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SECTION 1. CHEMICAL IDENTIFICATION

CHEMINFO Record Number: 148
CCOHS Chemical Name: Hydrogen

Synonyms:
Hydrogen gas
Hydrogen, compressed
Molecular hydrogen
Protium
Hydrogen, refrigerated liquid
Hydrogen, refrigerated liquefied gas
Cryogenic hydrogen

Chemical Name French: Hydrogène
Chemical Name Spanish: Hidrógeno
CAS Registry Number: 1333-74-0
UN/NA Number(s): 1049
RTECS Number(s): MW8900005
EU EINECS/ELINCS Number: 215-605-7
Chemical Family: Hydrogen and compounds / molecular hydrogen
Molecular Formula: H2
Structural Formula: H-H

SECTION 2. DESCRIPTION

Appearance and Odour:
Colourless, odourless gas or extremely cold liquid.(1,8)

Odour Threshold:
Hydrogen is odourless.

Warning Properties:
NONE - hydrogen is an odourless, non-irritating gas.

Composition/Purity:
Hydrogen is available commercially as a compressed gas and as a cryogenic liquid. Gaseous hydrogen is typically 97 to greater than 99.5 volume % pure. The impurities present depend on the method of production and purification stages and may include nitrogen, traces of oxygen, carbon monoxide, carbon dioxide, inert gases (e.g. helium, neon and argon), hydrocarbons (e.g. methane, ethane, ethylene, propane and propylene), hydrogen sulfide, sulfur dioxide and ammonia.(9) Hydrogen gas is usually shipped as a non-liquefied gas in high-pressure cylinders at pressures of 15170 kPa (149.7 atm) to 16550 kPa (163.3 atm) at 21.1 deg C and at lower pressures in smaller cylinders and lecture bottles. Hydrogen gas is also shipped in tube trailers and tank cars.(8) Cryogenic hydrogen is shipped in specification insulated welded cylinders, insulated cargo tanks, cryogenic tank cars and insulated portable tanks.(8) Large quantities of hydrogen are shipped in pipelines. Pipeline networks are available in Alberta, Canada, the United States and in a number of countries in Northern Europe.(9,10)

Uses and Occurrences:
The largest use of hydrogen is for the manufacture of ammonia. Other important uses are in petroleum refineries to desulfurize or hydrogenate various petroleum products derived from crude oil into transportation fuels; for the manufacture of other chemicals including methanol, cyclohexane, hexamethylene diamine, toluene diamine, and aniline; used in coal refinement and as a synthesis gas.
Hydrogen is also used for the hydrogenation of vegetable and animal fats; in the metallurgy industry to reduce metal oxides and prevent oxidation of metals in heat treating certain ferrous metals and alloys; in hydrometallurgical processes for metal production of tungsten, molybdenum and magnesium; as a reducing agent; as a utility in some powder metallurgy production processes; used with oxygen in a high temperature oxyhydrogen flame for cutting and autogenous welding in the metal industry; for plasma welding and cutting; in atomic hydrogen welding; for growing synthetic crystals (sapphires, rubies); for production and handling of quartz glass; in water treatment; as alloying element in metals to produce required chemical properties; in the electronics industry in semiconductor manufacture, quartz melting, polysilicone manufacture and fibre optic manufacture; in float glass production plants; to cool generators in electric power plants; to prevent corrosion in nuclear power plants; and as a carrier and fuel gas in gas chromatography.(1,8,9,10)
Refrigerated liquefied hydrogen is used in rocket propulsion and scientific experiments, e.g. bubble chambers.(9)
Hydrogen is present in the atmosphere at about 0.5 ppm by volume at lower altitudes.(8)


