As modernist cuisine has become more popular, restaurant and home chefs alike are turning to liquid nitrogen to create spheres, gels, foams, and even ice cream. While liquid nitrogen can be safely used in a range of culinary applications, there are important safety risks to be aware of when working with this substance.
The Hidden Dangers of Liquid Nitrogen in the Kitchen
Nitrogen can help chefs freeze alcohol, which doesn't freeze under freezer temperatures. Nitrogen also creates a very rich ice cream, since it makes superfine ice crystals. By using liquid nitrogen to freeze foods, chefs can keep more flavor in the food and preserve higher amounts of the food's nutrients.
It's important to note that nitrogen is used only to alter the state of food. The nitrogen itself is not consumed.
While it is no wonder that nitrogen has become so popular in the kitchen, the substance can pose a health hazard.
Liquid nitrogen is extremely cold. If the substance were to spill on your clothing or get in your eyes, it could cause severe burns. Thus, many culinary workers wear an extra layer of clothing (such as an apron) to prevent nitrogen from causing skin burns. Special gloves protect the hands, and safety goggles prevent the eyes from nitrogen burns.
While many are aware of the burn danger from liquid nitrogen, there is a more insidious hazard. When liquid nitrogen meets the air, it starts to evaporate and turns into nitrogen gas. Nitrogen gas is a known oxygen displacer, so the more gas that escapes, the less oxygen the air has. Quickly, nitrogen gas can deplete the air to low enough levels of oxygen that respiratory problems and death via asphyxiation are cause for concern. While you may see the smoke or fog from liquid nitrogen, actual nitrogen gas has no color or odor. Thus, if you miss the fog of liquid nitrogen, you may not know the atmosphere is oxygen deficient until it is too late.
The human brain requires a continual supply of oxygen to work properly. Without this steady oxygen supply, the brain begins to shut down. Confusion and mental fog occur, along with symptoms of respiratory distress, including nausea and vomiting. Due to the severity of these symptoms, an individual in an oxygen-deficient environment has little chance of rescuing themselves before dying.
How an Oxygen Monitor Protects Safety
If you plan to use liquid nitrogen, take the necessary precautions to protect skin and eyes from burns. Then take the extra step to install an oxygen deficiency monitor or oxygen analyzer.
The oxygen deficiency monitor mounts on the wall in the area where nitrogen is stored and used. The device constantly checks the levels of oxygen in the air. As long as the air is safe to breathe, the monitor remains silent yet alert. If liquid nitrogen evaporates and begins displacing oxygen, the O2 monitor tracks the falling levels. Should oxygen drop such that the air is no longer safe to breathe, the O2 monitor will flash a visual and audio alert telling staff to get out of the kitchen.
The monitors are designed to alert when oxygen levels fall below the limits set by OSHA of 19.5 percent. When oxygen levels are between 19.5 and 15 percent, symptoms of oxygen deficiency begin to occur. Health hazards arise when levels fall below 6 percent. So, the analyzer gives staff enough time to safely evacuate and avoid a health risk.
If you want to use nitrogen in the kitchen, while reducing the safety risks for your kitchen staff, invest in an oxygen monitor. Oxygen monitors from PureAire come with hardy zirconium oxide sensors, which require no maintenance and have a 10-year life span. They are an effective, efficient way to circumvent nitrogen's hidden dangers. See PureAire's line of oxygen monitors and oxygen analyzers at www.pureairemonitoring.com