9910

For SI: 1 cubic foot = 0.028 m3, 1 foot = 305 mm, 1-inch water column =
0.2488 kPa, 1 pound per square inch = 6.895 kPa, 1 British thermal
unit per hour = 0.293 W.

TABLE 402.4(1)
SCHEDULE 40 METALLIC PIPE

Gas

Natural

Inlet Pressure

Less than 2 psi

Pressure Drop

0.3 in. w.c.

Specific Gravity

0.60

PIPE SIZE (inch)

Nominal

1/2

3/4

1

11/4

11/2

2

21/2

3

4

5

6

8

10

12

Actual ID

0.622

0.824

1.049

1.380

1.610

2.067

2.469

3.068

4.026

5.047

6.065

7.981

10.020

11.938

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

131

273

514

1,060

1,580

3,050

4,860

8,580

17,500

31,700

51,300

105,000

191,000

303,000

20

90

188

353

726

1,090

2,090

3,340

5,900

12,000

21,800

35,300

72,400

132,000

208,000

30

72

151

284

583

873

1,680

2,680

4,740

9,660

17,500

28,300

58,200

106,000

167,000

40

62

129

243

499

747

1,440

2,290

4,050

8,270

15,000

24,200

49,800

90,400

143,000

50

55

114

215

442

662

1,280

2,030

3,590

7,330

13,300

21,500

44,100

80,100

127,000

60

50

104

195

400

600

1,160

1,840

3,260

6,640

12,000

19,500

40,000

72,600

115,000

70

46

95

179

368

552

1,060

1,690

3,000

6,110

11,100

17,900

36,800

66,800

106,000

80

42

89

167

343

514

989

1,580

2,790

5,680

10,300

16,700

34,200

62,100

98,400

90

40

83

157

322

482

928

1,480

2,610

5,330

9,650

15,600

32,100

58,300

92,300

100

38

79

148

304

455

877

1,400

2,470

5,040

9,110

14,800

30,300

55,100

87,200

125

33

70

131

269

403

777

1,240

2,190

4,460

8,080

13,100

26,900

48,800

77,300

150

30

63

119

244

366

704

1,120

1,980

4,050

7,320

11,900

24,300

44,200

70,000

175

28

58

109

224

336

648

1,030

1,820

3,720

6,730

10,900

22,400

40,700

64,400

200

26

54

102

209

313

602

960

1,700

3,460

6,260

10,100

20,800

37,900

59,900

250

23

48

90

185

277

534

851

1,500

3,070

5,550

8,990

18,500

33,500

53,100

300

21

43

82

168

251

484

771

1,360

2,780

5,030

8,150

16,700

30,400

48,100

350

19

40

75

154

231

445

709

1,250

2,560

4,630

7,490

15,400

28,000

44,300

400

18

37

70

143

215

414

660

1,170

2,380

4,310

6,970

14,300

26,000

41,200

450

17

35

66

135

202

389

619

1,090

2,230

4,040

6,540

13,400

24,400

38,600

500

16

33

62

127

191

367

585

1,030

2,110

3,820

6,180

12,700

23,100

36,500

550

15

31

59

121

181

349

556

982

2,000

3,620

5,870

12,100

21,900

34,700

600

14

30

56

115

173

333

530

937

1,910

3,460

5,600

11,500

20,900

33,100

650

14

29

54

110

165

318

508

897

1,830

3,310

5,360

11,000

20,000

31,700

700

13

27

52

106

159

306

488

862

1,760

3,180

5,150

10,600

19,200

30,400

750

13

26

50

102

153

295

470

830

1,690

3,060

4,960

10,200

18,500

29,300

800

12

26

48

99

148

285

454

802

1,640

2,960

4,790

9,840

17,900

28,300

850

12

25

46

95

143

275

439

776

1,580

2,860

4,640

9,530

17,300

27,400

900

11

24

45

93

139

267

426

752

1,530

2,780

4,500

9,240

16,800

26,600

950

11

23

44

90

135

259

413

731

1,490

2,700

4,370

8,970

16,300

25,800

1,000

11

23

43

87

131

252

402

711

1,450

2,620

4,250

8,720

15,800

25,100

1,100

10

21

40

83

124

240

382

675

1,380

2,490

4,030

8,290

15,100

23,800

1,200

NA

20

39

79

119

229

364

644

1,310

2,380

3,850

7,910

14,400

22,700

1,300

NA

20

37

76

114

219

349

617

1,260

2,280

3,680

7,570

13,700

21,800

1,400

NA

19

35

73

109

210

335

592

1,210

2,190

3,540

7,270

13,200

20,900

1,500

NA

18

34

70

105

203

323

571

1,160

2,110

3,410

7,010

12,700

20,100

1,600

NA

18

33

68

102

196

312

551

1,120

2,030

3,290

6,770

12,300

19,500

1,700

NA

17

32

66

98

189

302

533

1,090

1,970

3,190

6,550

11,900

18,800

1,800

NA

16

31

64

95

184

293

517

1,050

1,910

3,090

6,350

11,500

18,300

1,900

NA

16

30

62

93

178

284

502

1,020

1,850

3,000

6,170

11,200

17,700

2,000

NA

16

29

60

90

173

276

488

1,000

1,800

2,920

6,000

10,900

17,200

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. NA means a flow of less than 10 cfh.

2. All table entries have been rounded to three significant digits.

TABLE 402.4(2)
SCHEDULE 40 METALLIC PIPE

Gas

Natural

Inlet Pressure

Less than 2 psi

Pressure Drop

0.5 in. w.c.

Specific Gravity

0.60

PIPE SIZE (inch)

Nominal

1/2

3/4

1

11/4

11/2

2

21/2

3

4

5

6

8

10

12

Actual ID

0.622

0.824

1.049

1.380

1.610

2.067

2.469

3.068

4.026

5.047

6.065

7.981

10.020

11.938

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

172

360

678

1,390

2,090

4,020

6,400

11,300

23,100

41,800

67,600

139,000

252,000

399,000

20

118

247

466

957

1,430

2,760

4,400

7,780

15,900

28,700

46,500

95,500

173,000

275,000

30

95

199

374

768

1,150

2,220

3,530

6,250

12,700

23,000

37,300

76,700

139,000

220,000

40

81

170

320

657

985

1,900

3,020

5,350

10,900

19,700

31,900

65,600

119,000

189,000

50

72

151

284

583

873

1,680

2,680

4,740

9,660

17,500

28,300

58,200

106,000

167,000

60

65

137

257

528

791

1,520

2,430

4,290

8,760

15,800

25,600

52,700

95,700

152,000

70

60

126

237

486

728

1,400

2,230

3,950

8,050

14,600

23,600

48,500

88,100

139,000

80

56

117

220

452

677

1,300

2,080

3,670

7,490

13,600

22,000

45,100

81,900

130,000

90

52

110

207

424

635

1,220

1,950

3,450

7,030

12,700

20,600

42,300

76,900

122,000

100

50

104

195

400

600

1,160

1,840

3,260

6,640

12,000

19,500

40,000

72,600

115,000

125

44

92

173

355

532

1,020

1,630

2,890

5,890

10,600

17,200

35,400

64,300

102,000

150

40

83

157

322

482

928

1,480

2,610

5,330

9,650

15,600

32,100

58,300

92,300

175

37

77

144

296

443

854

1,360

2,410

4,910

8,880

14,400

29,500

53,600

84,900

200

34

71

134

275

412

794

1,270

2,240

4,560

8,260

13,400

27,500

49,900

79,000

250

30

63

119

244

366

704

1,120

1,980

4,050

7,320

11,900

24,300

44,200

70,000

300

27

57

108

221

331

638

1,020

1,800

3,670

6,630

10,700

22,100

40,100

63,400

350

25

53

99

203

305

587

935

1,650

3,370

6,100

9,880

20,300

36,900

58,400

400

23

49

92

189

283

546

870

1,540

3,140

5,680

9,190

18,900

34,300

54,300

450

22

46

86

177

266

512

816

1,440

2,940

5,330

8,620

17,700

32,200

50,900

500

21

43

82

168

251

484

771

1,360

2,780

5,030

8,150

16,700

30,400

48,100

550

20

41

78

159

239

459

732

1,290

2,640

4,780

7,740

15,900

28,900

45,700

600

19

39

74

152

228

438

699

1,240

2,520

4,560

7,380

15,200

27,500

43,600

650

18

38

71

145

218

420

669

1,180

2,410

4,360

7,070

14,500

26,400

41,800

700

17

36

68

140

209

403

643

1,140

2,320

4,190

6,790

14,000

25,300

40,100

750

17

35

66

135

202

389

619

1,090

2,230

4,040

6,540

13,400

24,400

38,600

800

16

34

63

130

195

375

598

1,060

2,160

3,900

6,320

13,000

23,600

37,300

850

16

33

61

126

189

363

579

1,020

2,090

3,780

6,110

12,600

22,800

36,100

900

15

32

59

122

183

352

561

992

2,020

3,660

5,930

12,200

22,100

35,000

950

15

31

58

118

178

342

545

963

1,960

3,550

5,760

11,800

21,500

34,000

1,000

14

30

56

115

173

333

530

937

1,910

3,460

5,600

11,500

20,900

33,100

1,100

14

28

53

109

164

316

503

890

1,810

3,280

5,320

10,900

19,800

31,400

1,200

13

27

51

104

156

301

480

849

1,730

3,130

5,070

10,400

18,900

30,000

1,300

12

26

49

100

150

289

460

813

1,660

3,000

4,860

9,980

18,100

28,700

1,400

12

25

47

96

144

277

442

781

1,590

2,880

4,670

9,590

17,400

27,600

1,500

11

24

45

93

139

267

426

752

1,530

2,780

4,500

9,240

16,800

26,600

1,600

11

23

44

89

134

258

411

727

1,480

2,680

4,340

8,920

16,200

25,600

1,700

11

22

42

86

130

250

398

703

1,430

2,590

4,200

8,630

15,700

24,800

1,800

10

22

41

84

126

242

386

682

1,390

2,520

4,070

8,370

15,200

24,100

1,900

10

21

40

81

122

235

375

662

1,350

2,440

3,960

8,130

14,800

23,400

2,000

NA

20

39

79

119

229

364

644

1,310

2,380

3,850

7,910

14,400

22,700

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. NA means a flow of less than 10 cfh.

2. All table entries have been rounded to three significant digits.

TABLE 402.4(3)
SCHEDULE 40 METALLIC PIPE

Gas

Natural

Inlet Pressure

2.0 psi

Pressure Drop

1.0 psi

Specific Gravity

0.60

PIPE SIZE (inch)

Nominal

1/2

3/4

1

11/4

11/2

2

21/2

3

4

Actual ID

0.622

0.824

1.049

1.380

1.610

2.067

2.469

3.068

4.026

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

1,510

3,040

5,560

11,400

17,100

32,900

52,500

92,800

189,000

20

1,070

2,150

3,930

8,070

12,100

23,300

37,100

65,600

134,000

30

869

1,760

3,210

6,590

9,880

19,000

30,300

53,600

109,000

40

753

1,520

2,780

5,710

8,550

16,500

26,300

46,400

94,700

50

673

1,360

2,490

5,110

7,650

14,700

23,500

41,500

84,700

60

615

1,240

2,270

4,660

6,980

13,500

21,400

37,900

77,300

70

569

1,150

2,100

4,320

6,470

12,500

19,900

35,100

71,600

80

532

1,080

1,970

4,040

6,050

11,700

18,600

32,800

67,000

90

502

1,010

1,850

3,810

5,700

11,000

17,500

30,900

63,100

100

462

934

1,710

3,510

5,260

10,100

16,100

28,500

58,200

125

414

836

1,530

3,140

4,700

9,060

14,400

25,500

52,100

150

372

751

1,370

2,820

4,220

8,130

13,000

22,900

46,700

175

344

695

1,270

2,601

3,910

7,530

12,000

21,200

43,300

200

318

642

1,170

2,410

3,610

6,960

11,100

19,600

40,000

250

279

583

1,040

2,140

3,210

6,180

9,850

17,400

35,500

300

253

528

945

1,940

2,910

5,600

8,920

15,800

32,200

350

232

486

869

1,790

2,670

5,150

8,210

14,500

29,600

400

216

452

809

1,660

2,490

4,790

7,640

13,500

27,500

450

203

424

759

1,560

2,330

4,500

7,170

12,700

25,800

500

192

401

717

1,470

2,210

4,250

6,770

12,000

24,400

550

182

381

681

1,400

2,090

4,030

6,430

11,400

23,200

600

174

363

650

1,330

2,000

3,850

6,130

10,800

22,100

650

166

348

622

1,280

1,910

3,680

5,870

10,400

21,200

700

160

334

598

1,230

1,840

3,540

5,640

9,970

20,300

750

154

322

576

1,180

1,770

3,410

5,440

9,610

19,600

800

149

311

556

1,140

1,710

3,290

5,250

9,280

18,900

850

144

301

538

1,100

1,650

3,190

5,080

8,980

18,300

900

139

292

522

1,070

1,600

3,090

4,930

8,710

17,800

950

135

283

507

1,040

1,560

3,000

4,780

8,460

17,200

1,000

132

275

493

1,010

1,520

2,920

4,650

8,220

16,800

1,100

125

262

468

960

1,440

2,770

4,420

7,810

15,900

1,200

119

250

446

917

1,370

2,640

4,220

7,450

15,200

1,300

114

239

427

878

1,320

2,530

4,040

7,140

14,600

1,400

110

230

411

843

1,260

2,430

3,880

6,860

14,000

1,500

106

221

396

812

1,220

2,340

3,740

6,600

13,500

1,600

102

214

382

784

1,180

2,260

3,610

6,380

13,000

1,700

99

207

370

759

1,140

2,190

3,490

6,170

12,600

1,800

96

200

358

736

1,100

2,120

3,390

5,980

12,200

1,900

93

195

348

715

1,070

2,060

3,290

5,810

11,900

2,000

91

189

339

695

1,040

2,010

3,200

5,650

11,500

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(4)
SCHEDULE 40 METALLIC PIPE

Gas

Natural

Inlet Pressure

3.0 psi

Pressure Drop

2.0 psi

Specific Gravity

0.60

PIPE SIZE (inch)

Nominal

1/2

3/4

1

11/4

11/2

2

21/2

3

4

Actual ID

0.622

0.824

1.049

1.380

1.610

2.067

2.469

3.068

4.026

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

2,350

4,920

9,270

19,000

28,500

54,900

87,500

155,000

316,000

20

1,620

3,380

6,370

13,100

19,600

37,700

60,100

106,000

217,000

30

1,300

2,720

5,110

10,500

15,700

30,300

48,300

85,400

174,000

40

1,110

2,320

4,380

8,990

13,500

25,900

41,300

73,100

149,000

50

985

2,060

3,880

7,970

11,900

23,000

36,600

64,800

132,000

60

892

1,870

3,520

7,220

10,800

20,800

33,200

58,700

120,000

70

821

1,720

3,230

6,640

9,950

19,200

30,500

54,000

110,000

80

764

1,600

3,010

6,180

9,260

17,800

28,400

50,200

102,000

90

717

1,500

2,820

5,800

8,680

16,700

26,700

47,100

96,100

100

677

1,420

2,670

5,470

8,200

15,800

25,200

44,500

90,800

125

600

1,250

2,360

4,850

7,270

14,000

22,300

39,500

80,500

150

544

1,140

2,140

4,400

6,590

12,700

20,200

35,700

72,900

175

500

1,050

1,970

4,040

6,060

11,700

18,600

32,900

67,100

200

465

973

1,830

3,760

5,640

10,900

17,300

30,600

62,400

250

412

862

1,620

3,330

5,000

9,620

15,300

27,100

55,300

300

374

781

1,470

3,020

4,530

8,720

13,900

24,600

50,100

350

344

719

1,350

2,780

4,170

8,020

12,800

22,600

46,100

400

320

669

1,260

2,590

3,870

7,460

11,900

21,000

42,900

450

300

627

1,180

2,430

3,640

7,000

11,200

19,700

40,200

500

283

593

1,120

2,290

3,430

6,610

10,500

18,600

38,000

550

269

563

1,060

2,180

3,260

6,280

10,000

17,700

36,100

600

257

537

1,010

2,080

3,110

5,990

9,550

16,900

34,400

650

246

514

969

1,990

2,980

5,740

9,150

16,200

33,000

700

236

494

931

1,910

2,860

5,510

8,790

15,500

31,700

750

228

476

897

1,840

2,760

5,310

8,470

15,000

30,500

800

220

460

866

1,780

2,660

5,130

8,180

14,500

29,500

850

213

445

838

1,720

2,580

4,960

7,910

14,000

28,500

900

206

431

812

1,670

2,500

4,810

7,670

13,600

27,700

950

200

419

789

1,620

2,430

4,670

7,450

13,200

26,900

1,000

195

407

767

1,580

2,360

4,550

7,240

12,800

26,100

1,100

185

387

729

1,500

2,240

4,320

6,890

12,200

24,800

1,200

177

369

695

1,430

2,140

4,120

6,570

11,600

23,700

1,300

169

353

666

1,370

2,050

3,940

6,290

11,100

22,700

1,400

162

340

640

1,310

1,970

3,790

6,040

10,700

21,800

1,500

156

327

616

1,270

1,900

3,650

5,820

10,300

21,000

1,600

151

316

595

1,220

1,830

3,530

5,620

10,000

20,300

1,700

146

306

576

1,180

1,770

3,410

5,440

9,610

19,600

1,800

142

296

558

1,150

1,720

3,310

5,270

9,320

19,000

1,900

138

288

542

1,110

1,670

3,210

5,120

9,050

18,400

2,000

134

280

527

1,080

1,620

3,120

4,980

8,800

18,000

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(5)
SCHEDULE 40 METALLIC PIPE

Gas

Natural

Inlet Pressure

5.0 psi

Pressure Drop

3.5 psi

Specific Gravity

0.60

PIPE SIZE (inch)

Nominal

1/2

3/4

1

11/4

11/2

2

21/2

3

4

Actual ID

0.622

0.824

1.049

1.380

1.610

2.067

2.469

3.068

4.026

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

3,190

6,430

11,800

24,200

36,200

69,700

111,000

196,000

401,000

20

2,250

4,550

8,320

17,100

25,600

49,300

78,600

139,000

283,000

30

1,840

3,720

6,790

14,000

20,900

40,300

64,200

113,000

231,000

40

1,590

3,220

5,880

12,100

18,100

34,900

55,600

98,200

200,000

50

1,430

2,880

5,260

10,800

16,200

31,200

49,700

87,900

179,000

60

1,300

2,630

4,800

9,860

14,800

28,500

45,400

80,200

164,000

70

1,200

2,430

4,450

9,130

13,700

26,400

42,000

74,300

151,000

80

1,150

2,330

4,260

8,540

12,800

24,700

39,300

69,500

142,000

90

1,060

2,150

3,920

8,050

12,100

23,200

37,000

65,500

134,000

100

979

1,980

3,620

7,430

11,100

21,400

34,200

60,400

123,000

125

876

1,770

3,240

6,640

9,950

19,200

30,600

54,000

110,000

150

786

1,590

2,910

5,960

8,940

17,200

27,400

48,500

98,900

175

728

1,470

2,690

5,520

8,270

15,900

25,400

44,900

91,600

200

673

1,360

2,490

5,100

7,650

14,700

23,500

41,500

84,700

250

558

1,170

2,200

4,510

6,760

13,000

20,800

36,700

74,900

300

506

1,060

1,990

4,090

6,130

11,800

18,800

33,300

67,800

350

465

973

1,830

3,760

5,640

10,900

17,300

30,600

62,400

400

433

905

1,710

3,500

5,250

10,100

16,100

28,500

58,100

450

406

849

1,600

3,290

4,920

9,480

15,100

26,700

54,500

500

384

802

1,510

3,100

4,650

8,950

14,300

25,200

51,500

550

364

762

1,440

2,950

4,420

8,500

13,600

24,000

48,900

600

348

727

1,370

2,810

4,210

8,110

12,900

22,900

46,600

650

333

696

1,310

2,690

4,030

7,770

12,400

21,900

44,600

700

320

669

1,260

2,590

3,880

7,460

11,900

21,000

42,900

750

308

644

1,210

2,490

3,730

7,190

11,500

20,300

41,300

800

298

622

1,170

2,410

3,610

6,940

11,100

19,600

39,900

850

288

602

1,130

2,330

3,490

6,720

10,700

18,900

38,600

900

279

584

1,100

2,260

3,380

6,520

10,400

18,400

37,400

950

271

567

1,070

2,190

3,290

6,330

10,100

17,800

36,400

1,000

264

551

1,040

2,130

3,200

6,150

9,810

17,300

35,400

1,100

250

524

987

2,030

3,030

5,840

9,320

16,500

33,600

1,200

239

500

941

1,930

2,900

5,580

8,890

15,700

32,000

1,300

229

478

901

1,850

2,770

5,340

8,510

15,000

30,700

1,400

220

460

866

1,780

2,660

5,130

8,180

14,500

29,500

1,500

212

443

834

1,710

2,570

4,940

7,880

13,900

28,400

1,600

205

428

806

1,650

2,480

4,770

7,610

13,400

27,400

1,700

198

414

780

1,600

2,400

4,620

7,360

13,000

26,500

1,800

192

401

756

1,550

2,330

4,480

7,140

12,600

25,700

1,900

186

390

734

1,510

2,260

4,350

6,930

12,300

25,000

2,000

181

379

714

1,470

2,200

4,230

6,740

11,900

24,300

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(6)
SEMIRIGID COPPER TUBING

Gas

Natural

Inlet Pressure

Less than 2 psi

Pressure Drop

0.3 in. w.c.

