WAC 296-24-31503   Gaseous hydrogen systems.  (1) Design.

     (a) Containers.

     (i) Hydrogen containers shall comply with one of the following:

     (A) Designed, constructed, and tested in accordance with appropriate requirements of ASME Boiler and Pressure Vessel Code, Section VIII -- Unfired Pressure Vessels -- 1968.

     (B) Designed, constructed, tested and maintained in accordance with U.S. Department of Transportation specifications and regulations.

     (ii) Permanently installed containers shall be provided with substantial noncombustible supports on firm noncombustible foundations.

     (iii) Each portable container shall be legibly marked with the name "hydrogen" in accordance with "marking compressed gas containers to identify the material contained" ANSI Z48.1-1954. Each manifolded hydrogen supply unit shall be legibly marked with the name hydrogen or a legend such as "this unit contains hydrogen."

     (b) Safety relief devices.

     (i) Hydrogen containers shall be equipped with safety relief devices as required by the ASME Boiler and Pressure Vessel Code, Section VIII Unfired Pressure Vessels, 1968 or the DOT specifications and regulations under which the container is fabricated.

     (ii) Safety relief devices 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 structure of personnel. This requirement does not apply to DOT specification containers having an internal volume of 2 cubic feet or less.

     (iii) Safety relief devices or vent piping shall be designed or located so that moisture cannot collect and freeze in a manner which would interfere with proper operation of the device.

     (c) Piping, tubing, and fittings.

     (i) Piping, tubing, and fittings shall be suitable for hydrogen service and for the pressures and temperatures involved. Case iron pipe and fittings shall not be used.

     (ii) Piping and tubing shall conform to Section 2 -- "Industrial Gas and Air Piping" -- Code for Pressure Piping, ANSI B31.1-1967 with addenda B31.1-1969.

     (iii) Joints in piping and tubing may be made by welding or brazing or by use of flanged, threaded, socket, or compression fittings. Gaskets and thread sealants shall be suitable for hydrogen service.

     (d) Equipment assembly.

     (i) Valves, gauges, regulators, and other accessories shall be suitable for hydrogen service.

     (ii) Installation of hydrogen systems shall be supervised by personnel familiar with proper practices with reference to their construction and use.

     (iii) Storage containers, piping, valves, regulating equipment, and other accessories shall be readily accessible, and shall be protected against physical damage and against tampering.

     (iv) Cabinets or housings containing hydrogen control or operating equipment shall be adequately ventilated.

     (v) Each mobile hydrogen supply unit used as part of a hydrogen system shall be adequately secured to prevent movement.

     (vi) Mobile hydrogen supply units shall be electrically bonded to the system before discharging hydrogen.

     (e) Marking. The hydrogen storage location shall be permanently placarded as follows: "HYDROGEN -- FLAMMABLE GAS -- NO SMOKING -- NO OPEN FLAMES," or equivalent.

     (f) Testing. After installations, all piping, tubing, and fittings shall be tested and proved hydrogen gas tight at maximum operating pressure.

     (2) Location.

     (a) General.

     (i) The system shall be located so that it is readily accessible to delivery equipment and to authorized personnel.

     (ii) Systems shall be located above ground.

     (iii) Systems shall not be located beneath electric power lines.

     (iv) Systems shall not be located close to flammable liquid piping or piping of other flammable gases.

     (v) Systems near aboveground flammable liquid storage shall be located on ground higher than the flammable liquid storage except when dikes, diversion curbs, grading, or separating solid walls are used to prevent accumulation of flammable liquids under the system.

     (b) Specific requirements.

     (i) The location of a system, as determined by the maximum total contained volume of hydrogen, shall be in the order of preference as indicated by Roman numerals in Table H-1.

TABLE H-1



Nature of location Size of

hydrogen system
  Less

than

3,000

CF		 3,000

CF to 15,000

CF		   In

excess of

15,000

CF
Outdoors ————————–– I ———— I ———— I.
In a separate building ———— II ———— II ———— II.
In a special room —————— III ———— III ———— Not

per-

mitted.
Inside buildings not in

     a special room and

     exposed to other

     occupancies —————–

IV




 ———





Not

per-

mitted.
 ———




 Not

per-

mitted.

     (ii) The minimum distance in feet from a hydrogen system of indicated capacity located outdoors, in separate buildings or in special rooms to any specified outdoor exposure shall be in accordance with Table H-2.

     (iii) The distances in Table H-2 Items 1, 14, and 3 to 10 inclusive do not apply where protective structures such as adequate fire walls are located between the system and the exposure.

     (iv) Hydrogen systems of less than 3,000 CF when located inside buildings and exposed to other occupancies shall be situated in the building so that the system will be as follows:

     (A) In an adequately ventilated area as in (3)(b)(ii) of this section.

     (B) Twenty feet from stored flammable materials or oxidizing gases.

     (C) Twenty-five feet from open flames, ordinary electrical equipment or other sources of ignition.

     (D) Twenty-five feet from concentrations of people.

     (E) Fifty feet from intakes of ventilation or air-conditioning equipment and air compressors.

     (F) Fifty feet from other flammable gas storage.

     (G) Protected against damage or injury due to falling objects or working activity in the area.

     (H) More than one system of 3,000 CF or less may be installed in the same room, provided the systems are separated by at least 50 feet. Each such system shall meet all of the requirements of this section.

     (3) Design consideration at specific locations.

     (a) Outdoor locations.

     (i) Where protective walls or roofs are provided, they shall be constructed of noncombustible materials.

