Taylor-Wharton High Capacity GST Storage Tanks - Manual (Page 6)

6
SAFETY PRECAUTIONS FOR LIQUID NITROGEN
Nitrogen is an inert, colorless, odorless, and tasteless gas, which makes up four-fifths of the air you
breathe. Liquid nitrogen is obtained by cooling air until it becomes a liquid and then removing the
oxygen, which makes up the other fifth of the air. Liquid nitrogen is at a temperature of 320
degrees below zero Fahrenheit (-196°C) under normal atmospheric pressure.
Extreme Cold - Cover Eyes and Exposed Skin
Accidental contact of liquid nitrogen or cold issuing gas with the skin or eyes may cause a freezing
injury similar to frostbite. Handle the liquid so that it won't splash or spill. Protect your eyes and
cover the skin where the possibility of contact with the liquid, cold pipes and cold equipment, or the
cold gas exists. Safety goggles or a face shield should be worn if liquid ejection or splashing may
occur or cold gas may issue forcefully from equipment. Clean insulated gloves that can be easily
removed and long sleeves are recommended for arm protection. Cuffless trousers should be worn
outside boots or over the shoes to shed spilled liquid.
Keep Equipment Area Well Ventilated
Although nitrogen is non-toxic and non-flammable, it can cause asphyxiation in a confined area
without adequate ventilation. Any atmosphere, which does not contain enough oxygen for
breathing, can cause dizziness, unconsciousness, or even death. Nitrogen being colorless, odorless,
and tasteless cannot be detected by the human senses and will be inhaled normally as if it were air.
Without adequate ventilation, the expanding nitrogen will displace the normal air without warning
that a non-life-supporting atmosphere is present. Store liquid containers outdoors or in other well-
ventilated areas.
Dispose of Waste Liquid Nitrogen Safely
Dispose of waste liquid nitrogen out-of-doors where its cold temperature cannot damage floors or
driveways and where it will evaporate rapidly. An outdoor pit filled with clean sand or gravel will
evaporate liquid nitrogen safely and quickly.
CAUTION: When installing field fabricated piping, make certain a suitable safety valve is
installed in each section of piping between shut-off valves.
For more detailed information concerning safety precautions and safe practices to be
observed when handling cryogenic liquids consult CGA pamphlet P-12 "Handling
Cryogenic Liquids" available from the Compressed Gas Association, 1235 Jefferson Davis
Highway, Arlington, VA 22202.
NOTE: Argon is an inert gas whose physical properties are very similar to those of nitrogen. For handling of
liquid argon, follow the safe practices described for the handling and use of liquid nitrogen.