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 deliveryto 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 pipinglocated within buildings shall be installed in accordance with the structural safety and fire protection provisions of the International Building Code.
Where an additional applianceis 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 pipingof adequate capacity shall be provided.
For other than steel pipe, exposed pipingshall 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 applianceserved.
Where two or more meters are installed on the same premises but supply separate consumers, the piping systems shall not be interconnected on the outletside of the meters.
Pipingfrom multiple meter installations shall be marked with an approvedpermanent identification by the installer so that the piping system supplied by each meter is readily identifiable.
Pipe utilized for the installation, extension and alterationof 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, tubing and fittings shall comply with the applicable referenced standards, specifications and performance criteria of this code and shall be identified in accordance with Section 401.9. Piping, tubing and fittings shall either be tested by an approved third-party testing agency or certified by an approved thirdparty certification agency.
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 applianceinlet at not less than the minimum supply pressure required by the appliance.
The volumetric flow rate of gas to be provided shall be the sum of the maximum input of the appliances served.
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.
The volumetric flow rate of gas to be provided shall be adjusted for altitude where the installation is above 2,000 feet (610 m) in elevation.
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.
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:
NA means a flow of less than 10 cfh.
All table entries have been rounded to three significant digits.
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:
NA means a flow of less than 10 cfh.
All table entries have been rounded to three significant digits.
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.
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.
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.
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.
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.
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:
Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.
NA means a flow of less than 10 cfh.
All table entries have been rounded to three significant digits.
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:
Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.
NA means a flow of less than 10 cfh.
All table entries have been rounded to three significant digits.
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:
Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.
NA means a flow of less than 10 cfh.
All table entries have been rounded to three significant digits.
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:
Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.
All table entries have been rounded to three significant digits.
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:
Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.
All table entries have been rounded to three significant digits.
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:
Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.
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:
Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.
All table entries have been rounded to three significant digits.
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:
Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends 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 or bends.
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.
All table entries have been rounded to three significant digits.
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:
Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends 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 or bends.
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.
All table entries have been rounded to three significant digits.
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:
Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends 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 or bends.
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.
All table entries have been rounded to three significant digits.
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.
CAUTION: Capacities shown in the table might exceed maximum capacity for a selected regulator. Consult with the regulator or tubing manufacturer for guidance.
Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends 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 or bends.
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.
All table entries have been rounded to three significant digits.
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.
CAUTION: Capacities shown in the table might exceed maximum capacity for a selected regulator. Consult with the regulator or tubing manufacturer for guidance.
Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends 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 or bends.
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.
All table entries have been rounded to three significant digits.
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.
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.
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.
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:
NA means a flow of less than 10 cfh.
All table entries have been rounded to three significant digits.
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:
NA means a flow of less than 10 cfh.
All table entries have been rounded to three significant digits.
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.
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.
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.
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.
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:
Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.
All table entries have been rounded to three significant digits.
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:
Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.
NA means a flow of less than 10,000 Btu/hr.
All table entries have been rounded to three significant digits.
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:
Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.
All table entries have been rounded to three significant digits.
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:
Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends 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 or bends.
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.
All table entries have been rounded to three significant digits.
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 = 6.895kPa, 1-inch water column = 0.2488 kPa, 1 British thermal unit per hour = 0.293 1 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.01745 rad.
CAUTION: Capacities shown in the table might exceed maximum capacity for a selected regulator. Consult with the regulator or tubing manufacturer for guidance.
Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends 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 or bends.
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.
All table entries have been rounded to three significant digits.
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.
CAUTION: Capacities shown in the table might exceed maximum capacity of selected regulator. Consult with the tubing manufacturer for guidance.
Table includes losses for four 90-degree bends and two end fittings. Tubing runs with larger numbers of bends 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 or bends.
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.
All table entries have been rounded to three significant digits.
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.
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.
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 = 0.293 1 W, 1 cubic foot per hour = 0.0283 m3/h, 1 degree = 0.0 1745 rad.
Note: All table entries have been rounded to three significant digits.