Specific Gravity

0.60

TUBE SIZE (inch)

Nominal

K & L

1/4

3/8

1/2

5/8

3/4

1

11/4

11/2

2

ACR

3/8

1/2

5/8

3/4

7/8

11/8

13/8

Outside

0.375

0.500

0.625

0.750

0.875

1.125

1.375

1.625

2.125

Inside

0.305

0.402

0.527

0.652

0.745

0.995

1.245

1.481

1.959

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

20

42

85

148

210

448

806

1,270

2,650

20

14

29

58

102

144

308

554

873

1,820

30

11

23

47

82

116

247

445

701

1,460

40

10

20

40

70

99

211

381

600

1,250

50

NA

17

35

62

88

187

337

532

1,110

60

NA

16

32

56

79

170

306

482

1,000

70

NA

14

29

52

73

156

281

443

924

80

NA

13

27

48

68

145

262

413

859

90

NA

13

26

45

64

136

245

387

806

100

NA

12

24

43

60

129

232

366

761

125

NA

11

22

38

53

114

206

324

675

150

NA

10

20

34

48

103

186

294

612

175

NA

NA

18

31

45

95

171

270

563

200

NA

NA

17

29

41

89

159

251

523

250

NA

NA

15

26

37

78

141

223

464

300

NA

NA

13

23

33

71

128

202

420

350

NA

NA

12

22

31

65

118

186

387

400

NA

NA

11

20

28

61

110

173

360

450

NA

NA

11

19

27

57

103

162

338

500

NA

NA

10

18

25

54

97

153

319

550

NA

NA

NA

17

24

51

92

145

303

600

NA

NA

NA

16

23

49

88

139

289

650

NA

NA

NA

15

22

47

84

133

277

700

NA

NA

NA

15

21

45

81

128

266

750

NA

NA

NA

14

20

43

78

123

256

800

NA

NA

NA

14

20

42

75

119

247

850

NA

NA

NA

13

19

40

73

115

239

900

NA

NA

NA

13

18

39

71

111

232

950

NA

NA

NA

13

18

38

69

108

225

1,000

NA

NA

NA

12

17

37

67

105

219

1,100

NA

NA

NA

12

16

35

63

100

208

1,200

NA

NA

NA

11

16

34

60

95

199

1,300

NA

NA

NA

11

15

32

58

91

190

1,400

NA

NA

NA

10

14

31

56

88

183

1,500

NA

NA

NA

NA

14

30

54

84

176

1,600

NA

NA

NA

NA

13

29

52

82

170

1,700

NA

NA

NA

NA

13

28

50

79

164

1,800

NA

NA

NA

NA

13

27

49

77

159

1,900

NA

NA

NA

NA

12

26

47

74

155

2,000

NA

NA

NA

NA

12

25

46

72

151

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

2. NA means a flow of less than 10 cfh.

3. All table entries have been rounded to three significant digits.

TABLE 402.4(7)
SEMIRIGID COPPER TUBING

Gas

Natural

Inlet Pressure

Less than 2 psi

Pressure Drop

0.5 in. w.c.

Specific Gravity

0.60

TUBE SIZE (inch)

Nominal

K & L

1/4

3/8

1/2

5/8

3/4

1

11/4

11/2

2

ACR

3/8

1/2

5/8

3/4

7/8

11/8

13/8

Outside

0.375

0.500

0.625

0.750

0.875

1.125

1.375

1.625

2.125

Inside

0.305

0.402

0.527

0.652

0.745

0.995

1.245

1.481

1.959

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

27

55

111

195

276

590

1,060

1,680

3,490

20

18

38

77

134

190

406

730

1,150

2,400

30

15

30

61

107

152

326

586

925

1,930

40

13

26

53

92

131

279

502

791

1,650

50

11

23

47

82

116

247

445

701

1,460

60

10

21

42

74

105

224

403

635

1,320

70

NA

19

39

68

96

206

371

585

1,220

80

NA

18

36

63

90

192

345

544

1,130

90

NA

17

34

59

84

180

324

510

1,060

100

NA

16

32

56

79

170

306

482

1,000

125

NA

14

28

50

70

151

271

427

890

150

NA

13

26

45

64

136

245

387

806

175

NA

12

24

41

59

125

226

356

742

200

NA

11

22

39

55

117

210

331

690

250

NA

NA

20

34

48

103

186

294

612

300

NA

NA

18

31

44

94

169

266

554

350

NA

NA

16

28

40

86

155

245

510

400

NA

NA

15

26

38

80

144

228

474

450

NA

NA

14

25

35

75

135

214

445

500

NA

NA

13

23

33

71

128

202

420

550

NA

NA

13

22

32

68

122

192

399

600

NA

NA

12

21

30

64

116

183

381

650

NA

NA

12

20

29

62

111

175

365

700

NA

NA

11

20

28

59

107

168

350

750

NA

NA

11

19

27

57

103

162

338

800

NA

NA

10

18

26

55

99

156

326

850

NA

NA

10

18

25

53

96

151

315

900

NA

NA

NA

17

24

52

93

147

306

950

NA

NA

NA

17

24

50

90

143

297

1,000

NA

NA

NA

16

23

49

88

139

289

1,100

NA

NA

NA

15

22

46

84

132

274

1,200

NA

NA

NA

15

21

44

80

126

262

1,300

NA

NA

NA

14

20

42

76

120

251

1,400

NA

NA

NA

13

19

41

73

116

241

1,500

NA

NA

NA

13

18

39

71

111

232

1,600

NA

NA

NA

13

18

38

68

108

224

1,700

NA

NA

NA

12

17

37

66

104

217

1,800

NA

NA

NA

12

17

36

64

101

210

1,900

NA

NA

NA

11

16

35

62

98

204

2,000

NA

NA

NA

11

16

34

60

95

199

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

2. NA means a flow of less than 10 cfh.

3. All table entries have been rounded to three significant digits.

TABLE 402.4(8)
SEMIRIGID COPPER TUBING

Gas

Natural

Inlet Pressure

Less than 2 psi

Pressure Drop

1.0 in. w.c.

Specific Gravity

0.60

INTENDED USE: SIZING BETWEEN HOUSE LINE REGULATOR AND THE APPLIANCE

TUBE SIZE (inch)

Nominal

K & L

1/4

3/8

1/2

5/8

3/4

1

11/4

11/2

2

ACR

3/8

1/2

5/8

3/4

7/8

11/8

13/8

Outside

0.375

0.500

0.625

0.750

0.875

1.125

1.375

1.625

2.125

Inside

0.305

0.402

0.527

0.652

0.745

0.995

1.245

1.481

1.959

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

39

80

162

283

402

859

1,550

2,440

5,080

20

27

55

111

195

276

590

1,060

1,680

3,490

30

21

44

89

156

222

474

853

1,350

2,800

40

18

38

77

134

190

406

730

1,150

2,400

50

16

33

68

119

168

359

647

1,020

2,130

60

15

30

61

107

152

326

586

925

1,930

70

13

28

57

99

140

300

539

851

1,770

80

13

26

53

92

131

279

502

791

1,650

90

12

24

49

86

122

262

471

742

1,550

100

11

23

47

82

116

247

445

701

1,460

125

NA

20

41

72

103

219

394

622

1,290

150

NA

18

37

65

93

198

357

563

1,170

175

NA

17

34

60

85

183

329

518

1,080

200

NA

16

32

56

79

170

306

482

1,000

250

NA

14

28

50

70

151

271

427

890

300

NA

13

26

45

64

136

245

387

806

350

NA

12

24

41

59

125

226

356

742

400

NA

11

22

39

55

117

210

331

690

450

NA

10

21

36

51

110

197

311

647

500

NA

NA

20

34

48

103

186

294

612

550

NA

NA

19

32

46

98

177

279

581

600

NA

NA

18

31

44

94

169

266

554

650

NA

NA

17

30

42

90

162

255

531

700

NA

NA

16

28

40

86

155

245

510

750

NA

NA

16

27

39

83

150

236

491

800

NA

NA

15

26

38

80

144

228

474

850

NA

NA

15

26

36

78

140

220

459

900

NA

NA

14

25

35

75

135

214

445

950

NA

NA

14

24

34

73

132

207

432

1,000

NA

NA

13

23

33

71

128

202

420

1,100

NA

NA

13

22

32

68

122

192

399

1,200

NA

NA

12

21

30

64

116

183

381

1,300

NA

NA

12

20

29

62

111

175

365

1,400

NA

NA

11

20

28

59

107

168

350

1,500

NA

NA

11

19

27

57

103

162

338

1,600

NA

NA

10

18

26

55

99

156

326

1,700

NA

NA

10

18

25

53

96

151

315

1,800

NA

NA

NA

17

24

52

93

147

306

1,900

NA

NA

NA

17

24

50

90

143

297

2,000

NA

NA

NA

16

23

49

88

139

289

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

2. NA means a flow of less than 10 cfh.

3. All table entries have been rounded to three significant digits.

TABLE 402.4(9)
SEMIRIGID COPPER TUBING

Gas

Natural

Inlet Pressure

Less than 2.0 psi

Pressure Drop

17.0 in w.c.

Specific Gravity

0.60

TUBE SIZE (inch)

Nominal

K & L

1/4

3/8

1/2

5/8

3/4

1

11/4

11/2

2

ACR

3/8

1/2

5/8

3/4

7/8

11/8

13/8

Outside

0.375

0.500

0.625

0.750

0.875

1.125

1.375

1.625

2.125

Inside

0.305

0.402

0.527

0.652

0.745

0.995

1.245

1.481

1.959

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

190

391

796

1,390

1,970

4,220

7,590

12,000

24,900

20

130

269

547

956

1,360

2,900

5,220

8,230

17,100

30

105

216

439

768

1,090

2,330

4,190

6,610

13,800

40

90

185

376

657

932

1,990

3,590

5,650

11,800

50

79

164

333

582

826

1,770

3,180

5,010

10,400

60

72

148

302

528

749

1,600

2,880

4,540

9,460

70

66

137

278

486

689

1,470

2,650

4,180

8,700

80

62

127

258

452

641

1,370

2,460

3,890

8,090

90

58

119

243

424

601

1,280

2,310

3,650

7,590

100

55

113

229

400

568

1,210

2,180

3,440

7,170

125

48

100

203

355

503

1,080

1,940

3,050

6,360

150

44

90

184

321

456

974

1,750

2,770

5,760

175

40

83

169

296

420

896

1,610

2,540

5,300

200

38

77

157

275

390

834

1,500

2,370

4,930

250

33

69

140

244

346

739

1,330

2,100

4,370

300

30

62

126

221

313

670

1,210

1,900

3,960

350

28

57

116

203

288

616

1,110

1,750

3,640

400

26

53

108

189

268

573

1,030

1,630

3,390

450

24

50

102

177

252

538

968

1,530

3,180

500

23

47

96

168

238

508

914

1,440

3,000

550

22

45

91

159

226

482

868

1,370

2,850

600

21

43

87

152

215

460

829

1,310

2,720

650

20

41

83

145

206

441

793

1,250

2,610

700

19

39

80

140

198

423

762

1,200

2,500

750

18

38

77

135

191

408

734

1,160

2,410

800

18

37

74

130

184

394

709

1,120

2,330

850

17

35

72

126

178

381

686

1,080

2,250

900

17

34

70

122

173

370

665

1,050

2,180

950

16

33

68

118

168

359

646

1,020

2,120

1,000

16

32

66

115

163

349

628

991

2,060

1,100

15

31

63

109

155

332

597

941

1,960

1,200

14

29

60

104

148

316

569

898

1,870

1,300

14

28

57

100

142

303

545

860

1,790

1,400

13

27

55

96

136

291

524

826

1,720

1,500

13

26

53

93

131

280

505

796

1,660

1,600

12

25

51

89

127

271

487

768

1,600

1,700

12

24

49

86

123

262

472

744

1,550

1,800

11

24

48

84

119

254

457

721

1,500

1,900

11

23

47

81

115

247

444

700

1,460

2,000

11

22

45

79

112

240

432

681

1,420

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

2. All table entries have been rounded to three significant digits.

TABLE 402.4(10)
SEMIRIGID COPPER TUBING

Gas

Natural

Inlet Pressure

2.0 psi

Pressure Drop

1.0 psi

Specific Gravity

0.60

TUBE SIZE (inch)

Nominal

K & L

1/4

3/8

1/2

5/8

3/4

1

11/4

11/2

2

ACR

3/8

1/2

5/8

3/4

7/8

11/8

13/8

Outside

0.375

0.500

0.625

0.750

0.875

1.125

1.375

1.625

2.125

Inside

0.305

0.402

0.527

0.652

0.745

0.995

1.245

1.481

1.959

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

245

506

1,030

1,800

2,550

5,450

9,820

15,500

32,200

20

169

348

708

1,240

1,760

3,750

6,750

10,600

22,200

30

135

279

568

993

1,410

3,010

5,420

8,550

17,800

40

116

239

486

850

1,210

2,580

4,640

7,310

15,200

50

103

212

431

754

1,070

2,280

4,110

6,480

13,500

60

93

192

391

683

969

2,070

3,730

5,870

12,200

70

86

177

359

628

891

1,900

3,430

5,400

11,300

80

80

164

334

584

829

1,770

3,190

5,030

10,500

90

75

154

314

548

778

1,660

2,990

4,720

9,820

100

71

146

296

518

735

1,570

2,830

4,450

9,280

125

63

129

263

459

651

1,390

2,500

3,950

8,220

150

57

117

238

416

590

1,260

2,270

3,580

7,450

175

52

108

219

383

543

1,160

2,090

3,290

6,850

200

49

100

204

356

505

1,080

1,940

3,060

6,380

250

43

89

181

315

448

956

1,720

2,710

5,650

300

39

80

164

286

406

866

1,560

2,460

5,120

350

36

74

150

263

373

797

1,430

2,260

4,710

400

33

69

140

245

347

741

1,330

2,100

4,380

450

31

65

131

230

326

696

1,250

1,970

4,110

500

30

61

124

217

308

657

1,180

1,870

3,880

550

28

58

118

206

292

624

1,120

1,770

3,690

600

27

55

112

196

279

595

1,070

1,690

3,520

650

26

53

108

188

267

570

1,030

1,620

3,370

700

25

51

103

181

256

548

986

1,550

3,240

750

24

49

100

174

247

528

950

1,500

3,120

800

23

47

96

168

239

510

917

1,450

3,010

850

22

46

93

163

231

493

888

1,400

2,920

900

22

44

90

158

224

478

861

1,360

2,830

950

21

43

88

153

217

464

836

1,320

2,740

1,000

20

42

85

149

211

452

813

1,280

2,670

1,100

19

40

81

142

201

429

772

1,220

2,540

1,200

18

38

77

135

192

409

737

1,160

2,420

1,300

18

36

74

129

183

392

705

1,110

2,320

1,400

17

35

71

124

176

376

678

1,070

2,230

1,500

16

34

68

120

170

363

653

1,030

2,140

1,600

16

33

66

116

164

350

630

994

2,070

1,700

15

31

64

112

159

339

610

962

2,000

1,800

15

30

62

108

154

329

592

933

1,940

1,900

14

30

60

105

149

319

575

906

1,890

2,000

14

29

59

102

145

310

559

881

1,830

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

2. All table entries have been rounded to three significant digits.

TABLE 402.4(11)
SEMIRIGID COPPER TUBING

Gas

Natural

Inlet Pressure

2.0 psi

Pressure Drop

1.5 psi

Specific Gravity

0.60

INTENDED USE

Pipe sizing between point of delivery and the house line regulator.
Total load supplied by a single house line regulator not exceeding 150 cubic feet per hour.

