Michigan Administrative Code › Department - Licensing and Regulatory Affairs › Bureau of Fire Services › Storage and Handling of Gaseous and Liquefied Hydrogen Systems › Part 2 - STORAGE AND HANDLING OF GASEOUS HYDROGEN NFPA 50A › Chapter 2 - Design of Gaseous Hydrogen Systems › Section R. 29.7021 - Pressure relief devices

Current through Vol. 24-12, July 15, 2024
Rule 21. Section 2-2.3 is reproduced from NFPA 50A, and
						sections 2-2, 2-2.1, 2-2.2, and 2-2.4 to 2-2.7.1 of the storage and handling of
						gaseous and Liquefied H2 code are added as
						follows:
2-2 Pressure relief devices.
2-2.1 H2 containers shall be
						protected from credible overpressure scenarios by a relief device installed in
						accordance with the ASME International, "Boiler Pressure Vessel Code," section
						VIII division 1 sections UG 125 through 137, adopted by reference in section
						8-1. When all credible overpressure sources are external to the container, the
						relief device(s) need not be installed directly on the container. In such
						cases, the relief devices may be installed in the piping between the container
						and the source(s) of overpressure and a block valve may be installed between
						the relief device(s) and container, provided the source of overpressure is
						blocked from the container.
2-2.1.1 Fully over-wrapped carbon composite containers
						shall be protected by thermally activated pressure relief devices acceptable to
						the department based on the best interests of public health, safety, welfare
						and the environment.
2-2.2 Pressure relief devices, when installed, shall be
						arranged to discharge upward and unobstructed to the open air in such a manner
						as to prevent any impingement of escaping gas upon the container, adjacent
						structures, or personnel. The vent and piping system from relief device(s)
						shall be designed and installed in accordance with CGA G-5.5.
2-2.3 Pressure relief devices or vent piping shall be
						designed or located so that moisture cannot collect and freeze in a manner that
						would interfere with proper operation of the device.
2-2.4 Pressure relief valves for gaseous
						H2 service shall not be fitted with manual relief
						(lifting devices).
2-2.5 Pressure relief valves for gaseous
						H2 systems, if externally adjustable, shall be provided
						with a means for sealing the adjustment to prevent tampering.
2-2.5.1 If at any time it is necessary to break such a
						seal, the valve shall be removed from service until it has been reset and
						sealed in accordance with design, certification, and installation code
						specified in section 2-2.1.
2-2.6 Pressure relief valves shall be tested at least
						every 5 years.
Exception: Non-ASME relief valves used for blocked-in
						portions of piping as thermal relief valves will not be tested.
2-2.7 Excess flow control shall be provided for
						pressurized H2 piping systems above 15 psig when system
						design allows their application to add a significant measure of safety for
						break, rupture, or open valve (to atmosphere) conditions.
2-2.7.1 The location of excess flow control shall be as
						specified as in either of the following situations:
(a) Where piping originates from a source
					 located in a room or area, the excess flow control shall be located within the
					 same room or area.
(b) Where piping
					 originates from a bulk source, the excess flow control shall be as close to the
					 bulk source as possible.
Exception: The above requirements shall not apply to
						piping for inlet connections designed to prevent backflow, piping pressure
						relief devices, or systems containing 450 scf of H2 gas
						or less.