The pipe size of each section of gas pipingshall be determined using the longest length of pipingfrom the point of deliveryto the most remote outletand the load of the section.
Pipe size of each section of the longest pipe run from the point of deliveryto the most remote outletshall be determined using the longest run of pipingand the load of the section.
The pipe size of each section of branch pipingnot previously sized shall be determined using the length of pipingfrom the point of deliveryto the most remote outletin each branch and the load of the section.
The design pressure loss in any piping system under maximum probable flow conditions, from the point of deliveryto the inlet connection of the appliance, shall be such that the supply pressure at the applianceis 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:
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.
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 approvedby the code official.
Copper and copper alloy 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, copper alloy 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. Aluminum-alloy pipe 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.
Copper tubing shall comply with Standard Type K or L of ASTM B 88 or ASTM B 280.
Copper and copper alloy 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. Aluminumalloy 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.
Polyethylene plastic pipe, tubing and fittings used to supply fuel gas shall conform to ASTM D 2513. Such pipe shall be marked "Gas" and "ASTM D 2513."
Plastic pipe, tubing and fittings, other than polyethylene, shall be identified and conform to the 2008 edition of ASTM D 2513. Such pipe shall be marked "Gas" and "ASTM D 2513."
Polyvinyl chloride (PVC) and chlorinated polyvinyl chloride (CPVC) plastic pipe, tubing and fittings shall not be used to supply fuel gas.
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.
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).
Plastic pipe and fittings used to connect regulatorvents to remote vent terminations shall be PVC conforming to ANSI/UL 651. PVC ventpipingshall 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.
Where in contact with material or atmosphere exerting a corrosive action, metallic pipingand fittings coated with a corrosion-resistant material shall be used. External or internal coatings or linings used on pipingor components shall not be considered as adding strength.
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.
Thread joint compounds 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 pipingjoint 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 approvedgas 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:
Threaded fittings in sizes larger than 4 inches (102 mm) shall not be used.
Fittings used with steel or wrought-iron pipe shall be steel, copper alloy, malleable iron or cast iron.
Fittings used with copper or copper alloy pipe shall be copper or copper alloy.
Fittings used with aluminum-alloy pipe shall be of aluminum alloy.
Cast-iron fittings:
Flanges shall be permitted.
Bushings shall not be used.
Fittings shall not be used in systems containing flammable gas-air mixtures.
Fittings in sizes 4 inches (102 mm) and larger shall not be used indoors except where approved.
Fittings in sizes 6 inches (152 mm) and larger shall not be used except where approved.
Aluminum-alloy fittings. Threads shall not form the joint seal.
Zinc aluminum-alloy fittings. Fittings shall not be used in systems containing flammable gas-air mixtures.
Special fittings. Fittings such as couplings, proprietary-type joints, saddle tees, gland-type compression fittings and flared, flareless and 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 and contraction; and shall be approved.
Where pipe fittings are drilled and tapped in the field, the operation shall be in accordance with all of the following:
The operation shall be performed on systems having operating pressures of 5 psi (34.5 kPa) or less.
The operation shall be performed by the gas supplier or the gas supplier's designated representative.
The drilling and tapping operation shall be performed in accordance with written procedures prepared by the gas supplier.
The fittings shall be located outdoors.
The tapped fitting assembly shall be inspected and proven to be free of leakage.
Plastic pipe, tubing and fittings shall be joined in accordance with the manufacturer's instructions. Such joint shall comply with the following:
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 pipingmaterial.
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."
Where compression-type mechanical joints are used, the gasket material in the fitting shall be compatible with the plastic pipingand 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.
Plastic pipingjoints and fittings for use in liquefied petroleum gas piping systems shall be in accordance with NFPA 58.
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.
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 (plain or corrugated), composition, aluminum "O" rings, spiral wound metal gaskets, rubber-faced phenolic and elastomeric. Where a flanged joint is opened, the gasket shall be replaced. Full-face flange gaskets shall be used with all nonsteel flanges.