TUBE SIZE (inch)

Nominal

K & L

1/4

3/8

1/2

5/8

3/4

1

11/4

11/2

2

ACR

3/8

1/2

5/8

3/4

7/8

11/8

13/8

Outside

0.375

0.500

0.625

0.750

0.875

1.125

1.375

1.625

2.125

Inside

0.305

0.402

0.527

0.652

0.745

0.995

1.245

1.481

1.959

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

303

625

1,270

2,220

3,150

6,740

12,100

19,100

39,800

20

208

430

874

1,530

2,170

4,630

8,330

13,100

27,400

30

167

345

702

1,230

1,740

3,720

6,690

10,600

22,000

40

143

295

601

1,050

1,490

3,180

5,730

9,030

18,800

50

127

262

532

931

1,320

2,820

5,080

8,000

16,700

60

115

237

482

843

1,200

2,560

4,600

7,250

15,100

70

106

218

444

776

1,100

2,350

4,230

6,670

13,900

80

98

203

413

722

1,020

2,190

3,940

6,210

12,900

90

92

190

387

677

961

2,050

3,690

5,820

12,100

100

87

180

366

640

907

1,940

3,490

5,500

11,500

125

77

159

324

567

804

1,720

3,090

4,880

10,200

150

70

144

294

514

729

1,560

2,800

4,420

9,200

175

64

133

270

472

670

1,430

2,580

4,060

8,460

200

60

124

252

440

624

1,330

2,400

3,780

7,870

250

53

110

223

390

553

1,180

2,130

3,350

6,980

300

48

99

202

353

501

1,070

1,930

3,040

6,320

350

44

91

186

325

461

984

1,770

2,790

5,820

400

41

85

173

302

429

916

1,650

2,600

5,410

450

39

80

162

283

402

859

1,550

2,440

5,080

500

36

75

153

268

380

811

1,460

2,300

4,800

550

35

72

146

254

361

771

1,390

2,190

4,560

600

33

68

139

243

344

735

1,320

2,090

4,350

650

32

65

133

232

330

704

1,270

2,000

4,160

700

30

63

128

223

317

676

1,220

1,920

4,000

750

29

60

123

215

305

652

1,170

1,850

3,850

800

28

58

119

208

295

629

1,130

1,790

3,720

850

27

57

115

201

285

609

1,100

1,730

3,600

900

27

55

111

195

276

590

1,060

1,680

3,490

950

26

53

108

189

268

573

1,030

1,630

3,390

1,000

25

52

105

184

261

558

1,000

1,580

3,300

1,100

24

49

100

175

248

530

954

1,500

3,130

1,200

23

47

95

167

237

505

910

1,430

2,990

1,300

22

45

91

160

227

484

871

1,370

2,860

1,400

21

43

88

153

218

465

837

1,320

2,750

1,500

20

42

85

148

210

448

806

1,270

2,650

1,600

19

40

82

143

202

432

779

1,230

2,560

1,700

19

39

79

138

196

419

753

1,190

2,470

1,800

18

38

77

134

190

406

731

1,150

2,400

1,900

18

37

74

130

184

394

709

1,120

2,330

2,000

17

36

72

126

179

383

690

1,090

2,270

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

2. Where this table is used to size the tubing upstream of a line pressure regulator, the pipe or tubing downstream of the line pressure regulator shall be sized using a pressure drop not greater than 1 inch w.c.

3. All table entries have been rounded to three significant digits.

TABLE 402.4(12)
SEMIRIGID COPPER TUBING

Gas

Natural

Inlet Pressure

5.0 psi

Pressure Drop

3.5 psi

Specific Gravity

0.60

TUBE SIZE (inch)

Nominal

K & L

1/4

3/8

1/2

5/8

3/4

1

11/4

11/2

2

ACR

3/8

1/2

5/8

3/4

7/8

11/8

13/8

Outside

0.375

0.500

0.625

0.750

0.875

1.125

1.375

1.625

2.125

Inside

0.305

0.402

0.527

0.652

0.745

0.995

1.245

1.481

1.959

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

511

1,050

2,140

3,750

5,320

11,400

20,400

32,200

67,100

20

351

724

1,470

2,580

3,650

7,800

14,000

22,200

46,100

30

282

582

1,180

2,070

2,930

6,270

11,300

17,800

37,000

40

241

498

1,010

1,770

2,510

5,360

9,660

15,200

31,700

50

214

441

898

1,570

2,230

4,750

8,560

13,500

28,100

60

194

400

813

1,420

2,020

4,310

7,750

12,200

25,500

70

178

368

748

1,310

1,860

3,960

7,130

11,200

23,400

80

166

342

696

1,220

1,730

3,690

6,640

10,500

21,800

90

156

321

653

1,140

1,620

3,460

6,230

9,820

20,400

100

147

303

617

1,080

1,530

3,270

5,880

9,270

19,300

125

130

269

547

955

1,360

2,900

5,210

8,220

17,100

150

118

243

495

866

1,230

2,620

4,720

7,450

15,500

175

109

224

456

796

1,130

2,410

4,350

6,850

14,300

200

101

208

424

741

1,050

2,250

4,040

6,370

13,300

250

90

185

376

657

932

1,990

3,580

5,650

11,800

300

81

167

340

595

844

1,800

3,250

5,120

10,700

350

75

154

313

547

777

1,660

2,990

4,710

9,810

400

69

143

291

509

722

1,540

2,780

4,380

9,120

450

65

134

273

478

678

1,450

2,610

4,110

8,560

500

62

127

258

451

640

1,370

2,460

3,880

8,090

550

58

121

245

429

608

1,300

2,340

3,690

7,680

600

56

115

234

409

580

1,240

2,230

3,520

7,330

650

53

110

224

392

556

1,190

2,140

3,370

7,020

700

51

106

215

376

534

1,140

2,050

3,240

6,740

750

49

102

207

362

514

1,100

1,980

3,120

6,490

800

48

98

200

350

497

1,060

1,910

3,010

6,270

850

46

95

194

339

481

1,030

1,850

2,910

6,070

900

45

92

188

328

466

1,000

1,790

2,820

5,880

950

43

90

182

319

452

967

1,740

2,740

5,710

1,000

42

87

177

310

440

940

1,690

2,670

5,560

1,100

40

83

169

295

418

893

1,610

2,530

5,280

1,200

38

79

161

281

399

852

1,530

2,420

5,040

1,300

37

76

154

269

382

816

1,470

2,320

4,820

1,400

35

73

148

259

367

784

1,410

2,220

4,630

1,500

34

70

143

249

353

755

1,360

2,140

4,460

1,600

33

68

138

241

341

729

1,310

2,070

4,310

1,700

32

65

133

233

330

705

1,270

2,000

4,170

1,800

31

63

129

226

320

684

1,230

1,940

4,040

1,900

30

62

125

219

311

664

1,200

1,890

3,930

2,000

29

60

122

213

302

646

1,160

1,830

3,820

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

2. All table entries have been rounded to three significant digits.

TABLE 402.4(13)
CORRUGATED STAINLESS STEEL TUBING (CSST)

Gas

Natural

Inlet Pressure

Less than 2 psi

Pressure Drop

0.5 in. w.c.

Specific Gravity

0.60

TUBE SIZE (EHD)

Flow
Designation

13

15

18

19

23

25

30

31

37

39

46

48

60

62

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

5

46

63

115

134

225

270

471

546

895

1,037

1,790

2,070

3,660

4,140

10

32

44

82

95

161

192

330

383

639

746

1,260

1,470

2,600

2,930

15

25

35

66

77

132

157

267

310

524

615

1,030

1,200

2,140

2,400

20

22

31

58

67

116

137

231

269

456

536

888

1,050

1,850

2,080

25

19

27

52

60

104

122

206

240

409

482

793

936

1,660

1,860

30

18

25

47

55

96

112

188

218

374

442

723

856

1,520

1,700

40

15

21

41

47

83

97

162

188

325

386

625

742

1,320

1,470

50

13

19

37

42

75

87

144

168

292

347

559

665

1,180

1,320

60

12

17

34

38

68

80

131

153

267

318

509

608

1,080

1,200

70

11

16

31

36

63

74

121

141

248

295

471

563

1,000

1,110

80

10

15

29

33

60

69

113

132

232

277

440

527

940

1,040

90

10

14

28

32

57

65

107

125

219

262

415

498

887

983

100

9

13

26

30

54

62

101

118

208

249

393

472

843

933

150

7

10

20

23

42

48

78

91

171

205

320

387

691

762

200

6

9

18

21

38

44

71

82

148

179

277

336

600

661

250

5

8

16

19

34

39

63

74

133

161

247

301

538

591

300

5

7

15

17

32

36

57

67

95

148

226

275

492

540

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends and/or fittings shall be increased by an equivalent length of tubing to the following equation: L = 1.3n, where L is additional length (feet) of tubing and n is the number of additional fittings and/or bends.

2. EHD—Equivalent Hydraulic Diameter, which is a measure of the relative hydraulic efficiency between different tubing sizes. The greater the value of EHD, the greater the gas capacity of the tubing.

3. All table entries have been rounded to three significant digits.

TABLE 402.4(14)
CORRUGATED STAINLESS STEEL TUBING (CSST)

Gas

Natural

Inlet Pressure

Less than 2 psi

Pressure Drop

3.0 in. w.c.

Specific Gravity

0.60

TUBE SIZE (EHD)

Flow
Designation

13

15

18

19

23

25

30

31

37

46

48

60

62

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

5

120

160

277

327

529

649

1,180

1,370

2,140

4,430

5,010

8,800

10,100

10

83

112

197

231

380

462

828

958

1,530

3,200

3,560

6,270

7,160

15

67

90

161

189

313

379

673

778

1,250

2,540

2,910

5,140

5,850

20

57

78

140

164

273

329

580

672

1,090

2,200

2,530

4,460

5,070

25

51

69

125

147

245

295

518

599

978

1,960

2,270

4,000

4,540

30

46

63

115

134

225

270

471

546

895

1,790

2,070

3,660

4,140

40

39

54

100

116

196

234

407

471

778

1,550

1,800

3,180

3,590

50

35

48

89

104

176

210

363

421

698

1,380

1,610

2,850

3,210

60

32

44

82

95

161

192

330

383

639

1,260

1,470

2,600

2,930

70

29

41

76

88

150

178

306

355

593

1,170

1,360

2,420

2,720

80

27

38

71

82

141

167

285

331

555

1,090

1,280

2,260

2,540

90

26

36

67

77

133

157

268

311

524

1,030

1,200

2,140

2,400

100

24

34

63

73

126

149

254

295

498

974

1,140

2,030

2,280

150

19

27

52

60

104

122

206

240

409

793

936

1,660

1,860

200

17

23

45

52

91

106

178

207

355

686

812

1,440

1,610

250

15

21

40

46

82

95

159

184

319

613

728

1,290

1,440

300

13

19

37

42

75

87

144

168

234

559

665

1,180

1,320

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends and/or fittings shall be increased by an equivalent length of tubing to the following equation: L = 1.3n where L is additional length (feet) of tubing and n is the number of additional fittings and/or bends.

2. EHD—Equivalent Hydraulic Diameter, which is a measure of the relative hydraulic efficiency between different tubing sizes. The greater the value of EHD, the greater the gas capacity of the tubing.

3. All table entries have been rounded to three significant digits.

TABLE 402.4(15)
CORRUGATED STAINLESS STEEL TUBING (CSST)

Gas

Natural

Inlet Pressure

Less than 2 psi

Pressure Drop

6.0 in. w.c.

Specific Gravity

0.60

TUBE SIZE (EHD)

Flow
Designation

13

15

18

19

23

25

30

31

37

46

48

60

62

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

5

173

229

389

461

737

911

1,690

1,950

3,000

6,280

7,050

12,400

14,260

10

120

160

277

327

529

649

1,180

1,370

2,140

4,430

5,010

8,800

10,100

15

96

130

227

267

436

532

960

1,110

1,760

3,610

4,100

7,210

8,260

20

83

112

197

231

380

462

828

958

1,530

3,120

3,560

6,270

7,160

25

74

99

176

207

342

414

739

855

1,370

2,790

3,190

5,620

6,400

30

67

90

161

189

313

379

673

778

1,250

2,540

2,910

5,140

5,850

40

57

78

140

164

273

329

580

672

1,090

2,200

2,530

4,460

5,070

50

51

69

125

147

245

295

518

599

978

1,960

2,270

4,000

4,540

60

46

63

115

134

225

270

471

546

895

1,790

2,070

3,660

4,140

70

42

58

106

124

209

250

435

505

830

1,660

1,920

3,390

3,840

80

39

54

100

116

196

234

407

471

778

1,550

1,800

3,180

3,590

90

37

51

94

109

185

221

383

444

735

1,460

1,700

3,000

3,390

100

35

48

89

104

176

210

363

421

698

1,380

1,610

2,850

3,210

150

28

39

73

85

145

172

294

342

573

1,130

1,320

2,340

2,630

200

24

34

63

73

126

149

254

295

498

974

1,140

2,030

2,280

250

21

30

57

66

114

134

226

263

447

870

1,020

1,820

2,040

300

19

27

52

60

104

122

206

240

409

793

936

1,660

1,860

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends and/or fittings shall be increased by an equivalent length of tubing to the following equation: L = 1.3n where L is additional length (feet) of tubing and n is the number of additional fittings and/or bends.

2. EHD—Equivalent Hydraulic Diameter, which is a measure of the relative hydraulic efficiency between different tubing sizes. The greater the value of EHD, the greater the gas capacity of the tubing.

3. All table entries have been rounded to three significant digits.

TABLE 402.4(16)
CORRUGATED STAINLESS STEEL TUBING (CSST)

Gas

Natural

Inlet Pressure

2.0 psi

Pressure Drop

1.0 psi

Specific Gravity

0.60

TUBE SIZE (EHD)

Flow
Designation

13

15

18

19

23

25

30

31

37

39

46

48

60

62

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

270

353

587

700

1,100

1,370

2,590

2,990

4,510

5,037

9,600

10,700

18,600

21,600

25

166

220

374

444

709

876

1,620

1,870

2,890

3,258

6,040

6,780

11,900

13,700

30

151

200

342

405

650

801

1,480

1,700

2,640

2,987

5,510

6,200

10,900

12,500

40

129

172

297

351

567

696

1,270

1,470

2,300

2,605

4,760

5,380

9,440

10,900

50

115

154

266

314

510

624

1,140

1,310

2,060

2,343

4,260

4,820

8,470

9,720

75

93

124

218

257

420

512

922

1,070

1,690

1,932

3,470

3,950

6,940

7,940

80

89

120

211

249

407

496

892

1,030

1,640

1,874

3,360

3,820

6,730

7,690

100

79

107

189

222

366

445

795

920

1,470

1,685

3,000

3,420

6,030

6,880

150

64

87

155

182

302

364

646

748

1,210

1,389

2,440

2,800

4,940

5,620

200

55

75

135

157

263

317

557

645

1,050

1,212

2,110

2,430

4,290

4,870

250

49

67

121

141

236

284

497

576

941

1,090

1,890

2,180

3,850

4,360

300

44

61

110

129

217

260

453

525

862

999

1,720

1,990

3,520

3,980

400

38

52

96

111

189

225

390

453

749

871

1,490

1,730

3,060

3,450

500

34

46

86

100

170

202

348

404

552

783

1,330

1,550

2,740

3,090

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table does not include effect of pressure drop across the line regulator. Where regulator loss exceeds 3/4 psi, DO NOT USE THIS TABLE. Consult with the regulator manufacturer for pressure drops and capacity factors. Pressure drops across a regulator may vary with flow rate.

2. CAUTION: Capacities shown in the table might exceed maximum capacity for a selected regulator. Consult with the regulator or tubing manufacturer for guidance.

3. Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends and/or fittings shall be increased by an equivalent length of tubing to the following equation: L = 1.3n where L is additional length (feet) of tubing and n is the number of additional fittings and/or bends.

4. EHD—Equivalent Hydraulic Diameter, which is a measure of the relative hydraulic efficiency between different tubing sizes. The greater the value of EHD, the greater the gas capacity of the tubing.

5. All table entries have been rounded to three significant digits.

TABLE 402.4(17)
CORRUGATED STAINLESS STEEL TUBING (CSST)

Gas

Natural

Inlet Pressure

5.0 psi

Pressure Drop

3.5 psi

Specific Gravity

0.60

TUBE SIZE (EHD)

Flow
Designation

13

15

18

19

23

25

30

31

37

39

46

48

60

62

Length (ft)

Capacity in Cubic Feet of Gas Per Hour

10

523

674

1,080

1,300

2,000

2,530

4,920

5,660

8,300

9,140

18,100

19,800

34,400

40,400

25

322

420

691

827

1,290

1,620

3,080

3,540

5,310

5,911

11,400

12,600

22,000

25,600

30

292

382

632

755

1,180

1,480

2,800

3,230

4,860

5,420

10,400

11,500

20,100

23,400

40

251

329

549

654

1,030

1,280

2,420

2,790

4,230

4,727

8,970

10,000

17,400

20,200

50

223

293

492

586

926

1,150

2,160

2,490

3,790

4,251

8,020

8,930

15,600

18,100

75

180

238

403

479

763

944

1,750

2,020

3,110

3,506

6,530

7,320

12,800

14,800

80

174

230

391

463

740

915

1,690

1,960

3,020

3,400

6,320

7,090

12,400

14,300

100

154

205

350

415

665

820

1,510

1,740

2,710

3,057

5,650

6,350

11,100

12,800

150

124

166

287

339

548

672

1,230

1,420

2,220

2,521

4,600

5,200

9,130

10,500

200

107

143

249

294

478

584

1,060

1,220

1,930

2,199

3,980

4,510

7,930

9,090

250

95

128

223

263

430

524

945

1,090

1,730

1,977

3,550

4,040

7,110

8,140

300

86

116

204

240

394

479

860

995

1,590

1,813

3,240

3,690

6,500

7,430

400

74

100

177

208

343

416

742

858

1,380

1,581

2,800

3,210

5,650

6,440

500

66

89

159

186

309

373

662

766

1,040

1,422

2,500

2,870

5,060

5,760

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table does not include effect of pressure drop across the line regulator. Where regulator loss exceeds 3/4 psi, DO NOT USE THIS TABLE. Consult with the regulator manufacturer for pressure drops and capacity factors. Pressure drops across a regulator may vary with flow rate.

2. CAUTION: Capacities shown in the table might exceed maximum capacity for a selected regulator. Consult with the regulator or tubing manufacturer for guidance.

3. Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends and/or fittings shall be increased by an equivalent length of tubing to the following equation: L = 1.3n where L is additional length (feet) of tubing and n is the number of additional fittings and/or bends.

4. EHD—Equivalent Hydraulic Diameter, which is a measure of the relative hydraulic efficiency between different tubing sizes. The greater the value of EHD, the greater the gas capacity of the tubing.

5. All table entries have been rounded to three significant digits.

TABLE 402.4(18)
POLYETHYLENE PLASTIC PIPE

Gas

Natural

Inlet Pressure

Less than 2 psi

Pressure Drop

0.3 in. w.c.

Specific Gravity

0.60

PIPE SIZE (inch)

Nominal OD

1/2

3/4

1

11/4

11/2

2

Designation

SDR 9.33

SDR 11.0

SDR 11.00

SDR 10.00

SDR 11.00

SDR 11.00

Actual ID

0.660

0.860

1.077

1.328

1.554

1.943

Length (ft)

Capacity in Cubic Feet of Gas per Hour

10

153

305

551

955

1,440

2,590

20

105

210

379

656

991

1,780

30

84

169

304

527

796

1,430

40

72

144

260

451

681

1,220

50

64

128

231

400

604

1,080

60

58

116

209

362

547

983

70

53

107

192

333

503

904

80

50

99

179

310

468

841

90

46

93

168

291

439

789

100

44

88

159

275

415

745

125

39

78

141

243

368

661

150

35

71

127

221

333

598

175

32

65

117

203

306

551

200

30

60

109

189

285

512

250

27

54

97

167

253

454

300

24

48

88

152

229

411

350

22

45

81

139

211

378

400

21

42

75

130

196

352

450

19

39

70

122

184

330

500

18

37

66

115

174

312

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(19)
POLYETHYLENE PLASTIC PIPE

Gas

Natural

Inlet Pressure

Less than 2 psi

Pressure Drop

0.5 in. w.c.

