First-Aid Procedures for Cryogenic-Induced Injuries

Direct physical contact with liquid hydrogen, cold vapor, or cold equipment can cause serious tissue damage. Momentary contact with a small amount of the liquid may not pose as great a danger of a burn because a protective vapor film may form. Danger of freezing occurs when large amounts are spilled, and exposure is extensive.

Any person suffering from cryogenic or cold related injuries should be moved to a safe location only when this can be accomplished without endangering other people. Evaporating liquid hydrogen creates hydrogen gas with a high likelihood of a flammable or explosive mixture arising. Evacuate immediately and call 911 for first responders and alert them to the potential presence of a liquid hydrogen release or spill.

Frozen tissue is painless and appears yellow and waxy. Tissue becomes painful and turns pink or red upon thawing.

Cardiac malfunctions are likely when the internal body temperature drops to 27°C (80° F), and death may result when the internal body temperature drops to 25°C (76° F). If the body temperature is depressed, the patient must be warmed gradually to avoid shock and/or cardiac malfunctions.

Education about the risks of cold injury as well as preventive and emergency care should be incorporated into training programs for operations and emergency response if liquid hydrogen will be used or stored at a site.

Medical assistance for a cryogenic-induced injury should be obtained as soon as possible. Treatment of frozen tissue requires medical supervision because incorrect first aid practices invariably aggravate the injury.

It is safest to do nothing except protecting the affected area with a loose cover and transporting the injured person to a medical facility.

Some important things to remember:

• Don't remove frozen gloves, shoes, or clothing.
• Don't massage affected body parts.
• Don't expose affected body parts to temperatures above 44°C (112° F), such as a heater or a fire.
• Don't use safety showers, eyewash fountains, or other sources of water.
• Don't apply snow or ice to affected area.
• Don't apply ointments.

References

G-095A-20017, ANSI/AIAA Guide to Safety of Hydrogen and Hydrogen Systems, can be purchased from www.aiaa.org.

Air Products Safetygram for Liquid Hydrogen (pdf, 122 kb)