Liquid Nitrogen
Background:
Liquid nitrogen is nitrogen in a liquid state at a very low temperature. Some bars are using liquid nitrogen to chill glassware, for "cryo-muddling" of ingredients, and other purposes. Liquid nitrogen can cause severe burns/frostbite, asphyxiation, or explosions if not handled properly. It is very important that all people working with- and even near- liquid nitrogen be fully trained on safe handling, use, and storage.
In one case, a woman was served a drink with liquid nitrogen in it, resulting in her needing her stomach removed [link]. In another case, liquid nitrogen was poured into a pool and caused several people to lose consciousness as the gas replaced oxygen above the surface of the water [link].
Safety Information:
The information on this website is not a substitute for proper training in liquid nitrogen handling. Below are some guidelines to inspire that training before using liquid nitrogen.
- Liquid nitrogen must be stored and handled in a vented, pressure relief, or unsealed container to ensure it does not cause an explosion.
- Liquid nitrogen can cause oxygen buildup in its immediate area, which can result in fire hazards of typically non-flammable materials including clothing. Liquid nitrogen should be handled and stored in a well-ventilated area for this reason and also:
- Liquid nitrogen can displace oxygen, and as it is colorless and odorless it can cause asphyxiation without warning signs. Liquid nitrogen should be handled and stored in a well-ventilated area.
- Wear appropriate protective clothing when handling liquid nitrogen, including approved safety gloves and protective eyewear. Gloves should be loose-fitting so that they can be quickly removed in case liquid nitrogen gets into or on them.
- Particularly when transferring liquid nitrogen, avoid splashing and splattering. Splashing can more readily occur when transferring the liquid from a larger tank to a dewar (vacuum flask), or moving the dewar, or from a tank to a warmer dewar) .
- Use only approved dewars (vacuum flasks) for handling. Other containers can crack or explode. Never store liquid nitrogen in any sealed container as explosions can quickly result. Do not use a coffee thermos to hold liquid nitrogen.
- Do not touch without protective equipment any non-insulated equipment/containers/etc that have held liquid nitrogen.
- Do not put a hollow tube into liquid nitrogen, as these can cause liquid to spurt.
Further Reading:
"A British Woman Had to Have Her Stomach Removed After Drinking This Cocktail" Vice [link]
"Watch as this liquid nitrogen pool party goes horribly wrong" i09 [link]
"Liquid Nitrogen" Wikipedia [link]
"Financial analyst, 35, sues George Clooney, Rande Gerber, their former tequila company and the Beverly Hilton claiming a bartender at the swanky hotel gave him a liquid nitrogen-laced shot that made him 'collapse in agony'" [link]
"Woman Had to Have Gallbladder Removed After Waiter Poured Liquid Nitrogen in Her Drink" [link]
Safety and Handling Information Used for this Post:
https://ehs.research.uiowa.edu/liquid-nitrogen-handling
https://engineering.dartmouth.edu/microeng/ln2.html
https://www.tedpella.com/cryo-supplies_html/HandlingLiquidNitrogen.htm
(This one is particularly detailed) https://www.ars.usda.gov/northeast-area/docs/safety-health-and-environmental-training/liquid-nitrogen-safety/