Specific Gravity

0.60

PIPE SIZE (inch)

Nominal OD

1/2

3/4

1

11/4

11/2

2

Designation

SDR 9.33

SDR 11.0

SDR 11.00

SDR 10.00

SDR 11.00

SDR 11.00

Actual ID

0.660

0.860

1.077

1.328

1.554

1.943

Length (ft)

Capacity in Cubic Feet of Gas per Hour

10

201

403

726

1,260

1,900

3,410

20

138

277

499

865

1,310

2,350

30

111

222

401

695

1,050

1,880

40

95

190

343

594

898

1,610

50

84

169

304

527

796

1,430

60

76

153

276

477

721

1,300

70

70

140

254

439

663

1,190

80

65

131

236

409

617

1,110

90

61

123

221

383

579

1,040

100

58

116

209

362

547

983

125

51

103

185

321

485

871

150

46

93

168

291

439

789

175

43

86

154

268

404

726

200

40

80

144

249

376

675

250

35

71

127

221

333

598

300

32

64

115

200

302

542

350

29

59

106

184

278

499

400

27

55

99

171

258

464

450

26

51

93

160

242

435

500

24

48

88

152

229

411

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(20)
POLYETHYLENE PLASTIC PIPE

Gas

Natural

Inlet Pressure

2.0 psi

Pressure Drop

1.0 psi

Specific Gravity

0.60

PIPE SIZE (inch)

Nominal OD

1/2

3/4

1

11/4

11/2

2

Designation

SDR 9.33

SDR 11.0

SDR 11.00

SDR 10.00

SDR 11.00

SDR 11.00

Actual ID

0.660

0.860

1.077

1.328

1.554

1.943

Length (ft)

Capacity in Cubic Feet of Gas per Hour

10

1,860

3,720

6,710

11,600

17,600

31,600

20

1,280

2,560

4,610

7,990

12,100

21,700

30

1,030

2,050

3,710

6,420

9,690

17,400

40

878

1,760

3,170

5,490

8,300

14,900

50

778

1,560

2,810

4,870

7,350

13,200

60

705

1,410

2,550

4,410

6,660

12,000

70

649

1,300

2,340

4,060

6,130

11,000

80

603

1,210

2,180

3,780

5,700

10,200

90

566

1,130

2,050

3,540

5,350

9,610

100

535

1,070

1,930

3,350

5,050

9,080

125

474

949

1,710

2,970

4,480

8,050

150

429

860

1,550

2,690

4,060

7,290

175

395

791

1,430

2,470

3,730

6,710

200

368

736

1,330

2,300

3,470

6,240

250

326

652

1,180

2,040

3,080

5,530

300

295

591

1,070

1,850

2,790

5,010

350

272

544

981

1,700

2,570

4,610

400

253

506

913

1,580

2,390

4,290

450

237

475

856

1,480

2,240

4,020

500

224

448

809

1,400

2,120

3,800

550

213

426

768

1,330

2,010

3,610

600

203

406

733

1,270

1,920

3,440

650

194

389

702

1,220

1,840

3,300

700

187

374

674

1,170

1,760

3,170

750

180

360

649

1,130

1,700

3,050

800

174

348

627

1,090

1,640

2,950

850

168

336

607

1,050

1,590

2,850

900

163

326

588

1,020

1,540

2,770

950

158

317

572

990

1,500

2,690

1,000

154

308

556

963

1,450

2,610

1,100

146

293

528

915

1,380

2,480

1,200

139

279

504

873

1,320

2,370

1,300

134

267

482

836

1,260

2,270

1,400

128

257

463

803

1,210

2,180

1,500

124

247

446

773

1,170

2,100

1,600

119

239

431

747

1,130

2,030

1,700

115

231

417

723

1,090

1,960

1,800

112

224

404

701

1,060

1,900

1,900

109

218

393

680

1,030

1,850

2,000

106

212

382

662

1,000

1,800

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(21)
POLYETHYLENE PLASTIC TUBING

Gas

Natural

Inlet Pressure

Less than 2.0 psi

Pressure Drop

0.3 in. w.c.

Specific Gravity

0.60

PLASTIC TUBING SIZE (CTS) (inch)

Nominal OD

1/2

3/4

Designation

SDR 7.00

SDR 11.00

Actual ID

0.445

0.927

Length (ft)

Capacity in Cubic Feet of Gas per Hour

10

54

372

20

37

256

30

30

205

40

26

176

50

23

156

60

21

141

70

19

130

80

18

121

90

17

113

100

16

107

125

14

95

150

13

86

175

12

79

200

11

74

225

10

69

250

NA

65

275

NA

62

300

NA

59

350

NA

54

400

NA

51

450

NA

47

500

NA

45

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm,
1 pound per square inch = 6.895 kPa,
1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W,
1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. NA means a flow of less than 10 cfh.

2. All table entries have been rounded to three significant digits.

TABLE 402.4(22)
POLYETHYLENE PLASTIC TUBING

Gas

Natural

Inlet Pressure

Less than 2.0 psi

Pressure Drop

0.5 in. w.c.

Specific Gravity

0.60

PLASTIC TUBING SIZE (CTS) (inch)

Nominal OD

1/2

3/4

Designation

SDR 7.00

SDR 11.00

Actual ID

0.445

0.927

Length (ft)

Capacity in Cubic Feet of Gas per Hour

10

72

490

20

49

337

30

39

271

40

34

232

50

30

205

60

27

186

70

25

171

80

23

159

90

22

149

100

21

141

125

18

125

150

17

113

175

15

104

200

14

97

225

13

91

250

12

86

275

11

82

300

11

78

350

10

72

400

NA

67

450

NA

63

500

NA

59

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm,
1 pound per square inch = 6.895 kPa,
1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W,
1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. NA means a flow of less than 10 cfh.

2. All table entries have been rounded to three significant digits.

TABLE 402.4(23)
SCHEDULE 40 METALLIC PIPE

Gas

Undiluted Propane

Inlet Pressure

10.0 psi

Pressure Drop

1.0 psi

Specific Gravity

1.50

INTENDED USE

Pipe sizing between first stage (high-pressure regulator) and second stage (low-pressure regulator).

PIPE SIZE (inch)

Nominal

1/2

3/4

1

11/4

11/2

2

21/2

3

4

Actual ID

0.622

0.824

1.049

1.380

1.610

2.067

2.469

3.068

4.026

Length (ft)

Capacity in Thousands of Btu per Hour

10

3,320

6,950

13,100

26,900

40,300

77,600

124,000

219,000

446,000

20

2,280

4,780

9,000

18,500

27,700

53,300

85,000

150,000

306,000

30

1,830

3,840

7,220

14,800

22,200

42,800

68,200

121,000

246,000

40

1,570

3,280

6,180

12,700

19,000

36,600

58,400

103,000

211,000

50

1,390

2,910

5,480

11,300

16,900

32,500

51,700

91,500

187,000

60

1,260

2,640

4,970

10,200

15,300

29,400

46,900

82,900

169,000

70

1,160

2,430

4,570

9,380

14,100

27,100

43,100

76,300

156,000

80

1,080

2,260

4,250

8,730

13,100

25,200

40,100

70,900

145,000

90

1,010

2,120

3,990

8,190

12,300

23,600

37,700

66,600

136,000

100

956

2,000

3,770

7,730

11,600

22,300

35,600

62,900

128,000

125

848

1,770

3,340

6,850

10,300

19,800

31,500

55,700

114,000

150

768

1,610

3,020

6,210

9,300

17,900

28,600

50,500

103,000

175

706

1,480

2,780

5,710

8,560

16,500

26,300

46,500

94,700

200

657

1,370

2,590

5,320

7,960

15,300

24,400

43,200

88,100

250

582

1,220

2,290

4,710

7,060

13,600

21,700

38,300

78,100

300

528

1,100

2,080

4,270

6,400

12,300

19,600

34,700

70,800

350

486

1,020

1,910

3,930

5,880

11,300

18,100

31,900

65,100

400

452

945

1,780

3,650

5,470

10,500

16,800

29,700

60,600

450

424

886

1,670

3,430

5,140

9,890

15,800

27,900

56,800

500

400

837

1,580

3,240

4,850

9,340

14,900

26,300

53,700

550

380

795

1,500

3,070

4,610

8,870

14,100

25,000

51,000

600

363

759

1,430

2,930

4,400

8,460

13,500

23,900

48,600

650

347

726

1,370

2,810

4,210

8,110

12,900

22,800

46,600

700

334

698

1,310

2,700

4,040

7,790

12,400

21,900

44,800

750

321

672

1,270

2,600

3,900

7,500

12,000

21,100

43,100

800

310

649

1,220

2,510

3,760

7,240

11,500

20,400

41,600

850

300

628

1,180

2,430

3,640

7,010

11,200

19,800

40,300

900

291

609

1,150

2,360

3,530

6,800

10,800

19,200

39,100

950

283

592

1,110

2,290

3,430

6,600

10,500

18,600

37,900

1,000

275

575

1,080

2,230

3,330

6,420

10,200

18,100

36,900

1,100

261

546

1,030

2,110

3,170

6,100

9,720

17,200

35,000

1,200

249

521

982

2,020

3,020

5,820

9,270

16,400

33,400

1,300

239

499

940

1,930

2,890

5,570

8,880

15,700

32,000

1,400

229

480

903

1,850

2,780

5,350

8,530

15,100

30,800

1,500

221

462

870

1,790

2,680

5,160

8,220

14,500

29,600

1,600

213

446

840

1,730

2,590

4,980

7,940

14,000

28,600

1,700

206

432

813

1,670

2,500

4,820

7,680

13,600

27,700

1,800

200

419

789

1,620

2,430

4,670

7,450

13,200

26,900

1,900

194

407

766

1,570

2,360

4,540

7,230

12,800

26,100

2,000

189

395

745

1,530

2,290

4,410

7,030

12,400

25,400

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(24)
SCHEDULE 40 METALLIC PIPE

Gas

Undiluted Propane

Inlet Pressure

10.0 psi

Pressure Drop

3.0 psi

Specific Gravity

1.50

INTENDED USE

Pipe sizing between first stage (high-pressure regulator) and second stage (low-pressure regulator).

PIPE SIZE (inch)

Nominal

1/2

3/4

1

11/4

11/2

2

21/2

3

4

Actual ID

0.622

0.824

1.049

1.380

1.610

2.067

2.469

3.068

4.026

Length (ft)

Capacity in Thousands of Btu per Hour

10

5,890

12,300

23,200

47,600

71,300

137,000

219,000

387,000

789,000

20

4,050

8,460

15,900

32,700

49,000

94,400

150,000

266,000

543,000

30

3,250

6,790

12,800

26,300

39,400

75,800

121,000

214,000

436,000

40

2,780

5,810

11,000

22,500

33,700

64,900

103,000

183,000

373,000

50

2,460

5,150

9,710

19,900

29,900

57,500

91,600

162,000

330,000

60

2,230

4,670

8,790

18,100

27,100

52,100

83,000

147,000

299,000

70

2,050

4,300

8,090

16,600

24,900

47,900

76,400

135,000

275,000

80

1,910

4,000

7,530

15,500

23,200

44,600

71,100

126,000

256,000

90

1,790

3,750

7,060

14,500

21,700

41,800

66,700

118,000

240,000

100

1,690

3,540

6,670

13,700

20,500

39,500

63,000

111,000

227,000

125

1,500

3,140

5,910

12,100

18,200

35,000

55,800

98,700

201,000

150

1,360

2,840

5,360

11,000

16,500

31,700

50,600

89,400

182,000

175

1,250

2,620

4,930

10,100

15,200

29,200

46,500

82,300

167,800

200

1,160

2,430

4,580

9,410

14,100

27,200

43,300

76,500

156,100

250

1,030

2,160

4,060

8,340

12,500

24,100

38,400

67,800

138,400

300

935

1,950

3,680

7,560

11,300

21,800

34,800

61,500

125,400

350

860

1,800

3,390

6,950

10,400

20,100

32,000

56,500

115,300

400

800

1,670

3,150

6,470

9,690

18,700

29,800

52,600

107,300

450

751

1,570

2,960

6,070

9,090

17,500

27,900

49,400

100,700

500

709

1,480

2,790

5,730

8,590

16,500

26,400

46,600

95,100

550

673

1,410

2,650

5,450

8,160

15,700

25,000

44,300

90,300

600

642

1,340

2,530

5,200

7,780

15,000

23,900

42,200

86,200

650

615

1,290

2,420

4,980

7,450

14,400

22,900

40,500

82,500

700

591

1,240

2,330

4,780

7,160

13,800

22,000

38,900

79,300

750

569

1,190

2,240

4,600

6,900

13,300

21,200

37,400

76,400

800

550

1,150

2,170

4,450

6,660

12,800

20,500

36,200

73,700

850

532

1,110

2,100

4,300

6,450

12,400

19,800

35,000

71,400

900

516

1,080

2,030

4,170

6,250

12,000

19,200

33,900

69,200

950

501

1,050

1,970

4,050

6,070

11,700

18,600

32,900

67,200

1,000

487

1,020

1,920

3,940

5,900

11,400

18,100

32,000

65,400

1,100

463

968

1,820

3,740

5,610

10,800

17,200

30,400

62,100

1,200

442

923

1,740

3,570

5,350

10,300

16,400

29,000

59,200

1,300

423

884

1,670

3,420

5,120

9,870

15,700

27,800

56,700

1,400

406

849

1,600

3,280

4,920

9,480

15,100

26,700

54,500

1,500

391

818

1,540

3,160

4,740

9,130

14,600

25,700

52,500

1,600

378

790

1,490

3,060

4,580

8,820

14,100

24,800

50,700

1,700

366

765

1,440

2,960

4,430

8,530

13,600

24,000

49,000

1,800

355

741

1,400

2,870

4,300

8,270

13,200

23,300

47,600

1,900

344

720

1,360

2,780

4,170

8,040

12,800

22,600

46,200

2,000

335

700

1,320

2,710

4,060

7,820

12,500

22,000

44,900

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(25)
SCHEDULE 40 METALLIC PIPE

Gas

Undiluted Propane

Inlet Pressure

2.0 psi

Pressure Drop

1.0 psi

Specific Gravity

1.50

INTENDED USE

Pipe sizing between 2 psig service and line pressure regulator.

PIPE SIZE (inch)

Nominal

1/2

3/4

1

11/4

11/2

2

21/2

3

4

Actual ID

0.622

0.824

1.049

1.380

1.610

2.067

2.469

3.068

4.026

Length (ft)

Capacity in Thousands of Btu per Hour

10

2,680

5,590

10,500

21,600

32,400

62,400

99,500

176,000

359,000

20

1,840

3,850

7,240

14,900

22,300

42,900

68,400

121,000

247,000

30

1,480

3,090

5,820

11,900

17,900

34,500

54,900

97,100

198,000

40

1,260

2,640

4,980

10,200

15,300

29,500

47,000

83,100

170,000

50

1,120

2,340

4,410

9,060

13,600

26,100

41,700

73,700

150,000

60

1,010

2,120

4,000

8,210

12,300

23,700

37,700

66,700

136,000

70

934

1,950

3,680

7,550

11,300

21,800

34,700

61,400

125,000

80

869

1,820

3,420

7,020

10,500

20,300

32,300

57,100

116,000

90

815

1,700

3,210

6,590

9,880

19,000

30,300

53,600

109,000

100

770

1,610

3,030

6,230

9,330

18,000

28,600

50,600

103,000

125

682

1,430

2,690

5,520

8,270

15,900

25,400

44,900

91,500

150

618

1,290

2,440

5,000

7,490

14,400

23,000

40,700

82,900

175

569

1,190

2,240

4,600

6,890

13,300

21,200

37,400

76,300

200

529

1,110

2,080

4,280

6,410

12,300

19,700

34,800

71,000

250

469

981

1,850

3,790

5,680

10,900

17,400

30,800

62,900

300

425

889

1,670

3,440

5,150

9,920

15,800

27,900

57,000

350

391

817

1,540

3,160

4,740

9,120

14,500

25,700

52,400

400

364

760

1,430

2,940

4,410

8,490

13,500

23,900

48,800

450

341

714

1,340

2,760

4,130

7,960

12,700

22,400

45,800

500

322

674

1,270

2,610

3,910

7,520

12,000

21,200

43,200

550

306

640

1,210

2,480

3,710

7,140

11,400

20,100

41,100

600

292

611

1,150

2,360

3,540

6,820

10,900

19,200

39,200

650

280

585

1,100

2,260

3,390

6,530

10,400

18,400

37,500

700

269

562

1,060

2,170

3,260

6,270

9,990

17,700

36,000

750

259

541

1,020

2,090

3,140

6,040

9,630

17,000

34,700

800

250

523

985

2,020

3,030

5,830

9,300

16,400

33,500

850

242

506

953

1,960

2,930

5,640

9,000

15,900

32,400

900

235

490

924

1,900

2,840

5,470

8,720

15,400

31,500

950

228

476

897

1,840

2,760

5,310

8,470

15,000

30,500

1,000

222

463

873

1,790

2,680

5,170

8,240

14,600

29,700

1,100

210

440

829

1,700

2,550

4,910

7,830

13,800

28,200

1,200

201

420

791

1,620

2,430

4,680

7,470

13,200

26,900

1,300

192

402

757

1,550

2,330

4,490

7,150

12,600

25,800

1,400

185

386

727

1,490

2,240

4,310

6,870

12,100

24,800

1,500

178

372

701

1,440

2,160

4,150

6,620

11,700

23,900

1,600

172

359

677

1,390

2,080

4,010

6,390

11,300

23,000

1,700

166

348

655

1,340

2,010

3,880

6,180

10,900

22,300

1,800

161

337

635

1,300

1,950

3,760

6,000

10,600

21,600

1,900

157

327

617

1,270

1,900

3,650

5,820

10,300

21,000

2,000

152

318

600

1,230

1,840

3,550

5,660

10,000

20,400

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(26)
SCHEDULE 40 METALLIC PIPE

Gas

Undiluted Propane

Inlet Pressure

11.0 in. w.c.

Pressure Drop

0.5 in. w.c.

Specific Gravity

1.50

INTENDED USE

Pipe sizing between single- or second-stage (low pressure) regulator and appliance.

