Natural Gas
Asia-Pacific Economic Cooperation (APEC)

European Commission - Eurostat
Natural gas comprises gases, occurring in underground deposits, whether liquefied or gaseous, consisting mainly of methane. It includes both "non-associated" gas originating from fields producing hydrocarbons only in gaseous form, and "associated" gas produced in association with crude oil as well as methane recovered from coal mines (colliery gas) or from coal seams (coal seam gas).

Natural gas does not include biogases and Gas Works Gas. For information, biogases produced by anaerobic digestion of biomass (e.g. municipal or sewage gas) are covered under Renewables and Wastes, while gas works gas production is defined as coal derived products. Transfers of such production to the natural gas network shouldl be reported as inputs from other sources.

International Energy Agency (IEA)
Natural gas comprises gases, occurring in underground deposits, whether liquefied or gaseous, consisting mainly of methane. It includes both "non-associated" gas originating from fields producing hydrocarbons only in gaseous form, and "associated" gas produced in association with crude oil as well as methane recovered from coal mines (colliery gas) or from coal seams (coal seam gas).

Natural gas does not include biogases and Gas Works Gas. For information, biogases produced by anaerobic digestion of biomass (e.g. municipal or sewage gas) are covered under Renewables and Wastes, while gas works gas production is defined as coal derived products. Transfers of such production to the natural gas network shouldl be reported as inputs from other sources.

Latin American Energy Organization (OLADE)
This is a gaseous mixture of hydrocarbons. It includes both free and associated natural gas and is also found in coal mines or zones of geo–pressure. For the purpose of the Energy Balance, both the free and associated net gas produced are considered part of the same source, being of similar nature and use.

Free Natural Gas is a gaseous mixture of hydrocarbons made up primarily of methane obtained from gas fields. Since it generally does not contain condensates, it is commonly called “dry gas”.

Associated Natural Gas is a gaseous mixture of hydrocarbons that is produced in association with crude oil. It generally contains fractions of light liquid hydrocarbons (condensates), so is frequently called “wet gas”.

Organisation of Petroleum Exporting Countries (OPEC)
Gas includes natural gas (excluding natural gas liquids) and gas works gas.

United Nations Economic Commission for Europe (UNECE)
Natural gas comprises gases, occurring in underground deposits, whether liquefied or gaseous, consisting mainly of methane. It includes both "non-associated" gas originating from fields producing hydrocarbons only in gaseous form, and "associated" gas produced in association with crude oil as well as methane recovered from coal mines (colliery gas) or from coal seams (coal seam gas).

Natural gas does not include biogases and Gas Works Gas. For information, biogases produced by anaerobic digestion of biomass (e.g. municipal or sewage gas) are covered under Renewables and Wastes, while gas works gas production is defined as coal derived products. Transfers of such production to the natural gas network shouldl be reported as inputs from other sources.

UNSD Energy Statistics Section
Gases consisting mainly of methane occurring naturally in underground deposits. It includes both non-associated gas (originating from fields producing only hydrocarbons in gaseous form) and associated gas (originating from fields producing both liquid and gaseous hydrocarbons), as well as methane recovered from coal mines.

Production of natural gas refers to dry marketable production, measured after purification and extraction of natural gas liquids and sulphur.

Extraction losses and the amounts that have been reinjected, flared, and vented are excluded from the data on production.

World Energy Council (WEC)
Natural gas is a mixture of hydrocarbon and small quantities of non-hydrocarbons that exists either in the gaseous phase or is in solution in crude oil in natural underground reservoirs, and which is gaseous at atmospheric conditions of pressure and temperature.