Nitrogen is used in many industries, particularly as an inert environment in various chemical and metallurgical processes, for the storage and transportation of easily oxidizable products, in high-temperature metal processing processes that do not interact with nitrogen, for the preservation of sealed metal vessels and pipelines, for filling the free space in mercury thermometers, in the transfer of flammable liquids, and more. Liquid nitrogen finds application in various refrigeration systems.

Mining and Metallurgy:

• for cryogenic annealing and cryoquenching of metals;
• for vacuum degassing of melts;
• as an inert environment for continuous steel casting;
• for cold etching;
• as an energy source in coal mines;
• as an inert environment;
• for filling explosive mines.

Agriculture:

• an inert environment for food storage;
• for storing semen of breeding animals;
• freezing products in field conditions.

Oil Extraction:

• as a safe working agent in the gas lift method of oil extraction and well startup (substitute for compressed air);
• in case of accidents on oil pipelines (freezing of the rupture);
• for extinguishing fires in oil and gas wells;
• for creating ice platforms in open sea or weak soils for drilling.

Machinery and Construction:

• for strengthening steel parts and tools through low-temperature hardening;
• for pressing and deburring parts joined by cold;
• for freezing soils in metro construction, pipelines;
• for freezing and removing tiles;
• deep freezing of mineral raw materials for further fine grinding (e.g., in the production of high-quality cement);
• in the production of tuff coatings.

Chemical and Petrochemical Industries:

• in cryochemistry reactions to obtain high-quality polymers in the production of ethylene, polyethylene, propylene, polyformaldehyde, and more;
• for purifying explosive mixtures of regenerative catalysts;
• for storage and transportation of easily flammable liquids.

Food Industry:

• for freezing, transportation, and storage of food products.

Medicine:

• for preserving blood and blood transfusion products;
• for rapid freezing and storage of tissues and various organs;
• in the production of full-fledged powdered pharmaceutical preparations.

• Accumulation of gaseous nitrogen causes oxygen deficiency and suffocation. The oxygen content in the working area must be at least 19% (by volume).
• Liquid nitrogen is a low-boiling liquid that can cause skin frostbite and damage to the eye mucous membrane. When handling samples of liquid nitrogen, protective goggles must be worn.
• When the oxygen content in liquid nitrogen is increased to 30% (by volume) (for example, due to evaporation of liquid nitrogen), the formation of flammable and explosive mixtures with organic substances is possible. Therefore, the presence of oils, organic solvents, and other flammable or explosive substances in baths or other open vessels intended for work in a liquid nitrogen environment is unacceptable. Before using and performing work involving liquid nitrogen, the oxygen content in it must be checked. The drainage of liquid nitrogen should be carried out in specially designated areas without asphalt, wood, or other organic materials.
• Prior to conducting repairs or inspections of a transportable or stationary liquid nitrogen container that has been in use, it must be warmed up to ambient temperature and purged with air. Work can only be started after the oxygen content inside the tank and equipment is at least 19% (by volume).
• When working in an atmosphere with nitrogen, it is necessary to use an isolating oxygen apparatus or a hose mask.