PIPE SIZE (inch)

Nominal

1/2

3/4

1

11/4

11/2

2

21/2

3

4

Actual ID

0.622

0.824

1.049

1.380

1.610

2.067

2.469

3.068

4.026

Length (ft)

Capacity in Thousands of Btu per Hour

10

291

608

1,150

2,350

3,520

6,790

10,800

19,100

39,000

20

200

418

787

1,620

2,420

4,660

7,430

13,100

26,800

30

160

336

632

1,300

1,940

3,750

5,970

10,600

21,500

40

137

287

541

1,110

1,660

3,210

5,110

9,030

18,400

50

122

255

480

985

1,480

2,840

4,530

8,000

16,300

60

110

231

434

892

1,340

2,570

4,100

7,250

14,800

80

101

212

400

821

1,230

2,370

3,770

6,670

13,600

100

94

197

372

763

1,140

2,200

3,510

6,210

12,700

125

89

185

349

716

1,070

2,070

3,290

5,820

11,900

150

84

175

330

677

1,010

1,950

3,110

5,500

11,200

175

74

155

292

600

899

1,730

2,760

4,880

9,950

200

67

140

265

543

814

1,570

2,500

4,420

9,010

250

62

129

243

500

749

1,440

2,300

4,060

8,290

300

58

120

227

465

697

1,340

2,140

3,780

7,710

350

51

107

201

412

618

1,190

1,900

3,350

6,840

400

46

97

182

373

560

1,080

1,720

3,040

6,190

450

42

89

167

344

515

991

1,580

2,790

5,700

500

40

83

156

320

479

922

1,470

2,600

5,300

550

37

78

146

300

449

865

1,380

2,440

4,970

600

35

73

138

283

424

817

1,300

2,300

4,700

650

33

70

131

269

403

776

1,240

2,190

4,460

700

32

66

125

257

385

741

1,180

2,090

4,260

750

30

64

120

246

368

709

1,130

2,000

4,080

800

29

61

115

236

354

681

1,090

1,920

3,920

850

28

59

111

227

341

656

1,050

1,850

3,770

900

27

57

107

220

329

634

1,010

1,790

3,640

950

26

55

104

213

319

613

978

1,730

3,530

1,000

25

53

100

206

309

595

948

1,680

3,420

1,100

25

52

97

200

300

578

921

1,630

3,320

1,200

24

50

95

195

292

562

895

1,580

3,230

1,300

23

48

90

185

277

534

850

1,500

3,070

1,400

22

46

86

176

264

509

811

1,430

2,930

1,500

21

44

82

169

253

487

777

1,370

2,800

1,600

20

42

79

162

243

468

746

1,320

2,690

1,700

19

40

76

156

234

451

719

1,270

2,590

1,800

19

39

74

151

226

436

694

1,230

2,500

1,900

18

38

71

146

219

422

672

1,190

2,420

2,000

18

37

69

142

212

409

652

1,150

2,350

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(27)
SEMIRIGID COPPER TUBING

Gas

Undiluted Propane

Inlet Pressure

10.0 psi

Pressure Drop

1.0 psi

Specific Gravity

1.50

INTENDED USE

Sizing between first stage (high-pressure regulator) and second stage (low-pressure regulator).

TUBE SIZE (in.)

Nominal

K & L

1/4

3/8

1/2

5/8

3/4

1

11/4

11/2

2

ACR

3/8

1/2

5/8

3/4

7/8

11/8

13/8

Outside

0.375

0.500

0.625

0.750

0.875

1.125

1.375

1.625

2.125

Inside

0.305

0.402

0.527

0.652

0.745

0.995

1.245

1.481

1.959

Length (ft)

Capacity in Thousands of Btu per Hour

10

513

1,060

2,150

3,760

5,330

11,400

20,500

32,300

67,400

20

352

727

1,480

2,580

3,670

7,830

14,100

22,200

46,300

30

283

584

1,190

2,080

2,940

6,290

11,300

17,900

37,200

40

242

500

1,020

1,780

2,520

5,380

9,690

15,300

31,800

50

215

443

901

1,570

2,230

4,770

8,590

13,500

28,200

60

194

401

816

1,430

2,020

4,320

7,780

12,300

25,600

70

179

369

751

1,310

1,860

3,980

7,160

11,300

23,500

80

166

343

699

1,220

1,730

3,700

6,660

10,500

21,900

90

156

322

655

1,150

1,630

3,470

6,250

9,850

20,500

100

147

304

619

1,080

1,540

3,280

5,900

9,310

19,400

125

131

270

549

959

1,360

2,910

5,230

8,250

17,200

150

118

244

497

869

1,230

2,630

4,740

7,470

15,600

175

109

225

457

799

1,130

2,420

4,360

6,880

14,300

200

101

209

426

744

1,060

2,250

4,060

6,400

13,300

250

90

185

377

659

935

2,000

3,600

5,670

11,800

300

81

168

342

597

847

1,810

3,260

5,140

10,700

350

75

155

314

549

779

1,660

3,000

4,730

9,840

400

70

144

292

511

725

1,550

2,790

4,400

9,160

450

65

135

274

480

680

1,450

2,620

4,130

8,590

500

62

127

259

453

643

1,370

2,470

3,900

8,120

550

59

121

246

430

610

1,300

2,350

3,700

7,710

600

56

115

235

410

582

1,240

2,240

3,530

7,350

650

54

111

225

393

558

1,190

2,140

3,380

7,040

700

51

106

216

378

536

1,140

2,060

3,250

6,770

750

50

102

208

364

516

1,100

1,980

3,130

6,520

800

48

99

201

351

498

1,060

1,920

3,020

6,290

850

46

96

195

340

482

1,030

1,850

2,920

6,090

900

45

93

189

330

468

1,000

1,800

2,840

5,910

950

44

90

183

320

454

970

1,750

2,750

5,730

1,000

42

88

178

311

442

944

1,700

2,680

5,580

1,100

40

83

169

296

420

896

1,610

2,540

5,300

1,200

38

79

161

282

400

855

1,540

2,430

5,050

1,300

37

76

155

270

383

819

1,470

2,320

4,840

1,400

35

73

148

260

368

787

1,420

2,230

4,650

1,500

34

70

143

250

355

758

1,360

2,150

4,480

1,600

33

68

138

241

343

732

1,320

2,080

4,330

1,700

32

66

134

234

331

708

1,270

2,010

4,190

1,800

31

64

130

227

321

687

1,240

1,950

4,060

1,900

30

62

126

220

312

667

1,200

1,890

3,940

2,000

29

60

122

214

304

648

1,170

1,840

3,830

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

2. All table entries have been rounded to three significant digits.

TABLE 402.4(28)
SEMIRIGID COPPER TUBING

Gas

Undiluted Propane

Inlet Pressure

11.0 in. w.c.

Pressure Drop

0.5 in. w.c.

Specific Gravity

1.50

INTENDED USE

Sizing between single or second stage (low-pressure regulator) and appliance.

TUBE SIZE (inch)

Nominal

K & L

1/4

3/8

1/2

5/8

3/4

1

11/4

11/2

2

ACR

3/8

1/2

5/8

3/4

7/8

11/8

13/8

Outside

0.375

0.500

0.625

0.750

0.875

1.125

1.375

1.625

2.125

Inside

0.305

0.402

0.527

0.652

0.745

0.995

1.245

1.481

1.959

Length (ft)

Capacity in Thousands of Btu per Hour

10

45

93

188

329

467

997

1,800

2,830

5,890

20

31

64

129

226

321

685

1,230

1,950

4,050

30

25

51

104

182

258

550

991

1,560

3,250

40

21

44

89

155

220

471

848

1,340

2,780

50

19

39

79

138

195

417

752

1,180

2,470

60

17

35

71

125

177

378

681

1,070

2,240

70

16

32

66

115

163

348

626

988

2,060

80

15

30

61

107

152

324

583

919

1,910

90

14

28

57

100

142

304

547

862

1,800

100

13

27

54

95

134

287

517

814

1,700

125

11

24

48

84

119

254

458

722

1,500

150

10

21

44

76

108

230

415

654

1,360

175

NA

20

40

70

99

212

382

602

1,250

200

NA

18

37

65

92

197

355

560

1,170

250

NA

16

33

58

82

175

315

496

1,030

300

NA

15

30

52

74

158

285

449

936

350

NA

14

28

48

68

146

262

414

861

400

NA

13

26

45

63

136

244

385

801

450

NA

12

24

42

60

127

229

361

752

500

NA

11

23

40

56

120

216

341

710

550

NA

11

22

38

53

114

205

324

674

600

NA

10

21

36

51

109

196

309

643

650

NA

NA

20

34

49

104

188

296

616

700

NA

NA

19

33

47

100

180

284

592

750

NA

NA

18

32

45

96

174

274

570

800

NA

NA

18

31

44

93

168

264

551

850

NA

NA

17

30

42

90

162

256

533

900

NA

NA

17

29

41

87

157

248

517

950

NA

NA

16

28

40

85

153

241

502

1,000

NA

NA

16

27

39

83

149

234

488

1,100

NA

NA

15

26

37

78

141

223

464

1,200

NA

NA

14

25

35

75

135

212

442

1,300

NA

NA

14

24

34

72

129

203

423

1,400

NA

NA

13

23

32

69

124

195

407

1,500

NA

NA

13

22

31

66

119

188

392

1,600

NA

NA

12

21

30

64

115

182

378

1,700

NA

NA

12

20

29

62

112

176

366

1,800

NA

NA

11

20

28

60

108

170

355

1,900

NA

NA

11

19

27

58

105

166

345

2,000

NA

NA

11

19

27

57

102

161

335

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

2. NA means a flow of less than 10,000 Btu/hr.

3. All table entries have been rounded to three significant digits.

TABLE 402.4(29)
SEMIRIGID COPPER TUBING

Gas

Undiluted Propane

Inlet Pressure

2.0 psi

Pressure Drop

1.0 psi

Specific Gravity

1.50

INTENDED USE

Tube sizing between 2 psig service and line pressure regulator.

TUBE SIZE (inch)

Nominal

K & L

1/4

3/8

1/2

5/8

3/4

1

11/4

11/2

2

ACR

3/8

1/2

5/8

3/4

7/8

11/8

13/8

Outside

0.375

0.500

0.625

0.750

0.875

1.125

1.375

1.625

2.125

Inside

0.305

0.402

0.527

0.652

0.745

0.995

1.245

1.481

1.959

Length (ft)

Capacity in Thousands of Btu per Hour

10

413

852

1,730

3,030

4,300

9,170

16,500

26,000

54,200

20

284

585

1,190

2,080

2,950

6,310

11,400

17,900

37,300

30

228

470

956

1,670

2,370

5,060

9,120

14,400

29,900

40

195

402

818

1,430

2,030

4,330

7,800

12,300

25,600

50

173

356

725

1,270

1,800

3,840

6,920

10,900

22,700

60

157

323

657

1,150

1,630

3,480

6,270

9,880

20,600

70

144

297

605

1,060

1,500

3,200

5,760

9,090

18,900

80

134

276

562

983

1,390

2,980

5,360

8,450

17,600

90

126

259

528

922

1,310

2,790

5,030

7,930

16,500

100

119

245

498

871

1,240

2,640

4,750

7,490

15,600

125

105

217

442

772

1,100

2,340

4,210

6,640

13,800

150

95

197

400

700

992

2,120

3,820

6,020

12,500

175

88

181

368

644

913

1,950

3,510

5,540

11,500

200

82

168

343

599

849

1,810

3,270

5,150

10,700

250

72

149

304

531

753

1,610

2,900

4,560

9,510

300

66

135

275

481

682

1,460

2,620

4,140

8,610

350

60

124

253

442

628

1,340

2,410

3,800

7,920

400

56

116

235

411

584

1,250

2,250

3,540

7,370

450

53

109

221

386

548

1,170

2,110

3,320

6,920

500

50

103

209

365

517

1,110

1,990

3,140

6,530

550

47

97

198

346

491

1,050

1,890

2,980

6,210

600

45

93

189

330

469

1,000

1,800

2,840

5,920

650

43

89

181

316

449

959

1,730

2,720

5,670

700

41

86

174

304

431

921

1,660

2,620

5,450

750

40

82

168

293

415

888

1,600

2,520

5,250

800

39

80

162

283

401

857

1,540

2,430

5,070

850

37

77

157

274

388

829

1,490

2,350

4,900

900

36

75

152

265

376

804

1,450

2,280

4,750

950

35

72

147

258

366

781

1,410

2,220

4,620

1,000

34

71

143

251

356

760

1,370

2,160

4,490

1,100

32

67

136

238

338

721

1,300

2,050

4,270

1,200

31

64

130

227

322

688

1,240

1,950

4,070

1,300

30

61

124

217

309

659

1,190

1,870

3,900

1,400

28

59

120

209

296

633

1,140

1,800

3,740

1,500

27

57

115

201

286

610

1,100

1,730

3,610

1,600

26

55

111

194

276

589

1,060

1,670

3,480

1,700

26

53

108

188

267

570

1,030

1,620

3,370

1,800

25

51

104

182

259

553

1,000

1,570

3,270

1,900

24

50

101

177

251

537

966

1,520

3,170

2,000

23

48

99

172

244

522

940

1,480

3,090

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

2. All table entries have been rounded to three significant digits.

TABLE 402.4(30)
CORRUGATED STAINLESS STEEL TUBING (CSST)

Gas

Undiluted Propane

Inlet Pressure

11.0 in. w.c.

Pressure Drop

0.5 in. w.c.

Specific Gravity

1.50

INTENDED USE: SIZING BETWEEN SINGLE OR SECOND STAGE (Low Pressure) REGULATOR AND THE APPLIANCE SHUTOFF VALVE

TUBE SIZE (EHD)

Flow
Designation

13

15

18

19

23

25

30

31

37

39

46

48

60

62

Length (ft)

Capacity in Thousands of Btu per Hour

5

72

99

181

211

355

426

744

863

1,420

1,638

2,830

3,270

5,780

6,550

10

50

69

129

150

254

303

521

605

971

1,179

1,990

2,320

4,110

4,640

15

39

55

104

121

208

248

422

490

775

972

1,620

1,900

3,370

3,790

20

34

49

91

106

183

216

365

425

661

847

1,400

1,650

2,930

3,290

25

30

42

82

94

164

192

325

379

583

762

1,250

1,480

2,630

2,940

30

28

39

74

87

151

177

297

344

528

698

1,140

1,350

2,400

2,680

40

23

33

64

74

131

153

256

297

449

610

988

1,170

2,090

2,330

50

20

30

58

66

118

137

227

265

397

548

884

1,050

1,870

2,080

60

19

26

53

60

107

126

207

241

359

502

805

961

1,710

1,900

70

17

25

49

57

99

117

191

222

330

466

745

890

1,590

1,760

80

15

23

45

52

94

109

178

208

307

438

696

833

1,490

1,650

90

15

22

44

50

90

102

169

197

286

414

656

787

1,400

1,550

100

14

20

41

47

85

98

159

186

270

393

621

746

1,330

1,480

150

11

15

31

36

66

75

123

143

217

324

506

611

1,090

1,210

200

9

14

28

33

60

69

112

129

183

283

438

531

948

1,050

250

8

12

25

30

53

61

99

117

163

254

390

476

850

934

300

8

11

23

26

50

57

90

107

147

234

357

434

777

854

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends and/or fittings shall be increased by an equivalent length of tubing to the following equation: L = 1.3n where L is additional length (feet) of tubing and n is the number of additional fittings and/or bends.

2. EHD—Equivalent Hydraulic Diameter, which is a measure of the relative hydraulic efficiency between different tubing sizes. The greater the value of EHD, the greater the gas capacity of the tubing.

3. All table entries have been rounded to three significant digits.

TABLE 402.4(31)
CORRUGATED STAINLESS STEEL TUBING (CSST)

Gas

Undiluted Propane

Inlet Pressure

2.0 psi

Pressure Drop

1.0 psi

Specific Gravity

1.50

INTENDED USE: SIZING BETWEEN 2 PSI SERVICE AND THE LINE PRESSURE REGULATOR

TUBE SIZE (EHD)

Flow
Designation

13

15

18

19

23

25

30

31

37

39

46

48

60

62

Length (ft)

Capacity in Thousands of Btu per Hour

10

426

558

927

1,110

1,740

2,170

4,100

4,720

7,130

7,958

15,200

16,800

29,400

34,200

25

262

347

591

701

1,120

1,380

2,560

2,950

4,560

5,147

9,550

10,700

18,800

21,700

30

238

316

540

640

1,030

1,270

2,330

2,690

4,180

4,719

8,710

9,790

17,200

19,800

40

203

271

469

554

896

1,100

2,010

2,320

3,630

4,116

7,530

8,500

14,900

17,200

50

181

243

420

496

806

986

1,790

2,070

3,260

3,702

6,730

7,610

13,400

15,400

75

147

196

344

406

663

809

1,460

1,690

2,680

3,053

5,480

6,230

11,000

12,600

80

140

189

333

393

643

768

1,410

1,630

2,590

2,961

5,300

6,040

10,600

12,200

100

124

169

298

350

578

703

1,260

1,450

2,330

2,662

4,740

5,410

9,530

10,900

150

101

137

245

287

477

575

1,020

1,180

1,910

2,195

3,860

4,430

7,810

8,890

200

86

118

213

248

415

501

880

1,020

1,660

1,915

3,340

3,840

6,780

7,710

250

77

105

191

222

373

448

785

910

1,490

1,722

2,980

3,440

6,080

6,900

300

69

96

173

203

343

411

716

829

1,360

1,578

2,720

3,150

5,560

6,300

400

60

82

151

175

298

355

616

716

1,160

1,376

2,350

2,730

4,830

5,460

500

53

72

135

158

268

319

550

638

1,030

1,237

2,100

2,450

4,330

4,880

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table does not include effect of pressure drop across the line regulator. Where regulator loss exceeds 1/2 psi (based on 13 in. w.c. outlet pressure), DO NOT USE THIS TABLE. Consult with the regulator manufacturer for pressure drops and capacity factors. Pressure drops across a regulator may vary with flow rate.

2. CAUTION: Capacities shown in the table might exceed maximum capacity for a selected regulator. Consult with the regulator or tubing manufacturer for guidance.

3. Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends and/or fittings shall be increased by an equivalent length of tubing to the following equation: L = 1.3n where L is additional length (feet) of tubing and n is the number of additional fittings and/or bends.

4. EHD—Equivalent Hydraulic Diameter, which is a measure of the relative hydraulic efficiency between different tubing sizes. The greater the value of EHD, the greater the gas capacity of the tubing.

5. All table entries have been rounded to three significant digits.

TABLE 402.4(32)
CORRUGATED STAINLESS STEEL TUBING (CSST)

Gas

Undiluted Propane

Inlet Pressure

5.0 psi

Pressure Drop

3.5 psi

Specific Gravity

1.50

TUBE SIZE (EHD)

Flow
Designation

13

15

18

19

23

25

30

31

37

39

46

48

60

62

Length (ft)

Capacity in Thousands of Btu per Hour

10

826

1,070

1,710

2,060

3,150

4,000

7,830

8,950

13,100

14,441

28,600

31,200

54,400

63,800

25

509

664

1,090

1,310

2,040

2,550

4,860

5,600

8,400

9,339

18,000

19,900

34,700

40,400

30

461

603

999

1,190

1,870

2,340

4,430

5,100

7,680

8,564

16,400

18,200

31,700

36,900

40

396

520

867

1,030

1,630

2,030

3,820

4,400

6,680

7,469

14,200

15,800

27,600

32,000

50

352

463

777

926

1,460

1,820

3,410

3,930

5,990

6,717

12,700

14,100

24,700

28,600

75

284

376

637

757

1,210

1,490

2,770

3,190

4,920

5,539

10,300

11,600

20,300

23,400

80

275

363

618

731

1,170

1,450

2,680

3,090

4,770

5,372

9,990

11,200

19,600

22,700

100

243

324

553

656

1,050

1,300

2,390

2,760

4,280

4,830

8,930

10,000

17,600

20,300

150

196

262

453

535

866

1,060

1,940

2,240

3,510

3,983

7,270

8,210

14,400

16,600

200

169

226

393

464

755

923

1,680

1,930

3,050

3,474

6,290

7,130

12,500

14,400

250

150

202

352

415

679

828

1,490

1,730

2,740

3,124

5,620

6,390

11,200

12,900

300

136

183

322

379

622

757

1,360

1,570

2,510

2,865

5,120

5,840

10,300

11,700

400

117

158

279

328

542

657

1,170

1,360

2,180

2,498

4,430

5,070

8,920

10,200

500

104

140

251

294

488

589

1,050

1,210

1,950

2,247

3,960

4,540

8,000

9,110

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Notes:

1. Table does not include effect of pressure drop across line regulator. Where regulator loss exceeds1 psi, DO NOT USE THIS TABLE. Consult with the regulator manufacturer for pressure drops and capacity factors. Pressure drop across regulator may vary with the flow rate.