Materials used shall be installed in strict accordance with the standards under which the materials are accepted and approved. In the absence of such installation procedures, the manufacturer's instructions shall be followed. Where the requirements of referenced standards or manufacturer's instructions do not conform to minimum provisions of this code, the provisions of this code shall apply.
CSST piping systems shall be installed in accordance with the terms of their approval, the conditions of listing, the manufacturer's instructions and this code.
Pipingshall not be installed in or through a ducted supply, return or exhaust, or a clothes chute, chimney or gas vent, dumbwaiter or elevator shaft. Pipinginstalled downstream of the point of deliveryshall not extend through any townhouse unit other than the unit served by such piping.
Gas pipingshall not penetrate building foundation walls at any point below grade. Gas pipingshall enter and exit a building at a point above grade and the annular space between the pipe and the wall shall be sealed.
Where pipingwill be concealed within light-frame construction assemblies, the pipingshall be protected against penetration by fasteners in accordance with Sections 404.7.1 through 404.7.3.
Exception: Black steel piping and galvanized steel piping shall not be required to be protected.
Where pipingis installed through holes or notches in framing members and the pipingis located less than 11/2 inches (38 mm) from the framing member face to which wall, ceiling or floor membranes will be attached, the pipe shall be protected by shield plates that cover the width of the pipe and the framing member and that extend not less than 4 inches (102 mm) to each side of the framing member. Where the framing member that the pipingpasses through is a bottom plate, bottom track, top plate or top track, the shield plates shall cover the framing member and extend not less than 4 inches (102 mm) above the bottom framing member and not less than 4 inches (102 mm) below the top framing member.
Where the piping is located within a framing member and is less than 11/2 inches (38 mm) from the framing member face to which wall, ceiling or floor membranes will be attached, the piping shall be protected by shield plates that cover the width and length of the piping. Where the piping is located outside of a framing member and is located less than 11/2 inches (38 mm) from the nearest edge of the face of the framing member to which the membrane will be attached, the piping shall be protected by shield plates that cover the width and length of the piping.
Pipingin solid floors shall be laid in channels in the floor and covered in a manner that will allow access to the pipingwith a minimum amount of damage to the building. Where such pipingis subject to exposure to excessive moisture or corrosive substances, the pipingshall be protected in an approvedmanner. As an alternative to installation in channels, the pipingshall be installed in a conduit of Schedule 40 steel, wrought iron, PVC or ABS pipe in accordance with Section 404.8.1 or 404.8.2.
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 pipingshall 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 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.
Piping installed outdoors shall be elevated not less than 31/2 inches (89 mm) above ground and where installed across roof surfaces, shall be elevated not less than 31/2 inches (89 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 be protected against corrosion by coating or wrapping with an inert material. Wherepiping is encased in a protective pipe sleeve, the annular space between thepiping and the sleeve shall be sealed.
Fuel gas services shall be in an approved location and/or provided with structures designed to protect the fuel gasmeter and surrounding piping from physical damage, including falling, moving, or migrating ice and snow. If an added structure is used, it must still provide access for service and comply with the IBC or the IRC.
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 socketwelded joints shall not be used in pipingin contact with soil or where internal or external crevice corrosion is known to occur.
Pipe protective coatings and wrappings shall be approvedfor the application and shall be factory applied.
Exception: Where installed in accordance with the manufacturer's 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.
Individual lines to outdoor lights, grills and other appliances shall be installed not less than 8 inches (203 mm) below finished grade, provided that such installation is approvedand is installed in locations not susceptible to physical damage.
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 404.11 and shall be installed in accordance with Section 404.14.1 or 404.14.2.
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 outletsthat do not connect to appliances shall be capped gas tight.
Exception: Listed and labeledflush-mounted-type quickdisconnect devices and listed and labeledgas convenience outlets shall be installed in accordance with the manufacturer's instructions.
