In addition to NFPA 58, §5.2.4.2 and 5.9.2.5(A), 200 psig working pressure stationary vessels in LP-gas service in Texas prior to September 1, 1981, may be continued in service for commercial propane provided that they are fitted with pressure relief valves set for 250 psig normal start to discharge and comply with other provisions of this chapter. For the purpose of this section, "commercial propane" is defined as having a vapor pressure not in excess of 210 psig at 100 degrees Fahrenheit. This section does not apply to LP-gas motor fuel and mobile fuel containers.
16 Tex. Admin. Code § 9.131