2. CAUTION: Capacities shown in the table might exceed maximum capacity of selected regulator. Consult with the tubing manufacturer for guidance.

3. Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends and/or fittings shall be increased by an equivalent length of tubing to the following equation: L = 1.3n where L is additional length (feet) of tubing and n is the number of additional fittings and/or bends.

4. EHD— Equivalent Hydraulic Diameter, which is a measure of the relative hydraulic efficiency between different tubing sizes. The greater the value of EHD, the greater the gas capacity of the tubing.

5. All table entries have been rounded to three significant digits.

TABLE 402.4(33)
POLYETHYLENE PLASTIC PIPE

Gas

Undiluted Propane

Inlet Pressure

11.0 in. w.c.

Pressure Drop

0.5 in. w.c.

Specific Gravity

1.50

INTENDED USE

PE pipe sizing between integral two-stage regulator at tank or second stage (low-pressure regulator) and building.

PIPE SIZE (inch)

Nominal OD

1/2

3/4

1

11/4

11/2

2

Designation

SDR 9.33

SDR 11.0

SDR 11.00

SDR 10.00

SDR 11.00

SDR 11.00

Actual ID

0.660

0.860

1.077

1.328

1.554

1.943

Length (ft)

Capacity in Thousands of Btu per Hour

10

340

680

1,230

2,130

3,210

5,770

20

233

468

844

1,460

2,210

3,970

30

187

375

677

1,170

1,770

3,180

40

160

321

580

1,000

1,520

2,730

50

142

285

514

890

1,340

2,420

60

129

258

466

807

1,220

2,190

70

119

237

428

742

1,120

2,010

80

110

221

398

690

1,040

1,870

90

103

207

374

648

978

1,760

100

98

196

353

612

924

1,660

125

87

173

313

542

819

1,470

150

78

157

284

491

742

1,330

175

72

145

261

452

683

1,230

200

67

135

243

420

635

1,140

250

60

119

215

373

563

1,010

300

54

108

195

338

510

916

350

50

99

179

311

469

843

400

46

92

167

289

436

784

450

43

87

157

271

409

736

500

41

82

148

256

387

695

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(34)
POLYETHYLENE PLASTIC PIPE

Gas

Undiluted Propane

Inlet Pressure

2.0 psi

Pressure Drop

1.0 psi

Specific Gravity

1.50

INTENDED USE

PE pipe sizing between 2 psig service regulator and line pressure regulator.

PIPE SIZE (inch)

Nominal OD

1/2

3/4

1

11/4

11/2

2

Designation

SDR 9.33

SDR 11.0

SDR 11.00

SDR 10.00

SDR 11.00

SDR 11.00

Actual ID

0.660

0.860

1.077

1.328

1.554

1.943

Length (ft)

Capacity in Thousands of Btu per Hour

10

3,130

6,260

11,300

19,600

29,500

53,100

20

2,150

4,300

7,760

13,400

20,300

36,500

30

1,730

3,450

6,230

10,800

16,300

29,300

40

1,480

2,960

5,330

9,240

14,000

25,100

50

1,310

2,620

4,730

8,190

12,400

22,200

60

1,190

2,370

4,280

7,420

11,200

20,100

70

1,090

2,180

3,940

6,830

10,300

18,500

80

1,010

2,030

3,670

6,350

9,590

17,200

90

952

1,910

3,440

5,960

9,000

16,200

100

899

1,800

3,250

5,630

8,500

15,300

125

797

1,600

2,880

4,990

7,530

13,500

150

722

1,450

2,610

4,520

6,830

12,300

175

664

1,330

2,400

4,160

6,280

11,300

200

618

1,240

2,230

3,870

5,840

10,500

250

548

1,100

1,980

3,430

5,180

9,300

300

496

994

1,790

3,110

4,690

8,430

350

457

914

1,650

2,860

4,320

7,760

400

425

851

1,530

2,660

4,020

7,220

450

399

798

1,440

2,500

3,770

6,770

500

377

754

1,360

2,360

3,560

6,390

550

358

716

1,290

2,240

3,380

6,070

600

341

683

1,230

2,140

3,220

5,790

650

327

654

1,180

2,040

3,090

5,550

700

314

628

1,130

1,960

2,970

5,330

750

302

605

1,090

1,890

2,860

5,140

800

292

585

1,050

1,830

2,760

4,960

850

283

566

1,020

1,770

2,670

4,800

900

274

549

990

1,710

2,590

4,650

950

266

533

961

1,670

2,520

4,520

1,000

259

518

935

1,620

2,450

4,400

1,100

246

492

888

1,540

2,320

4,170

1,200

234

470

847

1,470

2,220

3,980

1,300

225

450

811

1,410

2,120

3,810

1,400

216

432

779

1,350

2,040

3,660

1,500

208

416

751

1,300

1,960

3,530

1,600

201

402

725

1,260

1,900

3,410

1,700

194

389

702

1,220

1,840

3,300

1,800

188

377

680

1,180

1,780

3,200

1,900

183

366

661

1,140

1,730

3,110

2,000

178

356

643

1,110

1,680

3,020

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

TABLE 402.4(35)
POLYETHYLENE PLASTIC PIPE

Gas

Undiluted Propane

Inlet Pressure

11.0 in. w.c.

Pressure Drop

0.5 in. w.c.

Specific Gravity

1.50

INTENDED USE

PE pipe sizing between integral two-stage regulator at tank or second stage (low-pressure regulator) and building.

Plastic Tubing Size (CTS) (inch)

Nominal OD

1/2

1

Designation

SDR 7.00

SDR 11.00

Actual ID

0.445

0.927

Length (ft)

Capacity in Cubic Feet of Gas per Hour

10

121

828

20

83

569

30

67

457

40

57

391

50

51

347

60

46

314

70

42

289

80

39

269

90

37

252

100

35

238

125

31

211

150

28

191

175

26

176

200

24

164

225

22

154

250

21

145

275

20

138

300

19

132

350

18

121

400

16

113

450

15

106

500

15

100

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm,
1 pound per square inch = 6.895 kPa,
1-inch water column = 0.2488 kPa,
1 British thermal unit per hour = 0.2931 W,
1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.

Note: All table entries have been rounded to three significant digits.

The pipe size of each section of gas piping shall be determined using the longest length of piping from the point of delivery to the most remote outlet and the load of the section.

Pipe shall be sized as follows:

1. Pipe size of each section of the longest pipe run from the point of delivery to the most remote outlet shall be determined using the longest run of piping and the load of the section.

2. The pipe size of each section of branch piping not previously sized shall be determined using the length of piping from the point of delivery to the most remote outlet in each branch and the load of the section.

The pipe size for each section of higher pressure gas piping shall be determined using the longest length of piping from the point of delivery to the most remote line pressure regulator. The pipe size from the line pressure regulator to each outlet shall be determined using the length of piping from the regulator to the most remote outlet served by the regulator.
The design pressure loss in any piping system under maximum probable flow conditions, from the point of delivery to the inlet connection of the appliance, shall be such that the supply pressure at the appliance is greater than or equal to the minimum pressure required by the appliance.

The maximum design operating pressure for piping systems located inside buildings shall not exceed 5 pounds per square inch gauge (psig) (34 kPa gauge) except where one or more of the following conditions are met:

1. The piping system is welded.

2. The piping is located in a ventilated chase or otherwise enclosed for protection against accidental gas accumulation.

3. The piping is located inside buildings or separate areas of buildings used exclusively for:

3.1. Industrial processing or heating;

3.2. Research;

3.3. Warehousing; or

3.4. Boiler or mechanical rooms.

4. The piping is a temporary installation for buildings under construction.

5. The piping serves appliances or equipment used for agricultural purposes.

6. The piping system is an LP-gas piping system with a design operating pressure greater than 20 psi (137.9 kPa) and complies with NFPA 58.

LP-gas systems designed to operate below -5°F (-21°C) or with butane or a propane-butane mix shall be designed to either accommodate liquid LP-gas or prevent LP-gas vapor from condensing into a liquid.
Materials used for piping systems shall comply with the requirements of this chapter or shall be approved.
Pipe, fittings, valves and other materials shall not be used again except where they are free of foreign materials and have been ascertained to be adequate for the service intended.
Material not covered by the standards specifications listed herein shall be investigated and tested to determine that it is safe and suitable for the proposed service, and, in addition, shall be recommended for that service by the manufacturer and shall be approved by the code official.
Metallic pipe shall comply with Sections 403.4.1 through 403.4.4.
Cast-iron pipe shall not be used.

Steel and wrought-iron pipe shall be at least of standard weight (Schedule 40) and shall comply with one of the following standards:

1. ASME B 36.10, 10M;

2. ASTM A 53/A53M; or

3. ASTM A 106.

Copper and brass pipe shall not be used if the gas contains more than an average of 0.3 grains of hydrogen sulfide per 100 standard cubic feet of gas (0.7 milligrams per 100 liters). Threaded copper, brass and aluminum-alloy pipe shall not be used with gases corrosive to such materials.
Aluminum-alloy pipe shall comply with ASTM B 241 (except that the use of alloy 5456 is prohibited), and shall be marked at each end of each length indicating compliance. Aluminum-alloy pipe shall be coated to protect against external corrosion where it is in contact with masonry, plaster or insulation, or is subject to repeated wettings by such liquids as water, detergents or sewage. Aluminum-alloy pipe shall not be used in exterior locations or underground.
Seamless copper, aluminum alloy and steel tubing shall not be used with gases corrosive to such materials.
Steel tubing shall comply with ASTM A 254.

Copper tubing shall comply with Standard Type K or L of ASTM B 88 or ASTM B 280.

Copper and brass tubing shall not be used if the gas contains more than an average of 0.3 grains of hydrogen sulfide per 100 standard cubic feet of gas (0.7 milligrams per 100 liters).

Aluminum-alloy tubing shall comply with ASTM B 210 or ASTM B 241. Aluminum-alloy tubing shall be coated to protect against external corrosion where it is in contact with masonry, plaster or insulation, or is subject to repeated wettings by such liquids as water, detergent or sewage.

Aluminum-alloy tubing shall not be used in exterior locations or underground.

Corrugated stainless steel tubing shall be listed in accordance with ANSI LC 1/CSA 6.26.
Plastic pipe, tubing and fittings used to supply fuel gas shall conform to ASTM D 2513. Pipe shall be marked “Gas” and “ASTM D 2513.”

Plastic pipe, tubing and anodeless risers shall comply with the following:

1. Factory-assembled anodeless risers shall be recommended by the manufacturer for the gas used and shall be leak tested by the manufacturer in accordance with written procedures.

2. Service head adapters and field-assembled anodeless risers incorporating service head adapters shall be recommended by the manufacturer for the gas used, and shall be designed and certified to meet the requirements of Category I of ASTM D 2513, and U.S. Department of Transportation, Code of Federal Regulations, Title 49, Part 192.281(e). The manufacturer shall provide the user with qualified installation instructions as prescribed by the U.S. Department of Transportation, Code of Federal Regulations, Title 49, Part 192.283(b).

The use of plastic pipe, tubing and fittings in undiluted liquefied petroleum gas piping systems shall be in accordance with NFPA 58.
Plastic pipe, tubing and fittings used to connect regulator vents to remote vent terminations shall be PVC conforming to ANSI/UL 651. PVC vent piping shall not be installed indoors.

Pipe, tubing and fittings shall be clear and free from cutting burrs and defects in structure or threading, and shall be thoroughly brushed, and chip and scale blown.

Defects in pipe, tubing and fittings shall not be repaired. Defective pipe, tubing and fittings shall be replaced (see Section 406.1.2).

Where in contact with material or atmosphere exerting a corrosive action, metallic piping and fittings coated with a corrosion-resistant material shall be used. External or internal coatings or linings used on piping or components shall not be considered as adding strength.
Metallic pipe and fitting threads shall be taper pipe threads and shall comply with ASME B1.20.1.
Pipe with threads that are stripped, chipped, corroded or otherwise damaged shall not be used. Where a weld opens during the operation of cutting or threading, that portion of the pipe shall not be used.

Field threading of metallic pipe shall be in accordance with Table 403.9.2.

TABLE 403.9.2
SPECIFICATIONS FOR THREADING METALLIC PIPE

IRON PIPE SIZE
(inches)

APPROXIMATE LENGTH OF THREADED PORTION (inches)

APPROXIMATE NUMBER OF THREADS TO BE CUT

1/2

3/4

10

3/4

3/4

10

1

7/8

10

11/4

1

11

11/2

1

11

2

1

11

21/2

11/2

12

3

11/2

12

4

15/8

13

For SI: 1 inch = 25.4 mm.

Thread (joint) compounds (pipe dope) shall be resistant to the action of liquefied petroleum gas or to any other chemical constituents of the gases to be conducted through the piping.
The type of piping joint used shall be suitable for the pressure-temperature conditions and shall be selected giving consideration to joint tightness and mechanical strength under the service conditions. The joint shall be able to sustain the maximum end force caused by the internal pressure and any additional forces caused by temperature expansion or contraction, vibration, fatigue or the weight of the pipe and its contents.
Pipe joints shall be threaded, flanged, brazed or welded. Where nonferrous pipe is brazed, the brazing materials shall have a melting point in excess of 1,000°F (538°C). Brazing alloys shall not contain more than 0.05-percent phosphorus.
Tubing joints shall be made with approved gas tubing fittings, brazed with a material having a melting point in excess of 1,000°F (538°C) or made with press-connect fittings complying with ANSI LC-4. Brazing alloys shall not contain more than 0.05-percent phosphorus.
Flared joints shall be used only in systems constructed from nonferrous pipe and tubing where experience or tests have demonstrated that the joint is suitable for the conditions and where provisions are made in the design to prevent separation of the joints.

Metallic fittings shall comply with the following:

1. Threaded fittings in sizes larger than 4 inches (102 mm) shall not be used except where approved.

2. Fittings used with steel or wrought-iron pipe shall be steel, brass, bronze, malleable iron or cast iron.

3. Fittings used with copper or brass pipe shall be copper, brass or bronze.

4. Fittings used with aluminum-alloy pipe shall be of aluminum alloy.

5. Cast-iron fittings:

5.1. Flanges shall be permitted.

5.2. Bushings shall not be used.

5.3. Fittings shall not be used in systems containing flammable gas-air mixtures.

5.4. Fittings in sizes 4 inches (102 mm) and larger shall not be used indoors except where approved.

5.5. Fittings in sizes 6 inches (152 mm) and larger shall not be used except where approved.

6. Aluminum-alloy fittings. Threads shall not form the joint seal.

7. Zinc aluminum-alloy fittings. Fittings shall not be used in systems containing flammable gas-air mixtures.

8. Special fittings. Fittings such as couplings, proprietary-type joints, saddle tees, gland-type compression fittings, and flared, flareless or compression-type tubing fittings shall be: used within the fitting manufacturer’s pressure-temperature recommendations; used within the service conditions anticipated with respect to vibration, fatigue, thermal expansion or contraction; installed or braced to prevent separation of the joint by gas pressure or external physical damage; and shall be approved.

Plastic pipe, tubing and fittings shall be joined in accordance with the manufacturer’s instructions. Such joint shall comply with the following:

1. The joint shall be designed and installed so that the longitudinal pull-out resistance of the joint will be at least equal to the tensile strength of the plastic piping material.

2. Heat-fusion joints shall be made in accordance with qualified procedures that have been established and proven by test to produce gas-tight joints at least as strong as the pipe or tubing being joined. Joints shall be made with the joining method recommended by the pipe manufacturer. Heat fusion fittings shall be marked “ASTM D 2513.”

3. Where compression-type mechanical joints are used, the gasket material in the fitting shall be compatible with the plastic piping and with the gas distributed by the system. An internal tubular rigid stiffener shall be used in conjunction with the fitting. The stiffener shall be flush with the end of the pipe or tubing and shall extend at least to the outside end of the compression fitting when installed. The stiffener shall be free of rough or sharp edges and shall not be a force fit in the plastic. Split tubular stiffeners shall not be used.

4. Plastic piping joints and fittings for use in liquefied petroleum gas piping systems shall be in accordance with NFPA 58.

All flanges shall comply with ASME B16.1, ASME B16.20 or MSS SP-6. The pressure-temperature ratings shall equal or exceed that required by the application.
Standard facings shall be permitted for use under this code. Where 150-pound (1034 kPa) pressure-rated steel flanges are bolted to Class 125 cast-iron flanges, the raised face on the steel flange shall be removed.
Lapped flanges shall be used only above ground or in exposed locations accessible for inspection.
Material for gaskets shall be capable of withstanding the design temperature and pressure of the piping system, and the chemical constituents of the gas being conducted, without change to its chemical and physical properties. The effects of fire exposure to the joint shall be considered in choosing material. Acceptable materials include metal or metal-jacketed asbestos (plain or corrugated), asbestos, and aluminum “O” rings and spiral wound metal gaskets. When a flanged joint is opened, the gasket shall be replaced. Full-face gaskets shall be used with all bronze and cast-iron flanges.
Piping shall not be installed in or through a ducted supply, return or exhaust, or a clothes chute, chimney or gas vent, dumbwaiter or elevator shaft. Piping installed downstream of the point of delivery shall not extend through any townhouse unit other than the unit served by such piping.
Concealed piping shall not be located in solid partitions and solid walls, unless installed in a chase or casing.

Portions of a piping system installed in concealed locations shall not have unions, tubing fittings, right and left couplings, bushings, compression couplings and swing joints made by combinations of fittings.

Exceptions:

1. Tubing joined by brazing.

2. Fittings listed for use in concealed locations.

Gas piping shall not penetrate building foundation walls at any point below grade. Gas piping shall enter and exit a building at a point above grade and the annular space between the pipe and the wall shall be sealed.
In concealed locations, where piping other than black or galvanized steel is installed through holes or notches in wood studs, joists, rafters or similar members less than 11/2 inches (38 mm) from the nearest edge of the member, the pipe shall be protected by shield plates. Protective steel shield plates having a minimum thickness of 0.0575 inch (1.463 mm) (No. 16 gage) shall cover the area of the pipe where the member is notched or bored and shall extend a minimum of 4 inches (102 mm) above sole plates, below top plates and to each side of a stud, joist or rafter.
Piping in solid floors shall be laid in channels in the floor and covered in a manner that will allow access to the piping with a minimum amount of damage to the building. Where such piping is subject to exposure to excessive moisture or corrosive substances, the piping shall be protected in an approved manner. As an alternative to installation in channels, the piping shall be installed in a conduit of Schedule 40 steel, wrought iron, PVC or ABS pipe in accordance with Section 404.6.1 or 404.6.2.
The conduit shall extend into an occupiable portion of the building and, at the point where the conduit terminates in the building, the space between the conduit and the gas piping shall be sealed to prevent the possible entrance of any gas leakage. The conduit shall extend not less than 2 inches (51 mm) beyond the point where the pipe emerges from the floor. If the end sealing is capable of withstanding the full pressure of the gas pipe, the conduit shall be designed for the same pressure as the pipe. Such conduit shall extend not less than 4 inches (102 mm) outside the building, shall be vented above grade to the outdoors and shall be installed so as prevent the entrance of water and insects.
Where the conduit originates and terminates within the same building, the conduit shall originate and terminate in an accessible portion of the building and shall not be sealed. The conduit shall extend not less than 2 inches (51 mm) beyond the point where the pipe emerges from the floor.
All piping installed outdoors shall be elevated not less than 31/2 inches (152 mm) above ground and where installed across roof surfaces, shall be elevated not less than 31/2 inches (152 mm) above the roof surface. Piping installed above ground, outdoors, and installed across the surface of roofs shall be securely supported and located where it will be protected from physical damage. Where passing through an outside wall, the piping shall also be protected against corrosion by coating or wrapping with an inert material. Where piping is encased in a protective pipe sleeve, the annular space between the piping and the sleeve shall be sealed.
Metallic piping and metallic tubing that conveys fuel gas from an LP-gas storage container shall be provided with an approved dielectric fitting to electrically isolate the underground portion of the pipe or tube from the above ground portion that enters a building. Such dielectric fitting shall be installed above ground, outdoors.
Metallic pipe or tubing exposed to corrosive action, such as soil condition or moisture, shall be protected in an approved manner. Zinc coatings (galvanizing) shall not be deemed adequate protection for gas piping underground. Where dissimilar metals are joined underground, an insulating coupling or fitting shall be used. Piping shall not be laid in contact with cinders.
Uncoated threaded or socket welded joints shall not be used in piping in contact with soil or where internal or external crevice corrosion is known to occur.

