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Chemical Datasheet

HYDROGEN, REFRIGERATED LIQUID (CRYOGENIC LIQUID)

2.1 - Flammable gas

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 1333-74-0   (HYDROGEN)
  • 1966
  • Flammable Gas
  • HXX
NIOSH Pocket Guide International Chem Safety Card
none
  • HYDROGEN
NFPA 704
Diamond Hazard Value Description
4
3 0
Blue Health 3 Can cause serious or permanent injury.
Red Flammability 4 Burns readily. Rapidly or completely vaporizes at atmospheric pressure and normal ambient temperature.
Yellow Instability 0 Normally stable, even under fire conditions.
White Special
(NFPA, 2010)
General Description
A colorless very cold liquid shipped in special heavily insulated containers. Boils at -442°F. Contact causes severe frostbite. Hydrogen gas at normal temperatures is lighter than air but until vapors boiling off from the liquid warm up they are heavier than air. Very easily ignited. Burns with a pale blue, almost invisible flame. A leak could be either a vapor or a liquid leak. The container is designed to vent the vapor as it is boils off. Under prolonged exposure to intense heat the containers may rupture violently and rocket.

Hazards

Reactivity Alerts
Air & Water Reactions
Highly flammable.
Fire Hazard
Behavior in Fire: Burns with an almost invisible flame. (USCG, 1999)
Health Hazard
If atmosphere does not contain enough oxygen, inhalation can cause dizziness, unconsciousness, or even death. Contact of liquid with eyes or skin causes freezing similar to burn. (USCG, 1999)
Reactivity Profile
Finely divided platinum and some other metals will cause a mixture of hydrogen and oxygen to explode at ordinary temperatures. If a jet of hydrogen in air impinges on platinum black the metal surface gets hot enough to ignite the gases, [Mellor 1:325(1946-1947)]. Explosive reactions occur upon ignition of mixtures of nitrogen trifluoride with good reducing agents such as ammonia, hydrogen, hydrogen sulfide or methane. Mixtures of hydrogen, carbon monoxide, or methane and oxygen difluoride are exploded when a spark is discharged, [Mellor 2, Supp. 1:192(1956)]. An explosion occurred upon heating 1'-pentol and 1''-pentol under hydrogen pressure. It appears that this acetylenic compound under certain conditions suddenly breaks down to form elemental carbon, hydrogen, and carbon monoxide with the release of sufficient energy to develop pressures in excess of 1000 atmospheres, [AIChE Loss Prevention, p1, (1967)]. Contact of very cold liquefied gas with water may result in vigorous or violent boiling of the product and extremely rapid vaporization due to the large temperature differences involved. If the water is hot, there is the possibility that a liquid "superheat" explosion may occur. Pressures may build to dangerous levels if liquid gas contacts water in a closed container, [Handling Chemicals Safely 1980].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation
Excerpt from 115 Polymerizable warning [Gases - Flammable (Including Refrigerated Liquids)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 100 meters (330 feet) in all directions.

LARGE SPILL: Consider initial downwind evacuation for at least 800 meters (1/2 mile).

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 1600 meters (1 mile) in all directions; also, consider initial evacuation for 1600 meters (1 mile) in all directions. In fires involving Liquefied Petroleum Gases (LPG) (UN1075), Butane (UN1011), Butylene (UN1012), Isobutylene (UN1055), Propylene (UN1077), Isobutane (UN1969), and Propane (UN1978), also refer to BLEVE - SAFETY PRECAUTIONS (ERG page 366). (ERG, 2020)
Firefighting
Excerpt from 115 Polymerizable warning [Gases - Flammable (Including Refrigerated Liquids)]:

DO NOT EXTINGUISH A LEAKING GAS FIRE UNLESS LEAK CAN BE STOPPED. CAUTION: Hydrogen (UN1049), Deuterium (UN1957), Hydrogen, refrigerated liquid (UN1966) and Hydrogen and Methane mixture, compressed (UN2034) will burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.).

SMALL FIRE: Dry chemical or CO2.

LARGE FIRE: Water spray or fog. If it can be done safely, move undamaged containers away from the area around the fire. CAUTION: For LNG - Liquefied natural gas (UN1972) pool fires, DO NOT USE water. Use dry chemical or high-expansion foam.

FIRE INVOLVING TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Do not direct water at source of leak or safety devices; icing may occur. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2020)
Non-Fire Response
Excerpt from 115 Polymerizable warning [Gases - Flammable (Including Refrigerated Liquids)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. If possible, turn leaking containers so that gas escapes rather than liquid. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. Do not direct water at spill or source of leak. CAUTION: For LNG - Liquefied natural gas (UN1972), DO NOT apply water, regular or alcohol-resistant foam directly on spill. Use a high-expansion foam if available to reduce vapors. Prevent spreading of vapors through sewers, ventilation systems and confined areas. Isolate area until gas has dispersed. CAUTION: When in contact with refrigerated/cryogenic liquids, many materials become brittle and are likely to break without warning. (ERG, 2020)
Protective Clothing
Safety goggles or face shield; insulated gloves and long sleeves; cuffless trousers worn outside boots or over high-top shoes to shed spilled liquid; self-contained breathing apparatus containing air (never use oxygen). (USCG, 1999)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
The only effect of exposure to liquid hydrogen is that caused by its unusually low temperature and its action as a simple asphyxiant.

INHALATION: if victim is unconscious (due to oxygen deficiency), move him to fresh air and apply resuscitation methods; call physician.

EYES: treat for frostbite.

SKIN: treat for frostbite; soak in lukewarm water; get medical attention if burn is severe. (USCG, 1999)

Physical Properties

Chemical Formula:
  • H2
Flash Point: data unavailable
Lower Explosive Limit (LEL): 4 % (USCG, 1999)
Upper Explosive Limit (UEL): 75 % (USCG, 1999)
Autoignition Temperature: 1065°F (USCG, 1999)
Melting Point: -434°F (USCG, 1999)
Vapor Pressure: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 0.071 at -423.4°F (USCG, 1999) - Less dense than water; will float
Boiling Point: -423°F at 760 mmHg (USCG, 1999)
Molecular Weight: 2 (USCG, 1999)
Water Solubility: data unavailable
Ionization Energy/Potential: data unavailable
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Hydrogen (1333-74-0) 65000 ppm 3-flame icon indicates value is 100% or more of LEL. 230000 ppm 3-flame icon indicates value is 100% or more of LEL. 400000 ppm 3-flame icon indicates value is 100% or more of LEL. LEL = 40000 ppm
3-flame icon indicates value is 100% or more of LEL.
(DOE, 2018)

Regulatory Information

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Hydrogen 1333-74-0 10000 pounds

(EPA List of Lists, 2022)

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

RELEASE THEFT SABOTAGE
Chemical of Interest CAS Number Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Hydrogen 1333-74-0 1.00 % 10000 pounds flammable

(CISA, 2007)

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names