At room temperature and atmospheric pressure, nitrogen is a colorless, odorless, nontoxic, nonflammable gas. It constitutes 78% by volume of the atmosphere. Naturall occurring nitrogen contains two isotopes, 14N and 15N, with a relative abundance of 99.62% and .38%, respectively.
Nitrogen is used as an inert gas in electrical systems, the chemical industry, and in the food packaging industry. Nitrogen also finds extensive use as an inert atmosphere, and in the filling of some incandescent lamps.
Large quantities of nitrogen are produced by the liquefaction and fractionation of air.
Nitrogen gas is authorized for shipment in cylinders, tube tank cars and tube trailers. Liquid nitrogen is shipped as a cryogenic fluid in vacuum insulated cylinders, and in insulated portable tanks, tank trucks and tank cars.