scope:

Coverage and Application.

This Code Section has rules for the piping in industrial, institutional, commercial, and public buildings, and in multi-unit residences, which does not require the range of sizes, pressures, and temperatures covered in ASME B31.1. This Code prescribes requirements for the design, materials, fabrication, installation, inspection, examination, and testing of piping systems for building services. It includes piping systems in the building or within the property limits.

Services and Limits

(a) Services. This Code applies to the following building services, except as excluded in para. 900.1.3:

(1) water and antifreeze solutions for heating and cooling

(2) condensing water

(3) steam or other condensate

(4) other nontoxic liquids

(5) steam

(6) vacuum

(7) compressed air

(8) other nontoxic, nonflammable gases

(9) combustible liquids including fuel oil

(b) Boiler External Piping. The scope of this Code includes boiler external piping within the following limits:

(1) for steam boilers, 15 psig (103 kPa gage) max.

(2) for water heating units, 160 psig (1 103 kPa gage) max. and 250°F (121°C) max.

Boiler external piping above these pressure or temperature limits is within the scope of ASME B31.1. Boiler external piping is the piping connected to the boiler and extending to the points identified in Figure 900.1.2.

(c) Material and Size Limits. Piping systems of the following materials are within the scope of this Code, through the indicated maximum size (and wall thickness if noted):

(1) carbon steel: NPS 48 (DN 1200) and 0.50 in. (12.7 mm) wall

(2) stainless steel: NPS 24 (DN 600) and 0.50 in. (12.7 mm) wall

(3) aluminum: NPS 12 (DN 300)

(4) brass and copper: NPS 12 (DN 300) and 12.125 in. (308 mm) O.D. for copper tubing

(5) thermoplastics: NPS 24 (DN 600)

(6) ductile iron: NPS 48 (DN 1200)

(7) reinforced thermosetting resin (RTR): 24 in. (600 mm) nominal Other materials may be used as noted in Chapter III.

(d) Pressure Limits. Piping systems with working pressures not in excess of the following limits are within the scope of this Code:

(1) steam and condensate: 150 psig (1 034 kPa gage)

(2) liquids: 350 psig (2 413 kPa gage)

(3) vacuum: 1 atm external pressure

(4) compressed air and gas: 150 psig (1 034 kPa gage)

(e) Temperature Limits. Piping systems with working temperatures not in excess of the following limits are within the scope of this Code:

(1) steam and condensate: 366°F (186°C)

(2) other gases and vapors: 200°F (93°C)

(3) other nonflammable liquids: 250°F (121°C) The minimum temperature for all services is 0°F (−18°C).

Exclusions.

This Code does not apply to economizers, heaters, pumps, tanks, heat exchangers, and equipment covered by the ASME Boiler and Pressure Vessel Code (BPVC).

Units of Measure.

This Code states values in both USC and SI units. Within the text, the SI units are shown in parentheses. The values stated in each system are not exact equivalents; therefore, each system of units should be used independently of the other.

When separate equations are provided for USC and SI units, those equations shall be executed using variables in the units associated with the specific equation. The results obtained from execution of these equations may be converted to other units.

When necessary to convert from one system of units to another, conversion should be made by rounding the values to the number of significant digits of implied precision in the starting value, but not less than four significant digits for use in calculations.