SECTION 3. HAZARDS IDENTIFICATION

EMERGENCY OVERVIEW:
Colourless, odourless gas or extremely cold liquid. EXTREMELY FLAMMABLE GAS or REFRIGERATED LIQUEFIED GAS. Forms explosive mixtures with air over an extremely wide concentration range. Burns with an extremely hot, nearly invisible flame. Confined space explosion and asphyxiation hazard. Very low ignition energy. May be ignited by weak ignition sources, like static charges on clothing or people. Refrigerated liquefied hydrogen can accumulate static charge by flow, friction in pipes, splashing and agitation. COMPRESSED GAS. Cylinders and closed containers may rupture violently if heated. Release of hydrogen gas from a pressure container will cause the container to heat up, which may result in ignition of the gas or overpressurization of the container. Because of the extremely cold temperature of refrigerated liquefied hydrogen, there is a danger of air liquefaction and oxygen-enrichment. Air will condense on external surfaces, cooled by refrigerated liquefied hydrogen, such as vessels, or uninsulated pipes. The liquid air produced can result in oxygen-enrichment of the atmosphere, close to the equipment or in confined areas. Oxygen-enriched liquid air may cause a fire if it comes into contact with combustible surfaces or materials. Essentially non-toxic at normal temperature and pressure. Simple asphyxiant. High concentrations can displace oxygen in the air and cause suffocation. Direct contact with compressed gas or refrigerated liquefied gas can cause cold burns or frostbite.



POTENTIAL HEALTH EFFECTS

Effects of Short-Term (Acute) Exposure

Inhalation:
Hydrogen gas is not toxic at normal temperature and pressure, but is an extremely flammable gas, posing a very serious fire hazard. When hydrogen is present in high concentrations in air it acts as a simple asphyxiant. Simple asphyxiants displace oxygen in the air and can cause symptoms of oxygen deprivation (asphyxiation) when present in high enough concentrations to lower the oxygen concentration. The available oxygen should be a minimum of 18% or harmful effects will result.(5)
Hydrogen gas can be liquefied under extreme pressures and very low temperatures. The gas can be released in very large quantities from pressurized tanks. If this happens in a confined space, or a space that is not well ventilated, the percentage of oxygen can very quickly reduce to dangerous levels.
Effects of oxygen deficiency are: 12-16%: breathing and pulse rate are increased, with slight muscular incoordination; 10-14%: emotional upsets, abnormal fatigue from exertion, disturbed respiration; 6-10%: nausea and vomiting, inability to move freely, collapse, possible lack of consciousness; below 6%: convulsive movements, gasping, possible respiratory collapse and death. Since exercise increases the body's need for oxygen, symptoms will occur more quickly during exertion in an oxygen-deficient environment.(6,7) In survivors of oxygen deprivation, some or all organs, including the central nervous system and the brain, may have damage from low oxygen. These effects may or may not be reversible with time, depending on the degree and duration of the low oxygen and the amount of tissue injury.(7)

Skin Contact:
Hydrogen gas is not irritating.
Direct contact with compressed hydrogen escaping from its cylinder or refrigerated liquefied hydrogen can cause cold burns or frostbite (freezing of the tissue). Symptoms of mild frostbite include numbness, prickling and itching in the affected area. Symptoms of more severe frostbite include a burning sensation and stiffness of the affected area. The skin may become waxy white or yellow. Blistering, tissue death and gangrene may also develop in severe cases.

Eye Contact:
Hydrogen gas is not irritating.
Direct contact with the compressed hydrogen escaping from its cylinder or refrigerated liquefied hydrogen can cause freezing of the eye. Permanent eye damage or blindness could result.

Ingestion:
Ingestion exposure is not applicable to gases.

Effects of Long-Term (Chronic) Exposure

There is no human or animal information available. Hydrogen is not expected to cause health effects following long-term exposure.

Carcinogenicity:

No specific human or animal information was located. Hydrogen is not expected to cause cancer.

The International Agency for Research on Cancer (IARC) has not evaluated the carcinogenicity of this chemical.

The American Conference of Governmental Industrial Hygienists (ACGIH) has not assigned a carcinogenicity designation to this chemical.

The US National Toxicology Program (NTP) has not listed this chemical in its report on carcinogens.

Teratogenicity and Embryotoxicity:
No specific human or animal information was located. Hydrogen is not expected to cause developmental effects.

Reproductive Toxicity:
No specific human or animal information was located. Hydrogen is not expected to cause reproductive effects.

Mutagenicity:
No specific information was located. Hydrogen is not expected to be mutagenic.

Toxicologically Synergistic Materials:
There is no information available.

Potential for Accumulation:
Hydrogen gas does not accumulate in the body.


