MVE TEC 3000 Guide De Référence Rapide page 4

Liquid Nitrogen Safety
Liquid nitrogen (LN2) is used in MVE Cryogenic Freezers as a refrigerant. Understanding potential
hazards and following safety precautions is important when handling LN2 and these freezers.
Nitrogen is a colorless, odorless, and tasteless gas that makes up approximately 78.1% of the Earth's
atmosphere in its gaseous state. LN2 becomes vapor at temperatures greater than -320.8°F (-196°C). In
liquid state, nitrogen has a temperature range from -320.4°F to -346°F (-195.8°C to -210°C).
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Recommended protective clothing
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TEC 3000 Quick Reference User Manual
Nitrogen vapor is a potential asphyxiant as it displaces Oxygen (O
confined spaces. Rapid suffocation can occur without warning in an
Oxygen-deficient atmosphere (less than 19.5% O
Freezers must be installed and operated in well-ventilated areas.
DO NOT vent container in confined spaces.
DO NOT enter confined spaces where excess nitrogen gas may be present.
If exposure has occurred move to ventilated area or fresh air. If breathing
is difficult, supplement oxygen may be required. If not breathing, give
artificial respiration. SEEK IMMEDIATE MEDICAL ATTENTION.
Contact with liquid nitrogen or uninsulated equipment containing nitrogen
can result in cold contact burns or tissue damage. Nitrogen vapor can
cause damage to skin or eyes.
In case of frostbite, warm area with warm water not exceeding 105°F (40°C)
and SEEK IMMEDIATE MEDICAL ATTENTION.
Never place LN2 in a sealed container without a pressure relief device. The
expansion ratio of liquid nitrogen to gaseous nitrogen is 1 to 700 (1 cubic
foot of liquid nitrogen becomes 700 cubic feet of gaseous nitrogen when
evaporated).
Cryogenic gloves (loose fitting)
Full-face shield or chemical splash goggles
Cryogenic apron
Long sleeve shirt and cuffless pants
Closed toe shoes (no sandals)
) in
2
). MVE Cryogenic
2