Exposure to cryogenic liquids or solids (very cold gases) can result in serious injury and even death.
Cryogenic liquids include liquid oxygen, liquid helium, liquid nitrogen, and liquid argon. Cryogenic solids include dry ice (carbon dioxide).
Exposure |
Risk |
direct contact with cryogenic compound or its vapor |
cold injury and frostbite |
direct contact of skin to a metal pipe, container, or absorptive glove containing the cryogenic compound |
tearing of skin and subcutaneous tissue |
rapid rise in pressure as cryogenic material changes to a gas in a contained space |
explosion with fragmentation of the enclosure |
implosion of glass Dewar vessel |
glass fragmentation |
flammable gas (oxygen, hydrogen) |
explosion or fire on exposure to open flame or electric spark |
nonflammable, nonoxygen gas |
asphyxiation |
splattering of liquid or expulsion of small solids placed into a cryogenic fluid |
chemical burns |
freezing with bursting of adjacent water pipes |
flooding, loss of a cooling jacket, leakage of a chemical sink |
change in structure of exposed materials |
materials become brittle or fracture |
where:
• Skin exposed to a metal surface with a cryogenic liquid will adhere to the metal as the surface water freezes. Attempts to remove causes tearing of soft tissues.
• Cryogenic containers have pressure release valves to prevent explosion. These may be obstructed, or an ice plug may form in a narrow necked container.
• Change in material structure may be manifested immediately (placing a cryogenic liquid into an improper container may cause it to leak the cryogenic liquid) or it may be delayed (a flask previously exposed to cryogenic liquid subsequently used to hold concentrated acid).
Specialty: Emergency Medicine, Critical Care