SECTION 4. FIRST AID MEASURES

Inhalation:
This is chemical is extremely flammable. Take proper precautions (e.g. remove any sources of ignition). In general, this gas has very low toxicity, but it can act as an asphyxiant at high concentrations. If the victim has been knocked down, wear appropriate protective equipment, and use the buddy system. Remove source of contamination or move victim to fresh air. If breathing is difficult, trained personnel should administer emergency oxygen. If breathing has stopped, trained personnel should begin artificial respiration (AR) or, if the heart has stopped, cardiopulmonary resuscitation (CPR) or automated external defibrillation (AED) immediately. Quickly transport victim to an emergency care facility.

Skin Contact:
COMPRESSED OR REFRIGERATED LIQUEFIED GAS: Quickly remove victim from source of contamination and briefly flush with lukewarm, gently flowing water. DO NOT attempt to rewarm the affected area on site. DO NOT rub area or apply dry heat. Gently remove clothing or jewelry that may restrict circulation. Carefully cut around clothing that sticks to the skin and remove the rest of the garment. Loosely cover the affected area with a sterile dressing. DO NOT allow the victim to drink alcohol or smoke. Immediately obtain medical attention. GAS: Not applicable. No effects expected.

Eye Contact:
COMPRESSED OR REFRIGERATED LIQUEFIED GAS: Quickly remove victim from source of contamination. Immediately and briefly flush with lukewarm, gently flowing water. DO NOT attempt to rewarm. Cover both eyes with a sterile dressing. DO NOT allow victim to drink alcohol or smoke. Quickly transport victim to an emergency medical facility. GAS: Not applicable. No effects expected.

Ingestion:
Ingestion is not an applicable route of exposure for gases.

First Aid Comments:
Provide general supportive measures (comfort, warmth, rest).
Consult a doctor and/or the nearest Poison Control Centre for all exposures except minor instances of inhalation.
Some first aid procedures recommended above require advanced first aid training. Protocols for undertaking advanced procedures must be developed in consultation with a doctor and routinely reviewed.
All first aid procedures should be periodically reviewed by a doctor familiar with the material and its condition of use in the workplace.



SECTION 5. FIRE FIGHTING MEASURES

Flash Point:
Flammable gas (burns at all ambient temperatures)

Lower Flammable (Explosive) Limit (LFL/LEL):
4.0% (2,10)

Upper Flammable (Explosive) Limit (UFL/UEL):
75% (2,10)

Autoignition (Ignition) Temperature:
Reported values vary and depend on measurement conditions.(11) 585 deg C (1085 deg F) (9,10,12); also reported as 400 deg C (752 deg F) (1,2) and 500 deg C (932 deg F) (2)

Sensitivity to Mechanical Impact:
Probably not sensitive. Stable gas or refrigerated liquid.

Sensitivity to Static Charge:
Liquid hydrogen can accumulate static charge by flow, friction in pipes, splashing or agitation, since it has a very low electrical conductivity.(11,12,13) Gas in the flammable range can be ignited readily by a static discharge of sufficient energy.

Other Fire Properties:
Hydrogen does not autorefrigerate. If hydrogen escapes from a pressure tank or cylinder, it will cause the tank or cylinder to heat up. This can result in ignition of the hydrogen gas or possible overpressurization of the container.(24)

Electrical Conductivity:
Not applicable for hydrogen gas. Liquid: 2.17 x 10(-6) pS/m (reported as electrical resistance of 4.6 x10(19) ohm-cm) (12,13)

Minimum Ignition Energy:
0.02 millijoules (9,13)

Combustion and Thermal Decomposition Products:
The only combustion product is water vapour.

