Canadian Occupational Safety

damage on contact. When handling the substance, workers — including servers and bartenders — should be wearing loose-fi tting insulated (cryo- genic) or leather gloves, goggles and a face shield, long-sleeved shirt, pants without cuffs and closed-toe shoes, says the Ontario Ministry of Labour. Tremendous force can be created if liquid nitrogen vaporizes in an enclosed space. For example, a canis- ter of the liquid with a failed pressure valve can be propelled with enough force to shatter a reinforced concrete beam, says WorkSafeBC. Proper con- tainers designed for liquid nitrogen storage and proper transfer equipment are a must. If there is a large spill or a container ruptures, the building should be evacuated because there may be an oxygen defi ciency. Nitrogen gas is capable of displac- ing oxygen in the air, which can lead to dizziness, nausea, vomiting or death. An oxygen monitoring system should be provided in areas where liquid nitrogen is stored and used, says the Ontario Ministry of Labour. All restaurants that are using liquid nitrogen need a standard operating pro- cedure for handling and using it safely, as well as an emergency procedure on what to do if it comes in contact with the body, says Jones. Cold burns should be fl ushed with tepid water or placed in a warm water bath. The skin should not be rubbed as this may cause tissue damage, and the victim should seek medical attention. Although liquid nitrogen is colour- less, odourless and tasteless, it can still pose hazards if ingested. Three years ago in Miami, a 61-year-old woman spent fi ve days in the hospital after taking one sip from her cock- tail that left holes in her esophagus and stomach. Consumers — includ- ing excited chefs and staff — need to wait until liquid nitrogen wears off completely before taking a bite or sip of the concoction. The use of liquid nitrogen falls under the Workplace Hazardous Mate- rials Information System (WHMIS) and there should be a safety data sheet available for it. Restaurant workers should have WHMIS training to make sure they not only know how to work with liquid nitrogen, but also with the many different chemicals used in food service, such as sanitizers, soaps, oven cleaners, deep fryer cleaners, degreas- ers and fl oor cleansers. "It's important to have that training aspect so the workers know what those products are and what they're used for and that they are mixing them and using them at those proper concen- trations," says Rosalyn Sellick, OHS offi cer at the Workers Compensation Board of PEI in Charlottetown. Liquid nitrogen is not the only up and coming concern in the res- taurant and food service industry. 24-year-old German chef blew off both of his hands when experimenting with liquid nitrogen. He was testing out a new "molec- ular gastronomy" recipe when there was an enormous explo- sion. The chef lost his right hand in the explosion and his left hand had to be amputated at the hospital, said German media when the incident occurred in July 2009. He also suf- fered a serious injury on his leg and genital area. Liquid nitrogen is being used more and more in restaurants, ice cream parlours, bars, concession stands and catering services for its ability to cause instant freezing — it has a boil- ing point of -196C — and create a visible fog, enhancing the entertain- ment factor for customers. The liquid expands rapidly at room temperature to nitrogen gas (1 litre of liquid nitro- gen produces 70 litres of nitrogen gas). Cocktails are given a mystical quality, ice cream goes from mere ingredients to a smooth, frozen treat in seconds and popcorn gets a fun twist by being served cold. Liquid nitrogen can even freeze alcohol, allowing bartenders to make extremely cold drinks, cocktail slushies or alco- holic ice cubes. Behind the scenes, chefs are using it to freeze ingredients, such as choco- late, berries, citrus, herbs and honey. They become very cold and brittle after being blasted with liquid nitro- gen, and they can even be crushed into a powder. While it can be fun for chefs and patrons alike, liquid nitrogen comes with many hazards that restaurant and food ser vice employers and workers need to understand. Both the Ontario Ministry of Labour and WorkSafeBC came out with hazard alerts specifi cally for liquid nitrogen over the past seven months due to increased use in the restaurant and food service industry. "Improper handling, if it gets in your eye, could cause blindness. If it gets on your skin, it could cause skin damage. It kills the skin, blistering, and in large quantities it could be quite harmful," says Ken Jones, certifi ed food safety specialist with Keel HSE Management in Dartmouth, N.S. "You compare it to hot oil, a deep fat fryer for example, they are pretty much on different ends of the spectrum from being 196C hot and -196C cold and equally they will do the same amount of damage." Liquid nitrogen can cause cold burns, frostbite or eye Restaurant, food service industry must consider risks with emerging food trends, poor mental health, young worker safety By Amanda Silliker

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