Washington Administrative Code › Title 296 - Labor and Industries, Department of › Chapter 296-24 - General safety and health standards › Part K - COMPRESSED GAS AND COMPRESSED GAS EQUIPMENT › Section 296-24-93503 - General requirements

Current through Register Vol. 24-14, July 15, 2024
(1)
Application.
See WAC
				296-24-93003(1).
(2)
Specifications and tests.
All safety relief devices covered by these standards must meet the design,
				construction, marking, and test specifications of the "Compressed Gas
				Association Safety Relief Device Standards Part 2-Cargo and Portable Tanks for
				Compressed Gases: S-1.2-1963."
(3)
Specific requirements for safety relief devices.
(a) You must provide each container with one
				or more safety relief devices which, unless otherwise specified, must be safety
				relief valves of the spring-loaded type.
(b) You must set safety relief valves to
				start-to-discharge at a pressure not in excess of 110 % of the DOT design
				pressure of the container nor less than the DOT design pressure of the
				container except as follows:
(i) If an
				overdesigned container is used, the set pressure of the safety relief valve may
				be between the minimum required DOT design pressure for the lading and 110 % of
				the DOT design pressure of the container used.
(ii) For sulfur dioxide containers, a minimum
				set pressure of 120 and 110 p.s.i.g. is permitted for the 150 and 125 p.s.i.g.
				DOT design pressure containers, respectively.
(iii) For carbon dioxide (refrigerated),
				nitrous oxide (refrigerated), and pressurized liquid argon, nitrogen and
				oxygen, there must be no minimum set pressure.
(iv) For butadiene, inhibited, and liquefied
				petroleum gas containers, a minimum set pressure of 90 % of the minimum design
				pressure permitted for these ladings may be used.
(v) For containers constructed in accord with
				paragraph U-68 or U-69 of the Code 1949 Edition, the set pressure marked on the
				safety relief valve may be 125 % of the original DOT design pressure of the
				container.
(c) You must
				only use replacement parts or assemblies provided by the manufacturer of the
				device unless the suitability of interchange is proved by adequate
				tests.
(d) Safety relief valves
				must have direct communication with the vapor space of the container.
(e) Any portion of liquid piping or hose
				which at any time may be closed at each end must be provided with a safety
				relief device to prevent excessive pressure.
(f) The additional restrictions of this
				subdivision apply to safety relief devices on containers for carbon dioxide or
				nitrous oxide which are shipped in refrigerated and insulated containers. The
				maximum operating pressure in the container may be regulated by the use of one
				or more pressure controlling devices, which devices must not be in lieu of the
				safety relief valve required in WAC
				296-24-93503(3)(a).
(g) You must install and locate all safety
				relief devices so that the cooling effect of the contents will not prevent the
				effective operation of the device.
(h) In addition to the safety relief valves
				required by WAC
				296-24-93503(3)(a)
				 each container for carbon dioxide may be equipped with one or more frangible
				disc safety relief devices of suitable design set to function at a pressure not
				exceeding two times the DOT design pressure of the container.
(i) Subject to conditions of
				49 C.F.R.
				173.315(a)(1) (DOT
				regulations) for methyl chloride and sulfur dioxide optional portable tanks of
				225 p.s.i.g. minimum DOT design pressure, one or more fusible plugs approved by
				the Bureau of Explosives, 50 "F" Street Northwest, Washington, D.C. 20001, may
				be used in lieu of safety relief valves of the spring-loaded type. If the
				container is over 30 inches long a safety relief device having the total
				required flow capacity must be at both ends.
(j) When storage containers for liquefied
				petroleum gas are permitted to be shipped in accordance with
				49 C.F.R.
				173.315(j) (DOT
				regulations), they must be equipped with safety relief devices in compliance
				with the requirements for safety relief devices on above-ground containers as
				specified in the National Fire Protection Association Pamphlet No. 58-1969
				"Standard for the Storage and Handling of Liquefied Petroleum Gases."
(k) When containers are filled by pumping
				equipment which has a discharge capacity in excess of the capacity of the
				container safety relief devices, and which is capable of producing pressures in
				excess of DOT design pressure of the container, precautions should be taken to
				prevent the development of pressures in the container in excess of 120 % of its
				DOT design pressure. This may be done by providing additional capacity of the
				safety relief valves on the container, by providing a bypass on the pump
				discharge, or by any other suitable method.
(l) This additional requirement applies to
				safety relief devices on containers for liquefied hydrogen and pressurized
				liquid argon, nitrogen, and oxygen. You must protect the liquid container by
				one or more safety relief valves and one or more frangible discs.
(m) You must arrange safety relief devices to
				discharge unobstructed to the open air in such a manner as to prevent any
				impingement of escaping gas upon the container. You must arrange safety relief
				devices to discharge upward except this is not required for carbon dioxide,
				nitrous oxide and pressurized liquid argon, nitrogen, and oxygen.
(n) You must not install any shutoff valves
				between the safety relief devices and the container except, in cases where two
				or more safety relief devices are installed on the same container, a shutoff
				valve may be used where the arrangement of the shutoff valve or valves is such
				as always to insure full required capacity flow through at least one safety
				relief device.