Fire Hazard Summary:
EXTREMELY FLAMMABLE COMPRESSED GAS or REFRIGERATED LIQUEFIED GAS. Hydrogen gas will readily ignite at room temperature. The flame spreads rapidly and burns with an extremely hot (2045 deg C (3713 deg F)), nearly invisible to bluish flame that is often difficult to see in daylight (visibility is improved by moisture and impurities in the air). Forms flammable and explosive mixtures with air over an extremely wide range of concentrations. The flammability limit range increases with temperature. Very low ignition energy. May be ignited by weak ignition sources, like static charges on clothing or people, or matches. Highly explosive in the presence of sparks, heat, fire and oxidizing agents. Electrostatic charges can build up as a result of flow or friction in pipes, splashing or agitation. This electrostatic build-up can cause ignition where gas is venting to the air.(11) High concentrations can displace oxygen in the air, causing suffocation (simple asphyxiant). COMPRESSED GAS. Heat from fire can cause a rapid build-up of pressure inside cylinders, which may cause explosive rupture and a sudden release of large amounts of extremely flammable hydrogen gas or may cause cylinder to rocket. Leaking hydrogen from a pressure tank or cylinder will cause the tank or cylinder to heat up. This can result in ignition of the gas or overpressurization of the container.(24) REFRIGERATED LIQUEFIED GAS. The volume of a given quantity of refrigerated liquefied hydrogen at 101.33 kPa (1 atm) and -268 deg C increases 850 times when warmed to room temperature.(14) The rapid expansion of refrigerated hydrogen liquid to gas in sealed non-vented containers (e.g. cold traps) can cause the vessels to burst. Spilled liquefied hydrogen is a fire risk and may readily ignite. Liquefied hydrogen can be particularly dangerous during fires because of its potential to rapidly freeze water, possibly blocking pressure relief valves. Relatively warm water greatly increases the evaporation rate of liquefied hydrogen gas. If large concentrations of cold gas are present that have originated from the cold, refrigerated liquid hydrogen, the water vapour in the surrounding air will condense, creating a dense fog that may make it difficult to find fire exits or equipment. Because of the extremely cold temperature of refrigerated liquefied hydrogen, there is a danger of air liquefaction and oxygen-enrichment of the liquefied air.(11,14) Air will condense on external hydrogen-cooled surfaces, such as vessels, or exposed, uninsulated or inadequately insulated pipes. The liquid air produced can result in oxygen-enrichment of the atmosphere, close to the equipment or in confined areas. Oxygen-enriched liquid air may cause a fire if it comes into contact with combustible surfaces or materials. The extremely low temperature of liquefied hydrogen can solidify any gas except helium. The solidified gases can plug restricted areas, such as valves or small openings and cause equipment failure. If air or oxygen is allowed to condense or solidify in liquefied hydrogen, a potential explosion hazard can result.(11,13)

Extinguishing Media:
Carbon dioxide, dry chemical powder, appropriate foam, water spray or fog. Foam manufacturers should be consulted for recommendations regarding types of foams and application rates.

Fire Fighting Instructions:
Use extreme caution. Explosions may occur under fire conditions. Heat may rupture containers. Fight fire from a protected, explosion-resistant location or maximum possible distance. The high-temperature hydrogen flame is practically invisible. When approaching hydrogen containers that may be on fire, carry something combustible which will burst into flame if there is contact with a hydrogen flame.
For fires involving flammable gases, the best procedure is to stop the flow of gas before attempting to extinguish the fire. It is extremely dangerous to extinguish the fire while allowing continued flow of the gas. The gas could form an explosive mixture with air and reignite, which may cause far more damage than if the original fire had been allowed to burn. In some cases, extinguishing the fire with carbon dioxide or dry chemical powder may be necessary to permit immediate access to valves to shut off the flow of gas. However, this must be done extremely carefully. Although some carbon monoxide may be formed if carbon dioxide is used as an extinguishant, it will not be in large amounts.(12) If it is not possible to stop the flow of gas and if there is no risk to the surrounding area, allow the fire to continue burning under control while protecting exposed materials with water spray, to prevent ignition of other combustible materials. Liquid spills should be allowed to burn until consumed. Water spray or fog can be used to extinguish any secondary fires and prevent the spread of the fire. Gas clouds may be controlled by water spray or fog.
Isolate containers exposed to heat, but not directly involved in the fire and protect personnel. Move cylinders/containers from fire area, if this can be done without risk. Handle damaged cylinders with extreme care. Otherwise, fire-exposed containers, cylinders, tanks, pipelines or hydrogen-containing equipment should be cooled by application of water-spray and this should begin as soon as possible (within the first several minutes) and should concentrate on any unwetted portions. No part of a cylinder should be subjected to a temperature higher than 52 deg C (approximately 125 deg F). If this is not possible, immediately evacuate the area and use unmanned monitor nozzles.
DO NOT direct water at open or leaking containers or cylinders and take precautions not to get water inside a container or cylinder or on or into vent openings. Reverse flow into cylinder may cause rupture. If large concentrations of gas are present that have originated from cold, refrigerated liquefied hydrogen, the water vapour in the surrounding air will condense, creating a dense fog that may reduce visibility. Closed containers may explode due to over pressurization when allowed to warm.
Refrigerated liquefied hydrogen can be particularly dangerous during fires because of its potential to rapidly freeze water. Take care when using water, since water can cause heavy icing. If possible, avoid spraying cold areas of containers or equipment to avoid rapid freezing of water, which can result in heavy icing and possible blockage of pressure release valves.
In an advanced or massive fire in a large area, the area should be evacuated; use unmanned hoseholders or monitor nozzles. If this is not possible, withdraw from fire area and do not attempt to fight the fire. Allow the fire to burn. Stay away from ends of tanks, but be aware that flying material from ruptured tanks and other containers may travel in any direction. Withdraw immediately in case of rising sound from venting safety device or any discolouration of tank due to fire.
After the fire has been extinguished, explosive, asphyxiant atmospheres may be present. Before entering such an area, especially confined areas, check the atmosphere with an appropriate monitoring device to determine if hydrogen is present and if there is sufficient oxygen.