Pipe protective coatings and wrappings shall be approved for the application and shall be factory applied.

Exception: Where installed in accordance with the manufacturer’s installation instructions, field application of coatings and wrappings shall be permitted for pipe nipples, fittings and locations where the factory coating or wrapping has been damaged or necessarily removed at joints.

Underground piping systems shall be installed a minimum depth of 12 inches (305 mm) below grade, except as provided for in Section 404.10.1.
Individual lines to outside lights, grills or other appliances shall be installed a minimum of 8 inches (203 mm) below finished grade, provided that such installation is approved and is installed in locations not susceptible to physical damage.
The trench shall be graded so that the pipe has a firm, substantially continuous bearing on the bottom of the trench.
Piping installed underground beneath buildings is prohibited except where the piping is encased in a conduit of wrought iron, plastic pipe, steel pipe or other approved conduit material designed to withstand the superimposed loads. The conduit shall be protected from corrosion in accordance with Section 404.9 and shall be installed in accordance with Section 404.12.1 or 404.12.2.
The conduit shall extend into an occupiable portion of the building and, at the point where the conduit terminates in the building, the space between the conduit and the gas piping shall be sealed to prevent the possible entrance of any gas leakage. The conduit shall extend not less than 2 inches (51 mm) beyond the point where the pipe emerges from the floor. Where the end sealing is capable of withstanding the full pressure of the gas pipe, the conduit shall be designed for the same pressure as the pipe. Such conduit shall extend not less than 4 inches (102 mm) outside of the building, shall be vented above grade to the outdoors and shall be installed so as to prevent the entrance of water and insects.
Where the conduit originates and terminates within the same building, the conduit shall originate and terminate in an accessible portion of the building and shall not be sealed. The conduit shall extend not less than 2 inches (51 mm) beyond the point where the pipe emerges from the floor.

Gas outlets that do not connect to appliances shall be capped gas tight.

Exception: Listed and labeled flush-mounted-type quick- disconnect devices and listed and labeled gas convenience outlets shall be installed in accordance with the manufacturer’s installation instructions.

The unthreaded portion of piping outlets shall extend not less than l inch (25 mm) through finished ceilings and walls and where extending through floors or outdoor patios and slabs, shall not be less than 2 inches (51 mm) above them. The outlet fitting or piping shall be securely supported. Outlets shall not be placed behind doors. Outlets shall be located in the room or space where the appliance is installed.

Exception: Listed and labeled flush-mounted-type quick- disconnect devices and listed and labeled gas convenience outlets shall be installed in accordance with the manufacturer’s installation instructions.

The installation of plastic pipe shall comply with Sections 404.15.1 through 404.15.3.

Plastic pipe shall be installed outdoors underground only. Plastic pipe shall not be used within or under any building or slab or be operated at pressures greater than 100 psig (689 kPa) for natural gas or 30 psig (207 kPa) for LP-gas.

Exceptions:

1. Plastic pipe shall be permitted to terminate above ground outside of buildings where installed in premanufactured anodeless risers or service head adapter risers that are installed in accordance with the manufacturer’s installation instructions.

2. Plastic pipe shall be permitted to terminate with a wall head adapter within buildings where the plastic pipe is inserted in a piping material for fuel gas use in buildings.

3. Plastic pipe shall be permitted under outdoor patio, walkway and driveway slabs provided that the burial depth complies with Section 404.10.

Connections made outdoors and underground between metallic and plastic piping shall be made only with transition fittings conforming with ASTM D 2513 Category I or ASTM F 1973.
A yellow insulated copper tracer wire or other approved conductor shall be installed adjacent to underground nonmetallic piping. Access shall be provided to the tracer wire or the tracer wire shall terminate above ground at each end of the nonmetallic piping. The tracer wire size shall not be less than 18 AWG and the insulation type shall be suitable for direct burial.

A device shall not be placed inside the piping or fittings that will reduce the cross-sectional area or otherwise obstruct the free flow of gas.

Exception: Approved gas filters.

Before any system of piping is put in service or concealed, it shall be tested to ensure that it is gas tight. Testing, inspection and purging of piping systems shall comply with Section 406.
Changes in direction of pipe shall be permitted to be made by the use of fittings, factory bends or field bends.

Metallic pipe bends shall comply with the following:

1. Bends shall be made only with bending tools and procedures intended for that purpose.

2. All bends shall be smooth and free from buckling, cracks or other evidence of mechanical damage.

3. The longitudinal weld of the pipe shall be near the neutral axis of the bend.

4. Pipe shall not be bent through an arc of more than 90 degrees (1.6 rad).

5. The inside radius of a bend shall be not less than six times the outside diameter of the pipe.

Plastic pipe bends shall comply with the following:

1. The pipe shall not be damaged and the internal diameter of the pipe shall not be effectively reduced.

2. Joints shall not be located in pipe bends.

3. The radius of the inner curve of such bends shall not be less than 25 times the inside diameter of the pipe.

4. Where the piping manufacturer specifies the use of special bending tools or procedures, such tools or procedures shall be used.

Factory-made welding elbows or transverse segments cut therefrom shall have an arc length measured along the crotch at least 1 inch (25 mm) in pipe sizes 2 inches (51 mm) and larger.
Prior to acceptance and initial operation, all piping installations shall be inspected and pressure tested to determine that the materials, design, fabrication and installation practices comply with the requirements of this code.
Inspection shall consist of visual examination, during or after manufacture, fabrication, assembly or pressure tests as appropriate. Supplementary types of nondestructive inspection techniques, such as magnetic-particle, radiographic, ultrasonic, etc., shall not be required unless specifically listed herein or in the engineering design.

In the event repairs or additions are made after the pressure test, the affected piping shall be tested.

Minor repairs and additions are not required to be pressure tested provided that the work is inspected and connections are tested with a noncorrosive leak-detecting fluid or other approved leak-detecting methods.

Where new branches are installed to new appliances, only the newly installed branches shall be required to be pressure tested. Connections between the new piping and the existing piping shall be tested with a noncorrosive leak-detecting fluid or other approved leak-detecting methods.
A piping system shall be permitted to be tested as a complete unit or in sections. Under no circumstances shall a valve in a line be used as a bulkhead between gas in one section of the piping system and test medium in an adjacent section, unless two valves are installed in series with a valved “telltale” located between these valves. A valve shall not be subjected to the test pressure unless it can be determined that the valve, including the valve-closing mechanism, is designed to safely withstand the test pressure.
Regulator and valve assemblies fabricated independently of the piping system in which they are to be installed shall be permitted to be tested with inert gas or air at the time of fabrication.
The test medium shall be air, nitrogen, carbon dioxide or an inert gas. Oxygen shall not be used.

Pipe joints, including welds, shall be left exposed for examination during the test.

Exception: Covered or concealed pipe end joints that have been previously tested in accordance with this code.

Expansion joints shall be provided with temporary restraints, if required, for the additional thrust load under test.
Appliances and equipment that are not to be included in the test shall be either disconnected from the piping or isolated by blanks, blind flanges or caps. Flanged joints at which blinds are inserted to blank off other equipment during the test shall not be required to be tested.
Where the piping system is connected to appliances or equipment designed for operating pressures of less than the test pressure, such appliances or equipment shall be isolated from the piping system by disconnecting them and capping the outlet(s).
Where the piping system is connected to appliances or equipment designed for operating pressures equal to or greater than the test pressure, such appliances or equipment shall be isolated from the piping system by closing the individual appliance or equipment shutoff valve(s).
All testing of piping systems shall be done with due regard for the safety of employees and the public during the test. Bulkheads, anchorage, and bracing suitably designed to resist test pressures shall be installed if necessary. Prior to testing, the interior of the pipe shall be cleared of all foreign material.
Test pressure shall be measured with a manometer or with a pressure-measuring device designed and calibrated to read, record or indicate a pressure loss caused by leakage during the pressure test period. The source of pressure shall be isolated before the pressure tests are made. Mechanical gauges used to measure test pressures shall have a range such that the highest end of the scale is not greater than five times the test pressure.
The test pressure to be used shall be no less than 11/2 times the proposed maximum working pressure, but not less than 3 psig (20 kPa gauge), irrespective of design pressure. Where the test pressure exceeds 125 psig (862 kPa gauge), the test pressure shall not exceed a value that produces a hoop stress in the piping greater than 50 percent of the specified minimum yield strength of the pipe.
Test duration shall be not less than 1/2 hour for each 500 cubic feet (14 m3) of pipe volume or fraction thereof. When testing a system having a volume less than 10 cubic feet (0.28 m3) or a system in a single-family dwelling, the test duration shall be not less than 10 minutes. The duration of the test shall not be required to exceed 24 hours.

The piping system shall withstand the test pressure specified without showing any evidence of leakage or other defects.

Any reduction of test pressures as indicated by pressure gauges shall be deemed to indicate the presence of a leak unless such reduction can be readily attributed to some other cause.

The leakage shall be located by means of an approved gas detector, a noncorrosive leak detection fluid or other approved leak detection methods. Matches, candles, open flames or other methods that could provide a source of ignition shall not be used.
Where leakage or other defects are located, the affected portion of the piping system shall be repaired or replaced and retested.
Leakage checking of systems and equipment shall be in accordance with Sections 406.6.1 through 406.6.4.
Leak checks using fuel gas shall be permitted in piping systems that have been pressure tested in accordance with Section 406.
During the process of turning gas on into a system of new gas piping, the entire system shall be inspected to determine that there are no open fittings or ends and that all valves at unused outlets are closed and plugged or capped.
Immediately after the gas is turned on into a new system or into a system that has been initially restored after an interruption of service, the piping system shall be checked for leakage. Where leakage is indicated, the gas supply shall be shut off until the necessary repairs have been made.
Appliances and equipment shall not be placed in operation until after the piping system has been checked for leakage in accordance with Section 406.6.3 and determined to be free of leakage and purged in accordance with Section 406.7.2.
Purging of piping shall comply with Sections 406.7.1 through 406.7.4.

Where gas piping is to be opened for servicing, addition or modification, the section to be worked on shall be turned off from the gas supply at the nearest convenient point, and the line pressure vented to the outdoors, or to ventilated areas of sufficient size to prevent accumulation of flammable mixtures.

The remaining gas in this section of pipe shall be displaced with an inert gas as required by Table 406.7.1.

TABLE 406.7.1
LENGTH OF PIPING REQUIRING PURGING WITH
INERT GAS FOR SERVICING OR MODIFICATION

NOMINAL PIPE SIZE
(inches)

LENGTH OF PIPING
REQUIRING PURGING

21/2

> 50 feet

3

> 30 feet

4

> 15 feet

6

> 10 feet

8 or larger

Any length

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

Where piping full of air is placed in operation, the air in the piping shall be displaced with fuel gas, except where such piping is required by Table 406.7.2 to be purged with an inert gas prior to introduction of fuel gas. The air can be safely displaced with fuel gas provided that a moderately rapid and continuous flow of fuel gas is introduced at one end of the line and air is vented out at the other end. The fuel gas flow shall be continued without interruption until the vented gas is free of air. The point of discharge shall not be left unattended during purging. After purging, the vent shall then be closed. Where required by Table 406.7.2, the air in the piping shall first be displaced with an inert gas, and the inert gas shall then be displaced with fuel gas.

TABLE 406.7.2
LENGTH OF PIPING REQUIRING PURGING WITH
INERT GAS BEFORE PLACING IN OPERATION

NOMINAL PIPE SIZE
(inches)

LENGTH OF PIPING
REQUIRING PURGING

3

> 30 feet

4

> 15 feet

6

> 10 feet

8 or larger

Any length

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

The open end of piping systems being purged shall not discharge into confined spaces or areas where there are sources of ignition unless precautions are taken to perform this operation in a safe manner by ventilation of the space, control of purging rate and elimination of all hazardous conditions.
After the piping system has been placed in operation, all appliances and equipment shall be purged and then placed in operation, as necessary.
Piping shall be provided with support in accordance with Section 407.2.
Piping shall be supported with metal pipe hooks, metal pipe straps, metal bands, metal brackets, metal hangers or building structural components, suitable for the size of piping, of adequate strength and quality, and located at intervals so as to prevent or damp out excessive vibration. Piping shall be anchored to prevent undue strains on connected appliances and shall not be supported by other piping. Pipe hangers and supports shall conform to the requirements of MSS SP-58 and shall be spaced in accordance with Section 415. Supports, hangers and anchors shall be installed so as not to interfere with the free expansion and contraction of the piping between anchors. All parts of the supporting equipment shall be designed and installed so they will not be disengaged by movement of the supported piping.
Piping for other than dry gas conditions shall be sloped not less than 1/4 inch in 15 feet (6.3 mm in 4572 mm) to prevent traps.
Where wet gas exists, a drip shall be provided at any point in the line of pipe where condensate could collect. A drip shall also be provided at the outlet of the meter and shall be installed so as to constitute a trap wherein an accumulation of condensate will shut off the flow of gas before the condensate will run back into the meter.
Drips shall be provided with ready access to permit cleaning or emptying. A drip shall not be located where the condensate is subject to freezing.
Where a sediment trap is not incorporated as part of the appliance, a sediment trap shall be installed downstream of the appliance shutoff valve as close to the inlet of the appliance as practical. The sediment trap shall be either a tee fitting having a capped nipple of any length installed vertically in the bottommost opening of the tee or other device approved as an effective sediment trap. Illuminating appliances, ranges, clothes dryers and outdoor grills need not be so equipped.
Piping systems shall be provided with shutoff valves in accordance with this section.

Shutoff valves shall be of an approved type; shall be constructed of materials compatible with the piping; and shall comply with the standard that is applicable for the pressure and application, in accordance with Table 409.1.1.

TABLE 409.1.1
MANUAL GAS VALVE STANDARDS

VALVE STANDARDS

APPLIANCE SHUTOFF VALVE APPLICATION UP TO 1/2 psig PRESSURE

OTHER VALVE APPLICATIONS

UP TO 1/2 psig PRESSURE

UP TO 2 psig PRESSURE

UP TO 5 psig PRESSURE

UP TO 125 psig PRESSURE

ANSI Z21.15

X

CSA Requirement 3-88

X

X

Xa

Xb

ASME B16.44

X

X

Xa

Xb

ASME B16.33

X

X

X

X

X

For SI: 1 pound per square inch gauge = 6.895 kPa.

a. If labeled 2G.

b. If labeled 5G.

Shutoff valves shall be prohibited in concealed locations and furnace plenums.
Shutoff valves shall be located in places so as to provide access for operation and shall be installed so as to be protected from damage.
Every meter shall be equipped with a shutoff valve located on the supply side of the meter.
Where a single meter is used to supply gas to more than one building or tenant, a separate shutoff valve shall be provided for each building or tenant.
In multiple tenant buildings, where a common piping system is installed to supply other than one- and two-family dwellings, shutoff valves shall be provided for each tenant. Each tenant shall have access to the shutoff valve serving that tenant’s space.
In a common system serving more than one building, shutoff valves shall be installed outdoors at each building.
Each house line shutoff valve shall be plainly marked with an identification tag attached by the installer so that the piping systems supplied by such valves are readily identified.
A listed shutoff valve shall be installed immediately ahead of each MP regulator.
Each appliance shall be provided with a shutoff valve in accordance with Section 409.5.1, 409.5.2 or 409.5.3.
The shutoff valve shall be located in the same room as the appliance. The shutoff valve shall be within 6 feet (1829 mm) of the appliance, and shall be installed upstream of the union, connector or quick disconnect device it serves. Such shutoff valves shall be provided with access. Appliance shutoff valves located in the firebox of a fireplace shall be installed in accordance with the appliance manufacturer’s instructions.
Shutoff valves for vented decorative appliances, room heaters and decorative appliances for installation in vented fireplaces shall be permitted to be installed in an area remote from the appliances where such valves are provided with ready access. Such valves shall be permanently identified and shall serve no other appliance. The piping from the shutoff valve to within 6 feet (1829 mm) of the appliance shall be designed, sized and installed in accordance with Sections 401 through 408.
Where the appliance shutoff valve is installed at a manifold, such shutoff valve shall be located within 50 feet (15 240 mm) of the appliance served and shall be readily accessible and permanently identified. The piping from the manifold to within 6 feet (1829 mm) of the appliance shall be designed, sized and installed in accordance with Sections 401 through 408.
Where provided with two or more fuel gas outlets, including table-, bench- and hood-mounted outlets, each laboratory space in educational, research, commercial and industrial occupancies shall be provided with a single dedicated shutoff valve through which all such gas outlets shall be supplied. The dedicated shutoff valve shall be readily accessible, located within the laboratory space served, located adjacent to the egress door from the space and shall be identified by approved signage stating “Gas Shutoff.”
A line pressure regulator shall be installed where the appliance is designed to operate at a lower pressure than the supply pressure. Line gas pressure regulators shall be listed as complying with ANSI Z21.80. Access shall be provided to pressure regulators. Pressure regulators shall be protected from physical damage. Regulators installed on the exterior of the building shall be approved for outdoor installation.

MP pressure regulators shall comply with the following:

1. The MP regulator shall be approved and shall be suitable for the inlet and outlet gas pressures for the application.

2. The MP regulator shall maintain a reduced outlet pressure under lockup (no-flow) conditions.

3. The capacity of the MP regulator, determined by published ratings of its manufacturer, shall be adequate to supply the appliances served.

4. The MP pressure regulator shall be provided with access. Where located indoors, the regulator shall be vented to the outdoors or shall be equipped with a leak-limiting device, in either case complying with Section 410.3.

5. A tee fitting with one opening capped or plugged shall be installed between the MP regulator and its upstream shutoff valve. Such tee fitting shall be positioned to allow connection of a pressure-measuring instrument and to serve as a sediment trap.

6. A tee fitting with one opening capped or plugged shall be installed not less than 10 pipe diameters downstream of the MP regulator outlet. Such tee fitting shall be positioned to allow connection of a pressure-measuring instrument.

Pressure regulators that require a vent shall be vented directly to the outdoors. The vent shall be designed to prevent the entry of insects, water and foreign objects.

