Liquid Nitrogen Tank Safety Instructions
See your Liquid Nitrogen Supplier for Complete Safety Instructions
Liquid Nitrogen (LN2) which in it's gaseous form makes up 78% of the air we breath is widely used in manufacturing plants, medical facilities, restaurants and on farms and ranches. In it's liquid form it can be dangerous and even deadly. A little care and common sense are required in the safe handling of liquid nitrogen (LN2) and liquid nitrogen storage tanks. Nitrogen gas is odorless, colorless, tasteless ... and it can kill you! LN2 gas is not toxic but it takes the place of the oxygen in the air and can cause suffocation.
Liquid nitrogen is extremely cold at -195°C (-320°F) and when it vaporizes it produces a large amount of very cold gas. These two properties give LN2 the ability to cause serious personal injury and property damage. Never let anything cooled in liquid nitrogen to touch your bare skin because your skin will freeze to it instantaneously and you will pull your skin off when you try to yank the object away. Always wear heavy leather or insulated gloves and goggles (not safety glasses) when working with liquid nitrogen. Always use tongs or forceps to remove straws, canes or other items from the nitrogen storage container. When working with open containers of liquid nitrogen boots should be worn and pants (or a full length apron) should be worn outside the boots to prevent LN2 from running down into your boots. A liquid nitrogen tank must always be stored and used only in an area that is fully ventilated. Never transport tanks in a closed vehicle. Nitrogen gas is extremely cold and your eyes can be damaged by exposure to this gas even when the contact is too brief to freeze the skin. When liquid nitrogen evaporates the cloudy vapor that you see is condensed moisture, not nitrogen gas. The gas itself is invisible.
NEVER OVERFILL THE TANK. Check the liquid nitrogen level in your tanks at least weekly and never allow the liquid nitrogen level in the tank to get lower than 5 inches from the bottom of the tank which is enough to maintain the low temperature in the tank necessary to avoid damage to the material you have stored in the tank. Use a special plastic, solid metal or wooden dipstick to check the nitrogen level. Never use a hollow tube or pipe as the boiling nitrogen will force the LN2 up the tube and into your face. The rate of evaporation and days between refills depends upon the storage conditions (temperature, drafts, sunlight), age and condition of tank and how often you open the tank. Never seal liquid nitrogen tanks with a tight fitting stopper or plug that will not allow the evaporating nitrogen gas to escape or the pressure build up can cause the tank to explode with disastrous results. Only the original necktube stopper that came with the tank should be used. If the tank is covered with frost or condensation the vacuum could be damaged. If damaged, transfer the contents to another tank and remove the damaged one from service.
Store your tank only in a clean, dry, ventilated area. Moisture, caustic cleaners or anything which might cause corrosion should be removed at once. Clean the outside of the tank with plain water or mild detergent solution and then wipe dry. Always store tanks in an upright position to prevent spillage. Tipping them over will causes the liquid nitrogen or nitrogen vapor to spill out and greatly reduces the tank's holding time. Tanks should be handled with extreme care and caution and never dropped or jarred as this can damage the vacuum system. Large tanks are heavy and cannot be easily and safely carried but the optional roller base provides for safe and easy movement in your storage room.
A little common sense and caution go a long way in liquid nitrogen tank safety!