Protection of Fire Fighters:
Hydrogen gas is an asphyxiant. Firefighters may enter the area if positive pressure self-contained breathing apparatus (NIOSH approved or equivalent) and full Bunker Gear is worn.



NATIONAL FIRE PROTECTION ASSOCIATION (NFPA) HAZARD IDENTIFICATION

NFPA - Health: 0 - Exposure, under fire conditions, would be no more hazardous than an ordinary combustible material. (Hydrogen gas) 3 - Short exposure could cause serious temporary or residual injury. (Hydrogen refrigerated liquid)
NFPA - Flammability: 4 - Will rapidly or completely vaporize at atmospheric pressure and normal ambient temperature, or readily disperse in air and burn readily. (Hydrogen gas and refrigerated liquid)
NFPA - Instability: 0 - Normally stable, even under fire conditions, and not reactive with water. (Hydrogen gas and refrigerated liquid)

SECTION 9. PHYSICAL AND CHEMICAL PROPERTIES

Molecular Weight: 2.016

Conversion Factor:
1 ppm = 0.08 mg/m3; 1 mg/m3 = 12.15 ppm at 25 deg C (calculated) 1 ppm = 0.08 mg/m3; 1 mg/m3 = 12.15 ppm at 25 deg C (calculated)

Physical State: Gas
Melting Point: -259.2 deg C (-434.6 deg F) (8,10)
Boiling Point: -252.8 deg C (-423 deg F) (8,15)
Relative Density (Specific Gravity): Not applicable (gas)
Solubility in Water: Slightly soluble (2.14 mL/100 g at 0 deg C (10); 1.9 mL/100 mL at 15.6 deg C (8); 0.162 mg/100 mL at 21 deg C (17))
Solubility in Other Liquids: Slightly soluble in ethanol and diethyl ether.
Coefficient of Oil/Water Distribution (Partition Coefficient): Log P(oct) = 0.45 (estimated) (18)
pH Value: Not applicable
Viscosity-Dynamic: Not applicable
Surface Tension: Not applicable
Vapour Density: 0.0695 (calculated) (air = 1)
Vapour Pressure: Not applicable (entirely gaseous above -240 deg C)
Vapour Pressure at 50 deg C: Greater than 7000 kPa (69 atm) (estimated from graph) (1)
Saturation Vapour Concentration: Not applicable
Evaporation Rate: Not applicable for the gas. Refrigerated liquefied gas will rapidly return to the gaseous state.
Henry's Law Constant: Not available
Critical Temperature: -240 deg C (-400 deg F) (8,15)
Critical Pressure: 1315 kPa (12.98 atm) (15)

Other Physical Properties:
TRIPLE POINT: -259.21 deg C (-434.6 deg F) at 7.23 kPa (8,10,15)
DIELECTRIC CONSTANT: 1.231 at -252.8 deg C (15)


SECTION 10. STABILITY AND REACTIVITY

Stability:
Stable gas and refrigerated liquefied gas.

Hazardous Polymerization:
Does not occur.

Incompatibility - Materials to Avoid:

NOTE: Chemical reactions that could result in a hazardous situation (e.g. generation of flammable or toxic chemicals, fire or detonation) are listed here. Many of these reactions can be done safely if specific control measures (e.g. cooling of the reaction) are in place. Although not intended to be complete, an overview of important reactions involving common chemicals is provided to assist in the development of safe work practices.