     (ii) Where the enclosing sides adjoin each other, the area shall be properly ventilated.

     (iii) Electrical equipment shall meet the requirements for Class I, Division 2 hazardous locations of WAC 296-24-95613.

     (b) Separate buildings.

     (i) Separate buildings shall be built of at least noncombustible construction. Windows and doors shall be located so as to be readily accessible in case of emergency. Windows shall be of glass or plastic in metal frames.

     (ii) Adequate ventilation to the outdoors shall be provided. Inlet openings shall be located near the floor in exterior walls only. Outlet openings shall be located at the high point of the room in exterior walls or roof. Inlet and outlet openings shall each have minimum total area of one square foot per 1,000 cubic feet of room volume. Discharge from outlet openings shall be directed or conducted to a safe location.

     (iii) Explosion venting shall be provided in exterior walls or roof only. The venting area shall be equal to not less than 1 square foot per 30 cubic feet of room volume and may consist of any one or any combination of the following: Walls of light noncombustible material, preferably single thickness, single strength glass; lightly fastened hatch covers; lightly fastened swinging doors in exterior walls opening outward; lightly fastened walls or roof designed to relieve at a maximum pressure of 25 pounds per square foot.

     (iv) There shall be no sources of ignition from open flames, electrical equipment, or heating equipment.

     (v) Electrical equipment shall meet the requirements of chapter 296-24 WAC Part L.

     (vi) Heating, if provided, shall be by steam, hot water, or other indirect means.

     (c) Special rooms.

     (i) Floor, walls, and ceiling shall have a fire-resistance rating of at least 2 hours. Walls or partitions shall be continuous from floor to ceiling and shall be securely anchored. At least one wall shall be an exterior wall. Openings to other parts of the building shall not be permitted. Windows and doors shall be in exterior walls and shall be located so as to be readily accessible in case of emergency. Windows shall be of glass or plastic in metal frames.

     (ii) Ventilation shall be as provided in (3)(b)(ii) of this section.

     (iii) Explosion venting shall be as provided in (3)(b)(iii) of this section.

     (iv) There shall be no sources of ignition from open flames, electrical equipment or heating equipment.

     (v) Electrical equipment shall meet the requirements of chapter 296-24 WAC Part L.

     (vi) Heating, if provided, shall be by steam, hot water, or indirect means.

     (4) Operating instructions. For installations which require any operation of equipment by the user, legible instructions shall be maintained at operating locations.

     (5) Maintenance.

     (a) The equipment and functioning of each charged gaseous hydrogen system shall be maintained in a safe operating condition in accordance with the requirements of this section. The area within 15 feet of any hydrogen container shall be kept free of dry vegetation and combustible material.
TABLE H-2

  Size of

hydrogen system
  Type of outdoor exposure
Less

than

3,000

CF
3,000

CF

to

15,000

CF
In

excess

of

15,000

CF
1. Building or

structure ———–

Wood frame construction*

Heavy timber, noncombustible or ordinary construction*

Fire-resistive construction*



- 10






- 0



- 0



25






10



0
  



50






**25



0
  
2. Wall openings - Not above any part of a system —–––

Above any part of a system ———

10



25

10



25		  

10



25		  
3. Flammable liq-

uids above

ground ————



0 to 1,000 gallons

In excess of 1,000 gallons ———



- 10



- 25



25



50		  



25



50
4. Flammable

liquids below

ground----0 to

1,000 gallons





-





Tank ——————

Vent or fill opening of tank ———





- 10



25





10



25		  





10



25
5. Flammable

liquids below

ground----in

excess of

1,000 gallons







-







Tank ——————

Vent or fill opening of tank ———







- 20



25







20



25		  







20



25
6. Flammable gas

storage, either

high pressure or

low pressure ——





0 to 15,000 CF capacity ——–

In excess of 15,000 CF capacity —







- 10



25







25



50		  







25



50		  
7.





 Oxygen storage





 -





 12,000 CF or less





 -





 Refer to NFPA No. 51, gas systems for welding and cutting (1969).
  More than 12,000 CF





 -





 Refer to NFPA No. 566, bulk oxygen systems at consumer sites (1969).
8. Fast burning

solids such as

ordinary lumber,

excelsior or paper ————————–





50





50		  





25
9. Slow burning solids

such as heavy timber

or coal ————————————––



25



25		  



25
10. Open flames and other

sources of ignition ————————–

25

25		  

50
11. Air compressor intakes

or inlets to ventilating

or air-condition

equipment ———————————–





50





50		  





50
12. Concentration of people*** ————– 25 50   50  
13. Public sidewalks ————————— 15 15   15  
14. Line of adjoining

property which may be

built upon ———————————–



5
  



5
  



5
  

* Refer to NFPA No. 220 standard types of building construction for definitions of various types of construction. (1969 Ed.)
** But not less than one-half the height of adjacent side wall of the structure.
*** In congested areas such as offices, lunchrooms, locker rooms, time-clock areas, and places of public assembly.




[Statutory Authority: Chapter 49.17 RCW. 91-24-017 (Order 91-07), § 296-24-31503, filed 11/22/91, effective 12/24/91; 88-23-054 (Order 88-25), § 296-24-31503, filed 11/14/88. Statutory Authority: RCW 49.17.040 and 49.17.050. 85-10-004 (Order 85-09), § 296-24-31503, filed 4/19/85; Order 76-6, § 296-24-31503, filed 3/1/76; Order 73-5, § 296-24-31503, filed 5/9/73 and Order 73-4, § 296-24-31503, filed 5/7/73.]