The unthreaded portion of pipingoutletsshall extend not less than l inch (25 mm) through finished ceilings and walls and where extending through floors or outdoor patios and slabs, shall be not less than 2 inches (51 mm) above them. The outlet fitting or pipingshall be securely supported. Outletsshall not be placed behind doors. Outletsshall be located in the room or space where the applianceis installed.
Exception: Listed and labeledflush-mounted-type quick-disconnect devices and listed and labeledgas convenience outletsshall be installed in accordance with the manufacturer's instructions.
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:
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 instructions.
Plastic pipe shall be permitted to terminate with a wall head adapter within buildings where the plastic pipe is inserted in a pipingmaterial for fuel gas use in buildings.
Plastic pipe shall be permitted under outdoor patio, walkway and driveway slabs provided that the burial depth complies with Section 404.12.
Connections made outdoors and underground between metallic and plastic pipingshall be made only with transition fittings conforming to ASTM D 2513 Category I or ASTM F 1973.
A yellow insulated copper tracer wire or other approvedconductor shall be installed adjacent to underground nonmetallic piping. Accessshall 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 be not less than 18 AWG and the insulation type shall be suitable for direct burial.
Before any system of pipingis 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.
Factory-made welding elbows or transverse segments cut therefrom shall have an arc length measured along the crotch of not less than 1 inch (25 mm) in pipe sizes 2 inches (51 mm) and larger.
Prior to acceptance and initial operation, all pipinginstallations shall be visually inspected and pressure tested to determine that the materials, design, fabrication and installation practices comply with the requirements of this code.
In the event repairs or additions are made after the pressure test, the affected pipingshall 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 approvedleak-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 pipingand the existing pipingshall be tested with a noncorrosive leak-detecting fluid or other approved leakdetecting 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, except where a double block and bleed valve system is installed. 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.
Appliances and equipmentthat are not to be included in the test shall be either disconnected from the pipingor isolated by blanks, blind flanges or caps. Flanged joints at which blinds are inserted to blank off other equipmentduring the test shall not be required to be tested.
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 not 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 singlefamily 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.
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.
Where existing gas piping is opened, the section that is opened shall be isolated from the gas supply and the line pressure vented in accordance with Section 406.7.1.3. Where gas pipingmeeting the criteria of Table 406.7.1.1 is removed from service, the residual fuel gas in the pipingshall be displaced with an inert gas.
Where gas pipingcontaining air and meeting the criteria of Table 406.7.1.1 is placed in operation, the air in the pipingshall first be displaced with an inert gas. The inert gas shall then be displaced with fuel gas in accordance with Section 406.7.1.3.
The open end of a piping system being pressure vented or purged shall discharge directly to an outdoor location. Purging operations shall comply with all of the following requirements:
The point of discharge shall be controlled with a shutoff valve.
The point of discharge shall be located not less than 10 feet (3048 mm) from sources of ignition, not less than 10 feet (3048 mm) from building openings and not less than 25 feet (7620 mm) from mechanical air intake openings.
During discharge, the open point of discharge shall be continuously attended and monitored with a combustible gas indicator that complies with Section 406.7.1.4.
Purging operations introducing fuel gas shall be stopped when 90 percent fuel gas by volume is detected within the pipe.
Persons not involved in the purging operations shall be evacuated from all areas within 10 feet (3048 mm) of the point of discharge.
Combustible gas indicators shall be listed and shall be calibrated in accordance with the manufacturer's instructions. Combustible gas indicators shall numerically display a volume scale from zero percent to 100 percent in 1 percent or smaller increments.
The piping system shall be purged in accordance with one or more of the following:
The piping shall be purged with fuel gas and shall discharge to the outdoors.
The piping shall be purged with fuel gas and shall discharge to the indoors or outdoors through an applianceburner not located in a combustion chamber. Such burner shall be provided with a continuous source of ignition.
The piping shall be purged with fuel gas and shall discharge to the indoors or outdoors through a burner that has a continuous source of ignition and that is designed for such purpose.
The piping shall be purged with fuel gas that is discharged to the indoors or outdoors, and the point of discharge shall be monitored with a listed combustible gas detector in accordance with Section 406.7.2.2. Purging shall be stopped when fuel gas is detected.