HALOGENS (e.g. bromine, chlorine or fluorine) or INTERHALOGENS (e.g. chlorine trifluoride, bromine trifluoride or iodine heptafluoride) - react explosively.(2,13,19)
OXIDIZING AGENTS (e.g. chlorine dioxide, dichlorine oxide, dinitrogen oxide, nitrogen oxide or fluorine perchlorate) - react explosively or ignite.(13,19)
NITROGEN TRIFLUORIDE or OXYGEN DIFLUORIDE - react explosively when ignited.(2)
PLATINUM - finely divided platinum and some other metals will cause hydrogen to react explosively with oxygen in air.(2)
MAGNESIUM and CALCIUM CARBONATE - a violent explosion occurs when the powdered metal and carbonate are heated in a stream of hydrogen.(2,19)
METALS (e.g. lithium, barium and strontium) - react readily and sometimes burn in gaseous hydrogen.(2,19)
SODIUM or POTASSIUM - react more slowly than lithium, barium or strontium to form the hydrides.(19)

Hazardous Decomposition Products:
None reported

Conditions to Avoid:
All ignition sources, like open flames, heat, sparks from electrical equipment and motors, static charges, friction, hot gases and surfaces. Liquid hydrogen must not be allowed to come unto contact with air.

Corrosivity to Metals:
Hydrogen embrittlement can occur at high temperatures and pressures and can seriously weaken or embrittle the metal. This can lead to hydrogen leaks.(9,10,13) Alloys and metals that resist hydrogen embrittlement at room temperature include aluminum (types 3003, 6061-T6 and 7075-T73), stainless steel (e.g. types 304, 316, 321, 347, 410, 440 series), oxygen-free copper and its alloys, brass, bronze, naval brass, and silicon bronze, nickel and nickel-base alloys, Monel, Hastelloy and Inconel, and titanium.(9,20) Decarburization happens in ferritic steels and alloys that contain carbon on contact with hydrogen, at temperatures greater than 200 deg C and causes these metals to weaken. Decarburization can be prevented by alloying metals such as chromium, molybdenum, tungsten, vanadium, titanium, and niobium.(9,10,13) At the extremely low temperature of liquid hydrogen, ordinary carbon steels and most alloy steels become brittle and are likely to break without warning.(8) Liquid hydrogen does not attack aluminum alloys, austenitic steels (300 series), nickel-iron, titanium, and copper alloys.(9)

Corrosivity to Non-Metals:
In general, plastics (e.g. Teflon, and other fluorocarbons, polyvinyl chloride (PVC), nylon, polyethylene, polypropylene and polyurethane) and elastomers (e.g. nitrile Buna-N (NBR), ethylene-propylene, Viton and other fluorocarbons, chloroprene and butyl rubber) are not subject to attack by hydrogen gas at ambient temperatures.(9,21,22,23) Hydrogen gas attacks elastomers, chlorinated polyethylene and polysulfide.(23)


SECTION 11. TOXICOLOGICAL INFORMATION

Hydrogen gas is essentially non-toxic at normal temperature and pressure. Therefore, very little information from toxicity testing is available.

Eye Irritation:

Hydrogen gas is not expected to be irritating to the eyes.

In a non-standard test, a large bubble of hydrogen gas injected into the front chamber of rabbit eyes was absorbed over 3 days and caused no injury.(4, unconfirmed)


