This standard shall provide the minimum requirements for the design and installation of automatic fire sprinkler systems and exposure protection sprinkler systems covered within this standard.
This standard shall not provide requirements for the design or installation of water mist fire protection systems, which are not considered fire sprinkler systems and are addressed by NFPA 750.
This standard is written with the assumption that the sprinkler system shall be designed to protect against a single fire originating within the building.
The purpose of this standard shall be to provide a reasonable degree of protection for life and property from fire through standardization of design, installation, and testing requirements for sprinkler systems, including private fire service mains, based on sound engineering principles, test data, and field experience.
Sprinkler systems and private fire service mains are specialized fire protection systems and shall require design and installation by knowledgeable and experienced personnel.
This standard shall apply to the following:
- Character and adequacy of water supplies
- Sprinklers
- Fittings
- Piping
- Valves
- All materials and accessories, including the installation of private fire service mains
Unless otherwise specified, the provisions of this standard shall not apply to facilities, equipment, structures, or installations that existed or were approved for construction or installation prior to the effective date of the standard. Where specified, the provisions of this standard shall be retroactive.
In those cases where the authority having jurisdiction determines that the existing situation presents an unacceptable degree of risk, the authority having jurisdiction shall be permitted to apply retroactively any portions of this standard deemed appropriate.
The retroactive requirements of this standard shall be permitted to be modified if their application clearly would be impractical in the judgment of the authority having jurisdiction, and only where it is clearly evident that a reasonable degree of safety is provided.
Technical documentation shall be submitted to the authority having jurisdiction to demonstrate equivalency.
The system, method, or device shall be approved for the intended purpose by the authority having jurisdiction.
Metric units of measurement in this standard shall be in accordance with the modernized metric system known as the International System of Units (SI).
Two units (liter and bar), outside of but recognized by SI, are commonly used in international fire protection.
These units with conversion factors shall be used as listed in Table 1.6.1.3.
Table 1.6.1.3 Conversion Factors
| Name of Unit | Unit Symbol | Conversion Factor |
|---|---|---|
| liter | L | 1 gal = 3.785 L |
| millimeter per minute | mm/min | 1 gpm/ft2 = 40.746 mm/min = 40.746 (L/min)/m2 |
| cubic decimeter | dm3 | 1 gal = 3.785 dm3 |
| pascal | Pa | 1 psi = 6894.757 Pa |
| bar | bar | 1 psi = 0.0689 bar |
| bar | bar | 1 bar = 105 Pa |
| Note: For additional conversions and information, see ASTM SI10, Standard for Use of the International System of Units (SI): The Modern Metric System. | ||
The standard abbreviations in Table 1.6.2 shall be used on the hydraulic calculation form discussed in Chapter 23.
Table 1.6.2 Hydraulic Symbols
| Symbol or Abbreviation | Item |
|---|---|
| p | Pressure in psi |
| gpm | U.S. gallons per minute |
| q | Flow increment in gpm to be added at a specific location |
| Q | Summation of flow in gpm at a specific location |
| Pt | Total pressure in psi at a point in a pipe |
| Pf | Pressure loss due to friction between points indicated in location column |
| Pe | Pressure due to elevation difference between indicated points. This can be a plus value or a minus value. If minus, the (—) shall be used; if plus, no sign is needed. |
| Pv | Velocity pressure in psi at a point in a pipe |
| Pn | Normal pressure in psi at a point in a pipe |
| E | 90-degree ell |
| EE | 45-degree ell |
| Lt.E | Long-turn elbow |
| Cr | Cross |
| T | Tee-flow turned 90 degrees |
| GV | Gate valve |
| BV | Butterfly (wafer) check valve |
| Del V | Deluge valve |
| ALV | Alarm valve |
| DPV | Dry pipe valve |
| CV | Swing check valve |
| WCV | Butterfly (wafer) check valve |
| St | Strainer |
| psi | Pounds per square inch |
| v | Velocity of water in pipe in feet per second |
| K | K-factor |
| C-factor | Friction loss coefficient |
Some dimensions used in this standard are exact and some are not. Nominal dimension are often used, such as the dimensions used for pipe sizes. The metric equivalent shown in this standard might not be an exact conversion to the SI unit, but the nominal metric equivalent is typically used or a reasonably equivalent value or approximate conversion is used. It shall be acceptable to use the exact conversion or the conversions stated in the standard, even though they might not be exact.