Gas is an aggregate state that is neither solid nor liquid, but the substance exists as a gas. Gases include natural gas, hydrogen, nitrogen, oxygen, CO2 and other chemical substances.

Gases are used in a wide range of industries including energy, chemistry, transportation and food. Natural gas, for example, is used as a fuel for heating and electricity generation, while nitrogen and oxygen are used in food packaging to ensure freshness, and CO2 is used in the production of soft drinks.

The quality of gas is important and determined by properties such as composition, pressure, temperature and purity. Regulation and control of gas production and processing are necessary to ensure quality and safety. Regulation and control of gas production and processing are necessary to ensure quality and safety. Since gases can be stored in large quantities and are transportable, it is important to ensure a safe and efficient infrastructure for gas production, storage and shipping.