California Code of Regulations › Title 8 - Industrial Relations › Division 1 - Department of Industrial Relations › Chapter 4 - Division of Industrial Safety › Subchapter 7 - General Industry Safety Orders › Group 20 - Flammable Liquids, Gases and Vapors › Article 138 - Hydrogen › Section 5473 - Specific Requirements

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
(a) 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
Size of
								  Hydrogen System
Nature of
								  Location
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 Permitted
Inside buildings not in a special room and
								  exposed to other occupancies
IV
Not Permitted
Not
								  Permitted
(b) 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.
(c) The distance 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.
(d) 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:
(1) In an adequately ventilated area
						as in Section
						5475(b).
(2) 20 feet from stored flammable materials
						or oxidizing gases.
(3) 25 feet
						from open flames, ordinary electrical equipment or other sources of
						ignition.
(4) 25 feet from
						concentrations of people.
(5) 50
						feet from intakes of ventilation or air conditioning equipment and air
						compressors.
(6) 50 feet from other
						flammable gas storage.
(7)
						Protected against damage or injury due to falling objects or working activity
						in the area.
(8) 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.
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
Wood
								  Frame
								  Construction*
10
25
50
Structure
Heavy
								  Timber, Noncombustible or Ordinary
								  Construction*
0
10
25*
Fire Resistive
								  Construction*
0
0
0
2.
Wall Openings
Not
								  above any part of a system
10
10
10
Above any part of a
								  system
25
25
25
3.
Flammable
								  liquids
0-1,000 gallons
10
25
25
above ground
In
								  excess of 1,000 gallons
25
50
50
4.
Flammable
								  liquids
Tank
10
10
10
below
								  ground--
0-1,000 gallons
Vent or
								  fill opening of tank
25
25
25
5.
Flammable
								  liquids
Tank
20
20
20
below
								  ground--
in excess of 1,000
								  gallons
Vent or fill opening of
								  tank
25
25
25
6.
Flammable gas
								  storage
0-15,000 CF capacity
10
25
25
age, either
								  high
pressure or low
								  pressure
in excess of 15,000 CF
								  capacity
25
50
50
7.
Oxygen
								  Storage
12,000 CF or less
Refer to NFPA No. 51, Gas
								  Systems for Welding and Cutting
More than 12,000
								  CF
Refer to NFPA No. 50, Bulk Oxygen Systems at Consumer
								  Sites
8.
Fast burning solids such
								  as ordinary lumber, excelsior or paper
50
50
50
9.
Slow burning solids such
								  as heavy timber or coal
25
25
25
10.
Open flames and other
								  sources of ignition
25
25
25
11.
Air compressor intakes or
								  inlets to ventilating or air-conditioning
								  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.
** 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.