Exception: A vent to the outdoors is not required for regulators equipped with and labeled for utilization with an approved vent-limiting device installed in accordance with the manufacturer’s instructions.

Vent piping for relief vents and breather vents shall be constructed of materials allowed for gas piping in accordance with Section 403. Vent piping shall be not smaller than the vent connection on the pressure regulating device. Vent piping serving relief vents and combination relief and breather vents shall be run independently to the outdoors and shall serve only a single device vent. Vent piping serving only breather vents is permitted to be connected in a manifold arrangement where sized in accordance with an approved design that minimizes back pressure in the event of diaphragm rupture. Regulator vent piping shall not exceed the length specified in the regulator manufacturer’s installation instructions.

Except as required by Section 411.1.1, appliances shall be connected to the piping system by one of the following:

1. Rigid metallic pipe and fittings.

2. Corrugated stainless steel tubing (CSST) where installed in accordance with the manufacturer’s instructions.

3. Semirigid metallic tubing and metallic fittings. Lengths shall not exceed 6 feet (1829 mm) and shall be located entirely in the same room as the appliance. Semirigid metallic tubing shall not enter a motor-operated appliance through an unprotected knockout opening.

4. Listed and labeled appliance connectors in compliance with ANSI Z21.24 and installed in accordance with the manufacturer’s installation instructions and located entirely in the same room as the appliance.

5. Listed and labeled quick-disconnect devices used in conjunction with listed and labeled appliance connectors.

6. Listed and labeled convenience outlets used in conjunction with listed and labeled appliance connectors.

7. Listed and labeled outdoor appliance connectors in compliance with ANSI Z21.75/CSA 6.27 and installed in accordance with the manufacturer’s installation instructions.

Commercial cooking appliances installed on casters and appliances that are moved for cleaning and sanitation purposes shall be connected to the piping system with an appliance connector listed as complying with ANSI Z21.69 or in accordance with Item 1 or 3 of Section 411.1.
Connectors and tubing shall be installed so as to be protected against physical damage.
Appliance fuel connectors shall be installed in accordance with the manufacturer’s instructions and Sections 411.1.3.1 through 411.1.3.4.

Connectors shall have an overall length not to exceed 6 feet (1829 mm). Measurement shall be made along the centerline of the connector. Only one connector shall be used for each appliance.

Exception: Rigid metallic piping used to connect an appliance to the piping system shall be permitted to have a total length greater than 6 feet (1829 mm), provided that the connecting pipe is sized as part of the piping system in accordance with Section 402 and the location of the appliance shutoff valve complies with Section 409.5.

Connectors shall have the capacity for the total demand of the connected appliance.

Connectors shall not be concealed within, or extended through, walls, floors, partitions, ceilings or appliance housings.

Exceptions:

1. Connectors constructed of materials allowed for piping systems in accordance with Section 403 shall be permitted to pass through walls, floors, partitions and ceilings where installed in accordance with Section 409.5.2 or 409.5.3.

2. Rigid steel pipe connectors shall be permitted to extend through openings in appliance housings.

3. Fireplace inserts that are factory equipped with grommets, sleeves or other means of protection in accordance with the listing of the appliance.

4. Semirigid tubing and listed connectors shall be permitted to extend through an opening in an appliance housing, cabinet or casing where the tubing or connector is protected against damage.

A shutoff valve not less than the nominal size of the connector shall be installed ahead of the connector in accordance with Section 409.5.
Where appliances are equipped with casters or are otherwise subject to periodic movement or relocation for purposes such as routine cleaning and maintenance, such appliances shall be connected to the supply system piping by means of an approved flexible connector designed and labeled for the application. Such flexible connectors shall be installed and protected against physical damage in accordance with the manufacturer’s installation instructions.
Internal combustion engines shall not be rigidly connected to the gas supply piping.
A union fitting shall be provided for appliances connected by rigid metallic pipe. Such unions shall be accessible and located within 6 feet (1829 mm) of the appliance.

Manufactured homes shall be connected to the distribution piping system by one of the following materials:

1. Metallic pipe in accordance with Section 403.4.

2. Metallic tubing in accordance with Section 403.5.

3. Listed and labeled connectors in compliance with ANSI Z21.75/CSA 6.27 and installed in accordance with the manufacturer’s installation instructions.

Suspended low-intensity infrared tube heaters shall be connected to the building piping system with a connector listed for the application complying with ANSI Z21.24/CGA 6.10. The connector shall be installed as specified by the tube heater manufacturer’s instructions.
Motor fuel-dispensing facilities for LP-gas fuel shall be in accordance with this section and the International Fire Code. The operation of LP-gas motor fuel-dispensing facilities shall be regulated by the International Fire Code.
Storage vessels and equipment used for the storage or dispensing of LP-gas shall be approved or listed in accordance with Sections 412.3 and 412.4.
Containers; pressure-relief devices, including pressure-relief valves; and pressure regulators and piping used for LP-gas shall be approved.
Hoses, hose connections, vehicle fuel connections, dispensers, LP-gas pumps and electrical equipment used for LP-gas shall be listed.
Motor vehicle fueling operations shall be conducted by qualified attendants or in accordance with Section 412.8 by persons trained in the proper handling of LP-gas.

In addition to the fuel dispensing requirements of the International Fire Code, the point of transfer for dispensing operations shall be 25 feet (7620 mm) or more from buildings having combustible exterior wall surfaces, buildings having noncombustible exterior wall surfaces that are not part of a 1-hour fire-resistance-rated assembly or buildings having combustible overhangs, property which could be built on public streets, or sidewalks and railroads; and at least 10 feet (3048 mm) from driveways and buildings having noncombustible exterior wall surfaces that are part of a fire-resistance-rated assembly having a rating of 1 hour or more.

Exception: The point of transfer for dispensing operations need not be separated from canopies providing weather protection for the dispensing equipment constructed in accordance with the International Building Code.

Liquefied petroleum gas containers shall be located in accordance with the International Fire Code. Liquefied petroleum gas storage and dispensing equipment shall be located outdoors and in accordance with the International Fire Code.

The installation and operation of LP-gas dispensing systems shall be in accordance with this section and the International Fire Code. Liquefied petroleum gas dispensers and dispensing stations shall be installed in accordance with manufacturers’ specifications and their listing.

A manual shutoff valve and an excess flow-control check valve shall be located in the liquid line between the pump and the dispenser inlet where the dispensing device is installed at a remote location and is not part of a complete storage and dispensing unit mounted on a common base.

An excess flow-control check valve or an emergency shutoff valve shall be installed in or on the dispenser at the point at which the dispenser hose is connected to the liquid piping. A differential backpressure valve shall be considered equivalent protection. A listed shutoff valve shall be located at the discharge end of the transfer hose.

Hoses and piping for the dispensing of LP-gas shall be provided with hydrostatic relief valves. The hose length shall not exceed 18 feet (5486 mm). An approved method shall be provided to protect the hose against mechanical damage.
Vehicle impact protection for LP-gas storage containers, pumps and dispensers shall be provided in accordance with the International Fire Code.
Self-service LP-gas dispensing systems, including key, code and card lock dispensing systems, shall not be open to the public and shall be limited to the filling of permanently mounted fuel containers on LP-gas powered vehicles. In addition to the requirements in the International Fire Code, self-service LP-gas dispensing systems shall be provided with an emergency shutoff switch located within 100 feet (30 480 mm) of, but not less than 20 feet (6096 mm) from, dispensers and the owner of the dispensing facility shall ensure the safe operation of the system and the training of users.
Motor fuel-dispensing facilities for CNG fuel shall be in accordance with this section and the International Fire Code. The operation of CNG motor fuel-dispensing facilities shall be regulated by the International Fire Code.
Storage vessels and equipment used for the storage, compression or dispensing of CNG shall be approved or listed in accordance with Sections 413.2.1 through 413.2.3.
Containers; compressors; pressure-relief devices, including pressure-relief valves; and pressure regulators and piping used for CNG shall be approved.
Hoses, hose connections, dispensers, gas detection systems and electrical equipment used for CNG shall be listed. Vehicle fueling connections shall be listed and labeled.
Residential fueling appliances shall be listed. The capacity of a residential fueling appliance shall not exceed 5 standard cubic feet per minute (0.14 standard cubic meter/min) of natural gas.

Compression, storage and dispensing equipment shall be located above ground outside.

Exceptions:

1. Compression, storage or dispensing equipment is allowed in buildings of noncombustible construction, as set forth in the International Building Code, which are unenclosed for three-quarters or more of the perimeter.

2. Compression, storage and dispensing equipment is allowed to be located indoors or in vaults in accordance with the International Fire Code.

3. Residential fueling appliances and equipment shall be allowed to be installed indoors in accordance with the equipment manufacturer’s instructions and Section 413.4.3.

In addition to the fuel-dispensing requirements of the International Fire Code, compression, storage and dispensing equipment not located in vaults complying with the International Fire Code and other than residential fueling appliances shall not be installed:

1. Beneath power lines.

2. Less than 10 feet (3048 mm) from the nearest building or property line that could be built on, public street, sidewalk or source of ignition.

Exception: Dispensing equipment need not be separated from canopies that provide weather protection for the dispensing equipment and are constructed in accordance with the International Building Code.

3. Less than 25 feet (7620 mm) from the nearest rail of any railroad track.

4. Less than 50 feet (15 240 mm) from the nearest rail of any railroad main track or any railroad or transit line where power for train propulsion is provided by an outside electrical source, such as third rail or overhead catenary.

5. Less than 50 feet (15 240 mm) from the vertical plane below the nearest overhead wire of a trolley bus line.

Residential fueling appliances shall be installed in accordance with Sections 413.4.1 through 413.4.3.
Residential fueling appliances shall be connected to the premises’ gas piping system without causing damage to the piping system or the connection to the internal appliance apparatus.
Residential fueling appliances located outdoors shall be installed on a firm, noncombustible base.
Where located indoors, residential fueling appliances shall be vented to the outdoors. A gas detector set to operate at one-fifth of the lower limit of flammability of natural gas shall be installed in the room or space containing the appliance. The detector shall be located within 6 inches (152 mm) of the highest point in the room or space. The detector shall stop the operation of the appliance and activate an audible or a visual alarm.

Self-service CNG-dispensing systems, including key, code and card lock dispensing systems, shall be limited to the filling of permanently mounted fuel containers on CNG-powered vehicles.

In addition to the requirements in the International Fire Code, the owner of a self-service CNG-dispensing facility shall ensure the safe operation of the system and the training of users.

Pressure regulators shall be designed, installed or protected so their operation will not be affected by the elements (freezing rain, sleet, snow, ice, mud or debris). This protection is allowed to be integral with the regulator.
Piping to equipment shall be provided with a remote manual shutoff valve. Such valve shall be provided with ready access.
An emergency shutdown device shall be located within 75 feet (22 860 mm) of, but not less than 25 feet (7620 mm) from, dispensers and shall also be provided in the compressor area. Upon activation, the emergency shutdown system shall automatically shut off the power supply to the compressor and close valves between the main gas supply and the compressor and between the storage containers and dispensers.
The discharge of CNG from motor vehicle fuel cylinders for the purposes of maintenance, cylinder certification, calibration of dispensers or other activities shall be in accordance with this section. The discharge of CNG from motor vehicle fuel cylinders shall be accomplished through a closed transfer system or an approved method of atmospheric venting in accordance with Section 413.9.1 or 413.9.2.
A documented procedure which explains the logical sequence for discharging the cylinder shall be provided to the code official for review and approval. The procedure shall include what actions the operator will take in the event of a low-pressure or high-pressure natural gas release during the discharging activity. A drawing illustrating the arrangement of piping, regulators and equipment settings shall be provided to the code official for review and approval. The drawing shall illustrate the piping and regulator arrangement and shall be shown in spatial relation to the location of the compressor, storage vessels and emergency shutdown devices.
Atmospheric venting of motor vehicle fuel cylinders shall be in accordance with Sections 413.9.2.1 through 413.9.2.6.
A drawing illustrating the location of the vessel support, piping, the method of grounding and bonding, and other requirements specified herein shall be provided to the code official for review and approval.
A method of rigidly supporting the vessel during the venting of CNG shall be provided. The selected method shall provide not less than two points of support and shall prevent the horizontal and lateral movement of the vessel. The system shall be designed to prevent the movement of the vessel based on the highest gas-release velocity through valve orifices at the vessel’s rated pressure and volume. The structure or appurtenance shall be constructed of noncombustible materials.

The structure or appurtenance used for stabilizing the cylinder shall be separated from the site equipment, features and exposures and shall be located in accordance with Table 413.9.2.3.

[F] TABLE 413.9.2.3
SEPARATION DISTANCE FOR
ATMOSPHERIC VENTING OF CNG

EQUIPMENT OR FEATURE

MINIMUM
SEPARATION (feet)

Buildings

25

Building openings

25

Lot lines

15

Public ways

15

Vehicles

25

CNG compressor and storage vessels

25

CNG dispensers

25

For SI: 1 foot = 304.8 mm.

The structure or appurtenance used for supporting the cylinder shall be grounded in accordance with NFPA 70. The cylinder valve shall be bonded prior to the commencement of venting operations.

A vent tube that will divert the gas flow to the atmosphere shall be installed on the cylinder prior to the commencement of the venting and purging operation. The vent tube shall be constructed of pipe or tubing materials approved for use with CNG in accordance with the International Fire Code.

The vent tube shall be capable of dispersing the gas a minimum of 10 feet (3048 mm) above grade level. The vent tube shall not be provided with a rain cap or other feature which would limit or obstruct the gas flow.

At the connection fitting of the vent tube and the CNG cylinder, a listed bidirectional detonation flame arrester shall be provided.

Approved NO SMOKING signs shall be posted within 10 feet (3048 mm) of the cylinder support structure or appurtenance. Approved CYLINDER SHALL BE BONDED signs shall be posted on the cylinder support structure or appurtenance.
Where air or oxygen under pressure is used in connection with the gas supply, effective means such as a backpressure regulator and relief valve shall be provided to prevent air or oxygen from passing back into the gas piping. Where oxygen is used, installation shall be in accordance with NFPA 51.
Where supplementary gas for standby use is connected downstream from a meter or a service regulator where a meter is not provided, a device to prevent backflow shall be installed. A three-way valve installed to admit the standby supply and at the same time shut off the regular supply shall be permitted to be used for this purpose.

Piping shall be supported at intervals not exceeding the spacing specified in Table 415.1. Spacing of supports for CSST shall be in accordance with the CSST manufacturer’s instructions.

TABLE 415.1
SUPPORT OF PIPING

STEEL PIPE,
NOMINAL SIZE
OF PIPE
(inches)

SPACING OF SUPPORTS
(feet)

NOMINAL SIZE OF TUBING
(SMOOTH-WALL)
(inch O.D.)

SPACING OF SUPPORTS
(feet)

1/2

6

1/2

4

3/4 or 1

8

5/8 or 3/4

6

11/4 or larger
(horizontal)

10

7/8 or 1 (horizontal)

8

11/4 or larger
(vertical)

Every floor level

1 or larger (vertical)

Every floor level

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

Overpressure protection devices shall be provided in accordance with this section to prevent the pressure in the piping system from exceeding the pressure that would cause unsafe operation of any connected and properly adjusted appliances.

The requirements of this section shall be considered to be met and a piping system deemed to have overpressure protection where a service or line pressure regulator plus one other device are installed such that the following occur:

1. Each device limits the pressure to a value that does not exceed the maximum working pressure of the downstream system.

2. The individual failure of either device does not result in the overpressurization of the downstream system.

The pressure regulating, limiting and relieving devices shall be properly maintained; and inspection procedures shall be devised or suitable instrumentation installed to detect failures or malfunctions of such devices; and replacements or repairs shall be promptly made.

A pressure-relieving or pressure-limiting device shall not be required where: (1) the gas does not contain materials that could seriously interfere with the operation of the service or line pressure regulator; (2) the operating pressure of the gas source is 60 psi (414 kPa) or less; and (3) the service or line pressure regulator has all of the following design features or characteristics:

1. Pipe connections to the service or line regulator do not exceed 2 inches (51 mm) nominal diameter.

2. The regulator is self-contained with no external static or control piping.

3. The regulator has a single port valve with an orifice diameter not greater than that recommended by the manufacturer for the maximum gas pressure at the regulator inlet.

4. The valve seat is made of resilient material designed to withstand abrasion of the gas, impurities in the gas and cutting by the valve, and to resist permanent deformation where it is pressed against the valve port.

5. The regulator is capable, under normal operating conditions, of regulating the downstream pressure within the necessary limits of accuracy and of limiting the discharge pressure under no-flow conditions to not more than 150 percent of the discharge pressure maintained under flow conditions.

Pressure-relieving or pressure-limiting devices shall be one of the following:

1. Spring-loaded relief device.

2. Pilot-loaded back pressure regulator used as a relief valve and designed so that failure of the pilot system or external control piping will cause the regulator relief valve to open.

3. A monitoring regulator installed in series with the service or line pressure regulator.

4. A series regulator installed upstream from the service or line regulator and set to continuously limit the pressure on the inlet of the service or line regulator to the maximum working pressure of the downstream piping system.

5. An automatic shutoff device installed in series with the service or line pressure regulator and set to shut off when the pressure on the downstream piping system reaches the maximum working pressure or some other predetermined pressure less than the maximum working pressure. This device shall be designed so that it will remain closed until manually reset.

6. A liquid seal relief device that can be set to open accurately and consistently at the desired pressure.

The devices shall be installed either as an integral part of the service or line pressure regulator or as separate units. Where separate pressure-relieving or pressure-limiting devices are installed, they shall comply with Sections 416.5.1 through 416.5.6.

Pressure relieving and pressure-limiting devices shall be constructed of materials so that the operation of the devices will not be impaired by corrosion of external parts by the atmosphere or of internal parts by the gas. Pressure-relieving and pressure-limiting devices shall be designed and installed so that they can be operated to determine whether the valve is free. The devices shall also be designed and installed so that they can be tested to determine the pressure at which they will operate and examined for leakage when in the closed position.
External control piping shall be protected from falling objects, excavations and other causes of damage and shall be designed and installed so that damage to any control piping will not render both the regulator and the overpressure protective device inoperative.
Each pressure-relieving or pressure-limiting device shall be set so that the pressure does not exceed a safe level beyond the maximum allowable working pressure for the connected piping and appliances.

Precautions shall be taken to prevent unauthorized operation of any shutoff valve that will make a pressure-relieving valve or pressure-limiting device inoperative. The following are acceptable methods for complying with this provision:

1. The valve shall be locked in the open position. Authorized personnel shall be instructed in the importance of leaving the shutoff valve open and of being present while the shutoff valve is closed so that it can be locked in the open position before leaving the premises.

2. Duplicate relief valves shall be installed, each having adequate capacity to protect the system, and the isolating valves and three-way valves shall be arranged so that only one safety device can be rendered inoperative at a time.

The discharge stacks, vents and outlet parts of all pressure-relieving and pressure-limiting devices shall be located so that gas is safely discharged to the outdoors. Discharge stacks and vents shall be designed to prevent the entry of water, insects and other foreign material that could cause blockage. The discharge stack or vent line shall be at least the same size as the outlet of the pressure-relieving device.
The fittings, pipe and openings located between the system to be protected and the pressure-relieving device shall be sized to prevent hammering of the valve and to prevent impairment of relief capacity.
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