What makes gases flammable?

Not all gases are flammable. eg carbon dioxide, nitrogen or helium. Flammable gases are those which react easily with oxygen in the air to cause combustion... such as hydrogen, methane or propane etc. read more

Gases can be classified into three groups: oxidizers, inert gases and flammable gases. Oxidizers, such as oxygen and chlorine, are not flammable on their own but will act as an oxidant and aid combustion. Inert gases are not combustible at all, and are sometimes used in fire suppression systems. Carbon dioxide and helium are examples of inert gases. read more