gas cookers gas cooking gas cooled gas cooler gas cooling gas coordination gas corporation gas cost gas costs gas crisis gas customers gas cutting gas cylinder gas cylinder valve gas cylinders gas data gas day gas deal gas delivered gas delivery gas delivery system gas demand gas density gas deposits gas desulfurization gas detection gas detector gas detectors gas development gas did gas diffuser gas diffusion gas diffusion layer gas directive gas discharge gas discharge lamp gas discharge lamps gas discharge tube gas discoveries gas discovery gas dispersion gas dispute gas dissolved gas distribution gas distribution company gas distribution network gas distribution system gas distributor gas division gas do gas does gas drilling gas dryer gas duct gas dynamics gas electric gas emission gas emission allowance gas emission reductions gas emissions gas emissions will gas emitted gas energy gas engine gas engines gas entering gas enters gas environment gas equipment gas escapes gas escaping gas evacuation gas evolution gas evolved gas exchange gas exhaust gas exit gas exits gas expansion gas exploitation gas exploration gas explosion gas explosions gas export gas exporter gas exporting gas exports gas exposure gas extraction gas facilities gas facility gas factory gas feed gas field gas fields gas filled gas filling gas filter gas filtration