Mich. Admin. Code R. 29.7105

Current through Vol. 24-21, December 1, 2024

Section R. 29.7105 - Special rooms

Rule 105. Sections 4-4 to 4-4.9.1, and table 4-4.9 of the storage and handling of gaseous and Liquefied H₂ code are added as follows:

4-4 Special rooms.

4-4.1 Floors, walls, and ceiling shall be constructed of noncombustible or limited-combustible materials. Interior walls or partitions shall have a fire resistance rating of at least 2 hours, shall be continuous from floor to ceiling, and shall be securely anchored. At least 1 wall shall be an exterior wall. Windows and doors shall be located so as to be readily accessible in case of emergency.

Exception: Window glazing may be of plastic.

4-4.1.1 Access from within the primary structure shall be made through 1 vapor-sealing, 2 hour, self-closing fire door.

4-4.2 Ventilation shall be provided as in section 4-4.3.

4-4.3 Deflagration venting shall be provided in exterior walls or roof only.

4-4.3.1 Vents shall be any 1 or any combination of the following:

(a) Walls of light material.

(b) Lightly fastened hatch covers.

(c) Lightly fastened, outward opening doors in exterior walls.

(d) Lightly fastened walls or roof.

(e) Other methods in accordance with NFPA 69, adopted by reference in section 8.

4-4.3.2 Where applicable, snow loads shall be considered.

4-4.3.3 The venting area shall be equal to not less than 1 cubic foot/30 cubic feet (1 cubic meter/9 cubic meters) of room volume.

4-4.4 There shall be no sources of ignition.

4-4.5 Electrical wiring and equipment shall comply with section 2-7, except that all electrical wiring and equipment in the special room shall be class I, division 2, group B.

4-4.6 Heating, if provided, shall be by steam, hot water, or other indirect means.

Exception: Electrical heating shall be in accordance with section 4-4.5.

4-4.7 Room ventilation.

4-4.7.1 The ventilation shall be at least 1 cubic foot/minute/square foot of room area, but not less than 1 cubic foot/minute/12 cubic feet of room volume and shall be designed such that an accumulation of H₂ at a concentration equal to or greater than 25% of the lower flammable limit shall not occur in any part of the room.

4-4.7.2 Ventilation shall be by a continuous mechanical ventilation system or by a mechanical ventilation system activated by a continuously monitoring H₂ detection system where a gas concentration of not more than 25% of the lower flammable limit is present.

4-4.7.3 Where installed, a gas detection system shall be equipped to sound an alarm and visually indicate when a maximum of 25% of the lower flammable limit is reached.

4-4.7.4 Any failure of the ventilation system shall immediately shut down the fueling system and provide notification to the system operator. Reactivation of the fueling system shall be by manual restart and shall be conducted by trained personnel.

4-4.7.5 The gas detection system shall function during ventilation system maintenance operations.

4-4.7.6 A ventilation system for a room within or attached to another building shall be designed to ensure that all areas serviced by the ventilation system meeting performance requirements in accordance with section 4-4.7 during the normal operating conditions and during alarm conditions.

4-4.8 Warning signs.

4-4.8.1 Access doors shall have warning signs with the words "WARNING - NO SMOKING - NONORDORIZED FLAMMABLE GAS - CRYOGENIC LIQUID -COLD GAS - NO OPEN FLAMES." The wording shall be in plainly legible, bright red letters not less than 1 inch (2.54 centimeters) high on a white background.

4-4.9 Indoor attended gaseous H₂ fast-fill fueling.

4-4.9.1 Attended indoor fast-fill fueling system shall be in accordance with subsections (a) to (k) of this section.

(a) Gas storage equipment shall be located outdoors unless approved by the department. Gas processing and compression equipment shall be listed or approved for indoor use or located outdoors.

(b) An emergency manual shutdown device shall be located in the dispensing area not less than 20 feet (6.1 meters) and not more than 100 feet (30.5 meters) in the path of egress from the dispensing area. Actuation of the emergency manual shutdown device shall perform in accordance with subsection (h) of this section.

(c) The dispenser shall be equipped with a gas detection system which shall actuate in accordance with subsection (h) of this section when a maximum of 25% of LFL is detected (1% H₂ in air).

(d) The dispenser shall be equipped with a leak detection system capable of identifying a leak from the dispensing system outside the dispenser housing by conducting a pre-fill pressure test. The leak detection must be capable of detecting a minimum leak rate of 1.9 gallon/minute (7.2 liter/minute) and shall actuate in accordance with subsection (h) of this section when a leak is detected.

(e) Whether the fill is communicated or non-communicated, the dispensing system must be listed, labeled or approved to insure that the fills are protective of the safety of the temperature, pressure and flow rate limits of the on-board fuel system during fueling.

(f) The dispensing area shall be equipped with a fire detection system and shall actuate in accordance with subsection (i) of this section if a fire is detected.

(g) A ventilation system shall be installed for the dispensing area. The ventilation system shall be capable of delivering ventilation air as provided in section 4.3.7. The ventilation system shall operate prior to dispenser operation, during fueling, and for at least 1 minute after fueling has been completed. The ventilation flow rate shall be monitored. Failure or reduction of the ventilation flow rate below the required flow rate shall shut down the dispensing system.

Exemption: A dispensing area ventilation system is not required when the fuel delivery per refueling event is less than those listed in table 4-4.9.

Table 4-4.9

Room Size (m3)	Maximum fuel delivery per refueling event that does not require room ventilation (kg)
1000	0. 8
2000	1.7
3000	2.5
4000	3.3
5000	4.2

(h) The actuation of any 1 of the systems listed in subsections (b) to (g) of this section shall shut down the dispenser, stop the flow of gas into the room, and start or continue to run the ventilation system, if required, it shall be in accordance with table 4-4.9.

(1) Reactivation of the dispenser and gas flow into the room shall be by manual restart and shall be conducted by trained personnel.

(i) Interior walls, doors, and window openings within 15 feet (4.6 meters) of the dispenser shall be constructed of materials having a fire rating of at least 2 hours. Wall penetrations shall require use of listed fire-rated equipment.

(j) The owner/operator shall not allow hot work/open flames within 15 feet (4.6 meters) of the refueling location unless the dispenser is shut down, depressurized, and purged.

(k) If H₂ is to be removed from the vehicle storage system, H₂ shall be discharged into a closed transfer system or vented outdoors in accordance with CGA G-5.5, "Hydrogen Vent Systems," as adopted by reference in section 8.

Mich. Admin. Code R. 29.7105

2008 AACS