The pipingshall be purged by the gas supplier in accordance with written procedures.
Combustible gas detectors shall be listed and shall be calibrated or tested in accordance with the manufacturer's instructions. Combustible gas detectors shall be capable of indicating the presence of fuel gas.
Pipingshall 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. Pipingshall 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 pipingbetween anchors. All parts of the supporting equipmentshall be designed and installed so that they will not be disengaged by movement of the supported piping.
Where wet gas exists, a drip shall be provided at any point in the line of pipe where condensate could collect. A drip shall 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.
Where a sediment trap is not incorporated as part of the appliance, a sediment trap shall be installed downstream of the appliance shutoffvalve 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 as illustrated in Figure 408.4 or other device approved as an effective sediment trap. Illuminating appliances, ranges, clothes dryers, decorative vented appliances for installation in vented fireplaces, gas fireplaces and outdoor grills need not be so equipped.
FIGURE 408.4 Method of Installing a tee fitting sediment trap
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.
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.
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.
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 shutoffvalves located in the firebox of a fireplaceshall be installed in accordance with the appliancemanufacturer's instructions.
Where provided with two or more fuel gasoutlets, 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."
The MP regulator shall be approvedand shall be suitable for the inlet and outlet gas pressures for the application.
The MP regulator shall maintain a reduced outlet pressure under lock-up (no-flow) conditions.
The capacity of the MP regulator, determined by published ratings of its manufacturer, shall be adequate to supply the appliancesserved.
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 leaklimiting device, in either case complying with Section 410.3.
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.
A tee fitting with one opening capped or plugged shall be installed not less than 10 pipe diameters downstream of the MP regulatoroutlet. Such tee fitting shall be positioned to allow connection of a pressure-measuring instrument.
Where connected to rigid piping, a union shall be installed within 1 foot (304 mm) of either side of the MP regulator.
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 labeledfor utilization with an approvedvent-limiting device installed in accordance with the manufacturer's instructions.
Ventpipingfor reliefvents and breathervents shall be constructed of materials allowed for gas pipingin accordance with Section 403. Ventpiping shall be not smaller than the vent connection on the pressure-regulating device. Ventpipingserving reliefvents and combination relief and breathervents shall be run independently to the outdoors and shall serve only a single device vent. Ventpipingserving only breathervents is permitted to be connected in a manifold arrangement where sized in accordance with an approveddesign that minimizes backpressure in the event of diaphragm rupture. Regulatorventpipingshall not exceed the length specified in the regulator manufacturer's instructions.
Where automaticexcess flow valvesare installed, they shall be listed for the application and shall be sized and installed in accordance with the manufacturer's instructions.
Where fuel gas is used with oxygen in any hot work operation, a listed protective device that serves as a combination flashback arrestor and backflow check valve shall be installed at an approved location on both the fuel gas and oxygen supply lines. Where the pressure of the piped fuel gas supply is insufficient to ensure such safe operation, approvedequipment shall be installed between the gas meter and the appliance that increases pressure to the level required for such safe operation.
Corrugated stainless steel tubing (CSST) where installed in accordance with the manufacturer's instructions.
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.
Listed and labeledapplianceconnectors in compliance with ANSI Z21.24 and installed in accordance with the manufacturer's instructions and located entirely in the same room as the appliance.
Listed and labeledoutdoor appliance connectors in compliance with ANSI Z21.75/CSA 6.27 and installed in accordance with the manufacturer's 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. The commercial cooking appliance connector installation shall be configured in accordance with the manufacturer's instructions. Movement of appliances with casters shall be limited by a restraining device installed in accordance with the connector and appliance manufacturer's instructions.
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.
Connectors shall not be concealed within, or extended through, walls, floors, partitions, ceilings or appliancehousings.
Exceptions:
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.
Rigid steel pipe connectors shall be permitted to extend through openings in appliancehousings.
