ASME B31.9 covers “utility piping.” The Code DEFINES and QUANTIFIES the phrase “utility piping.” We use this code for utilities associated with our PSM/RMP-covered processes WHEN the utility either PREVENTS, PROTECTS, or MITIGATES an event. Specifically, the code applies to the following services, except as excluded in para. 900.1.3:
- water and antifreeze solutions for heating and cooling
- condensing water
- steam or other condensate
- other nontoxic liquids
- steam
- vacuum
- compressed air
- other nontoxic, nonflammable gases
- combustible liquids, including fuel oil
The code is also used for “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 (1103 kPa gage) max. and 250°F (121°C) max.
The external piping of the boiler 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.