WAC 296-307-41513. Safety devices for cylinder systems

(1) Containers must have safety devices as required by DOT regulations. (2) A final stage regulator of an LP-gas system (excluding any appliance regulator) must have, on the low-pressure side, a relief valve that is set to start to discharge within the limits specified in Table U-7. TABLE U-7 Relief valve start-to-discharge pressure setting (percent of regulator delivery pressure) Regulator delivery pressure Minimum Maximum 1 psig or less 200 300 Above 1 psig but not over 3 psig 140 200 Above 3 psig 125 200 Relief valve start-to-discharge pressure setting (percent of regulator delivery pressure) Regulator delivery pressure Minimum Maximum 1 psig or less 200 300 Above 1 psig but not over 3 psig 140 200 Above 3 psig 125 200 (3) When a regulator or pressure relief valve is used indoors for other than purposes specified in WAC 296-307-41017 (1), the relief valve and the space above the regulator and relief valve diaphragms must be vented to the outside air with the discharge outlet located at least three feet horizontally away from any building opening that is below such discharge. Exception: This requirement does not apply to individual appliance regulators when protection is otherwise provided, nor to WAC 296-307-41509 and 296-307-41025 (14). In buildings devoted exclusively to gas distribution, the space above the diaphragm need not be vented to the outside.