Nitrogen, carbon dioxide, argon and mixtures of these gases are inert and prevent the formation of explosive or oxidizing atmospheres.
Carbon dioxide, argon and their mixtures are employed for fire fighting when water cannot be used.
Nitrogen and carbon dioxide are used to inert grain silos.
Liquid nitrogen is employed for ground freezing, partial freezing of liquids in pipelines for repairs and as emergency cooling.
Nitrogen is used for safety inerting and pressure build up in the recovery of oil and gas wells.