Fireplaceinserts that are factory equipped with grommets, sleeves or other means of protection in accordance with the listing of the appliance.
Semirigid tubing and listed connectors shall be permitted to extend through an opening in an appliancehousing, cabinet or casing where the tubing or connector is protected against damage.
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 pipingby means of an appliance connector listed as complying with ANSI Z21.69 or by means of Item 1 of Section 411.1. Such flexible connectors shall be installed and protected against physical damage in accordance with the manufacturer's instructions.
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.
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
Motor vehicle fueling operations shall be conducted by qualified attendants or in accordance with Section 412.9 by persons trained in the proper handling of LP-gas.
The point of transfer for LP-gas dispensing operations shall be separated from buildings and other exposures in accordance with the following:
Not less than 25 feet (7620 mm) from buildings where the exterior wall is not part of a fire-resistance-rated assembly having a rating of 1 hour or greater.
Not less than 25 feet (7620 mm) from combustible overhangs on buildings, measured from a vertical line dropped from the face of the overhang at a point nearest the point of transfer.
Not less than 25 feet (7620 mm) from the lot line of property that can be built upon.
Not less than 25 feet (7620 mm) from the centerline of the nearest mainline railroad track.
Not less than 10 feet (3048 mm) from public streets, highways, thoroughfares, sidewalks and driveways.
Not less than 10 feet (3048 mm) from buildings where the exterior wall is part of a fire-resistance-rated assembly having a rating of 1 hour or greater.
Exception:
The point of transfer for LP-gas dispensing operations need not be separated from canopies that are constructed in accordance with the International Building Codeand that provide weather protection for the dispensing equipment.
Liquefied petroleum gas containers shall be located in accordance with the International Fire Code. Liquefied petroleum gas storage and dispensing equipmentshall be located outdoors and in accordance with the International Fire Code.
LP-gas dispensers and related equipment shall comply with the following provisions:
Pumps shall be fixed in place and shall be designed to allow control of the flow and to prevent leakage and accidental discharge.
Dispensing devices installed within 10 feet (3048 mm) of where vehicle traffic occurs shall be protected against physical damage by mounting on a concrete island 6 inches (152 mm) or more in height, or shall be protected in accordance with Section 312 of the International Fire Code.
Dispensing devices shall be securely fastened to their mounting surface in accordance with the dispenser manufacturer's instructions.
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.
The dispenser system piping shall be protected from uncontrolled discharge in accordance with the following:
Where mounted on a concrete base, a means shall be provided and installed within 1/2 inch (12.7 mm) of the top of the concrete base that will prevent flow from the supply piping in the event that the dispenser is displaced from its mounting.
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 where the dispenser hose is connected to the liquid piping.
A listed automatic-closing-type hose nozzle valve with or without a latch-open device shall be provided on island-type dispensers.
Hoses and pipingfor the dispensing of LP-gas shall be provided with hydrostatic relief valves. The hose length shall not exceed 18 feet (5486 mm). An approvedmethod shall be provided to protect the hose against mechanical damage.
Where installed within 10 feet (3048 mm) of vehicle traffic, LP-gas storage containers, pumps and dispensers shall be protected in accordance with Section 2307.5, Item 2 of the International Fire Code.
Dispenser hoses shall be equipped with a listed emergency breakaway device designed to retain liquid on both sides of the breakaway point. Where hoses are attached to hose-retrieving mechanisms, the emergency breakaway device shall be located such that the breakaway device activates to protect the dispenser from displacement.
Self-service LP-gas dispensing systems, including key, code and card lock dispensing systems, shall be limited to the filling of permanently mounted containers providing fuel to the LP-gas-powered vehicle.
The requirements for self-service LP-gas dispensing systems shall be in accordance with the following:
The arrangement and operation of the transfer of product into a vehicle shall be in accordance with this section and Chapter 61 of the International Fire Code.
The system 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.
The owner of the LP-gas motor fuel-dispensing facility or the owner's designee shall provide for the safe operation of the system and the training of users.
