Where can you buy liquid nitrogen? Your local welding supply should have LN2, or an industrial gas supplier. You must use the proper dewar to transport the liquid nitrogen. A dewar is different from a thermos because it is designed to handle the extremely cold liquid nitrogen temperature (-196 deg C, -321 deg F) without cracking. Dewars are designed to vent which is extremely important. As liquid nitrogen expands from the liquid to the gas stage it will build up tremendous forces if not allowed to vent and an explosion could occur. LN2 has been more and more a part of the culinary world and more people who do not generally work with it are using it. In addition to the danger of explosion, a user will get burns if they come in contact with the liquid nitrogen. Purveyors of LN2 will not release it to customers without the proper container. However with the proper container there is no restrictions on buying liquid nitrogen. Liquid nitrogen is used in cocktails because it is cold enough to freeze ethanol which has a lower freezing point than water. LN2 is also handy for making ice cream almost instantly.