SECTION 16. OTHER INFORMATION

Selected Bibliography:
(1) Yaws, C.L. Hydrogen. In: Matheson gas data book. 7th ed. McGraw Hill, 2001. p. 436-441
(2) Fire protection guide to hazardous materials. 13th ed. Edited by A.B. Spencer, et al. National Fire Protection Association, 2002. NFPA 325; NFPA 49; NFPA 491
(3) European Economic Community. Commission Directive 93/72/EEC. Sept. 1, 1993
(4) Grant, W.M. et al. Toxicology of the Eye. 4th ed. Charles C Thomas, 1993. p. 791
(5) American Conference of Governmental Industrial Hygienists (ACGIH). Hydrogen. Documentation of the Threshold Limit Values for Chemical Substances. 7th ed. ACGIH, 2001
(6) Leikauf, G.D., et al. Inorganic compounds of carbon, nitrogen and oxygen. In: Patty's Industrial Hygiene and Toxicology. 5th ed. Vol. 3. Edited by E. Bingham, et al. John Wiley & Sons, 2001
(7) Wilkenfeld, M. Simple asphyxiants. In: Environmental and Occupational Medicine. 3rd ed. Edited by W.N. Rom. Lippincott-Raven Publishers, 1998. p. 651-655
(8) Compressed Gas Association. Hydrogen. In: Handbook of compressed gases. 4th ed. Kluwer Academic Publishers, 1999. p. 415-427
(9) Häussinger, P., et al. Hydrogen. In: Ullmann's encyclopedia of industrial chemistry. 7th ed. John Wiley and Sons, 2002. Also available at: <www.mrw.interscience.wiley.com/ueic/ueic_search_fs.html> (Subscription required)
(10) Baade, W.F., et al. Hydrogen. In: Kirk-Othmer encyclopedia of chemical technology. John Wiley and Sons, 2001. Available at: <www.mrw.interscience.wiley.com/kirk/kirk_search_fs.html> (Subscription required)
(11) British Cryogenics Council. Cryogenics safety manual: a guide to good practice. 3rd ed. Butterworth Heinemann, 1991. p. 1-26, 77-93
(12) National Aeronautics and Space Administration (NASA). Safety standard for hydrogen and hydrogen systems: guidelines for hydrogen storage design, materials selection, operations, storage and transportation. NSS 1740.16. Office of Safety and Mission Assurance, National Aeronautics and Space Administration, 1997. Also available at: <www.hq.nasa.gov/office/codeq/doctree/871916.pdf>
(13) Kalyanam, K. M., et al. Safety guide for hydrogen. Hydrogen Safety Committee, National Research Council, 1987
(14) Compressed Gas Association. Safety considerations for compressed gases and cryogenic liquids. In: Handbook of compressed gases. 4th ed. Kluwer Academic Publishers, 1999. p. 16-39
(15) McCarty, R. D., et al. Selected properties of hydrogen (Engineering design data). US Department of Commerce, National Bureau of Standards, 1981. p. 1-26, 6-274, 6-289
(16) Hord, J. Is hydrogen a safe fuel? International Journal of Hydrogen Energy. Vol. 3 (1978). p. 157-176
(17) Syracuse Research Corporation. Hydrogen. In: The Physical Properties Database (PHYSPROP). Interactive PhysProp Database Demo. Date unknown. Available at: <www.syrres.com/esc/physdemo.htm>
(18) Syracuse Research Corporation. Interactive LogKow (KowWin) Database Demo. Date unknown. Available at: <syrres.com/esc/kowdemo.htm>
(19) Urben, P.G., ed. Bretherick's reactive chemical hazards database. [CD-ROM]. 6th ed. Version 3.0. Butterworth-Heinemann Ltd., 1999
(20) Hydrogen. In: Handbook of corrosion data. 2nd ed. Edited by B.D. Craig, et al. ASM International, 1995. p. 458-462
(21) Schweitzer, P.A. Corrosion resistance tables: metals, nonmetals, coatings, mortars, plastics, elastomers and linings, and fabrics. 4th ed. Part B, E-O. Marcel Dekker, Inc., 1995. p. 1529-1532
(22) Pruett, K.M. Chemical resistance guide for plastics: a guide to chemical resistance of engineering thermoplastics, fluoroplastics, fibers and thermoset resins. Compass Publications, 2000. p. 242-253
(23) Pruett, K.M. Chemical resistance guide for elastomers II: a guide to chemical resistance of rubber and elastomeric compounds. Compass Publications, 1994. p. C-188 to C-193
(24) American Society for Testing and Materials (ASTM). A guide to the safe handling of hazardous materials accidents. 2nd ed. ASTM manual series; MNL 10. American Society for Testing and Materials, 1990. p.32
(25) Air Products. Safety Infogram #9: Liquid Hydrogen. Available at: <http://www.airproducts.com/Responsibility/EHS/ProductSafety/ProductSafetyInformation/Safetygrams.htm>

Information on chemicals reviewed in the CHEMINFO database is drawn from a number of publicly available sources. A list of general references used to compile CHEMINFO records is available in the database Help.


Review/Preparation Date: 2005-10-03

Revision Indicators:
Vapour pressure at 50 deg C 2006-01-17
Relative density 2006-09-28



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