The dispenser and hose-end valve shall release not more than 4 cubic centimeters of liquid to the atmosphere upon breaking of the connection with the fill valve on the vehicle.
Fire extinguishers shall be provided in accordance with Section 2305.4 of the International Fire Code.
Warning signs shall be provided in accordance with Section 2305.6 of the International Fire Code.
The area around the dispenser shall be maintained in accordance with Section 2305.7 of the International Fire Code.
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 equipmentused for the storage, compression or dispensing of CNG shall be approvedor listed in accordance with Sections 413.2.1 through 413.2.3.
Hoses, hose connections, dispensers, gas detection systems and electrical equipmentused 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 applianceshall not exceed 5 standard cubic feet per minute (0.14 standard cubic meter/min) of natural gas.
Compression, storage and dispensing equipmentshall be located above ground outside.
Exceptions:
Compression, storage or dispensing equipmentis 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.
Compression, storage and dispensing equipmentis allowed to be located indoors or in vaults in accordance with the International Fire Code.
In addition to the fuel-dispensing requirements of the International Fire Code, compression, storage and dispensing equipmentnot located in vaults complying with the International Fire Code and other than residential fueling appliances shall not be installed:
Less than 10 feet (3048 mm) from the nearest building or property that could be built on, public street, sidewalk or source of ignition.
Exception: Dispensing equipmentneed not be separated from canopies that provide weather protection for the dispensing equipmentand are constructed in accordance with the International Building Code.
Less than 25 feet (7620 mm) from the nearest rail of any railroad track.
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.
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 connected to the premises' gas piping system without causing damage to the piping system or the connection to the internal applianceapparatus.
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 applianceand 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.
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 approvedmethod of atmospheric venting in accordance with Section 413.9.1 or 413.9.2.
A documented procedure that 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 equipmentsettings shall be provided to the code official for review and approval. The drawing shall illustrate the pipingand regulator arrangement and shall be shown in spatial relation to the location of the compressor, storage vessels and emergency shutdown devices.
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 horizontal and lateral movement of the vessel. The system shall be designed to prevent movement of the vessel based on the highest gas-release velocity through valveorifices 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
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 approvedfor use with CNG in accordance with the International Fire Code.
The vent tube shall be capable of dispersing the gas not less than 10 feet (3048 mm) above grade level. The vent tube shall not be provided with a rain cap or other feature that 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. ApprovedCYLINDER 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.
Where the serving gas supplier delivers gas at a pressure greater than 2 psi for piping systems serving appliances designed to operate at a gas pressure of 14 inches w.c. or less, overpressure protection devices shall be installed. Piping systems serving equipment designed to operate at inlet pressures greater than 14 inches w.c. shall be equipped with overpressure protection devices as required by the appliance manufacturer's installation instructions.
Where piping systems serving appliances designed to operate with a gas supply pressure of 14 inches w.c. or less are required to be equipped with overpressure protection by Section 416.1, each overpressure protection device shall be adjusted to limit the gas pressure to each connected appliance to 2 psi or less upon a failure of the line pressure regulator.
Where piping systems serving appliances designed to operate with a gas supply pressure greater than 14 inches w.c. are required to be equipped with overpressure protection by Section 416.1, each overpressure protection device shall be adjusted to limit the gas pressure to each connected appliance as required by the appliance manufacturer's installation instructions.
Each overpressure protection device installed to meet the requirements of this section shall be capable of limiting the pressure to its connected appliance(s) as required by this Section 416.2.1, independently of any other pressure controlequipment in the piping system.
Each gas piping system for which an overpressure protection device is required by Section 416 shall be designed and installed so that a failure of the primary pressure control device(s) is detectable.
Where a pressure relief valve is used to meet the requirements of Section 416, it shall have a flow capacity such that the pressure in the protected system is maintained at or below the limits specified in Section 416.2.1 under all of the following conditions:
The gas pressure at the inlet of the line pressure regulator for which the relief valve is providing overpressure protection is not less than the regulator's normal operating inlet pressure.
