(1)Liquid nitrogen may produce conditions for asphyxiation by displacement of the concentration of oxygen in air below levels necessary to support life.Heat leaks are always present and vaporization takes place continuously.Rate of evaporation varies, depending upon the design of the containers and the volume stored. In general, cryogenic containers have a built-in safety pressure release.
(2)Keep the dust cap on the dewar fill/drain outlet to prevent contamination (dewar flasks are vacuum jacketed, non-pressurized containers).Check the caps to make sure they have not become sealed by frost accumulation.
(1)Liquid nitrogen should only be stored in well-ventilated areas.
(2)which may be too brief to affect the skin of the face or hands, may damage delicate tissues.Extensive tissue damage or burns can result from exposure to liquid nitrogen or cold nitrogen vapors.Flush affected areas with large volumes of tepid water (105-115°F) to reduce freezing.Loosen clothing that may restrict circulation.
(3)Do not apply heat.Frozen tissues are painless and appear waxy with a pallid yellow color.Persons suffering from a lack of oxygen should quickly be moved to areas with normal atmosphere. If the victim is not breathing, assisted ventilation should be initiated.