Methane, the simplest hydrocarbon, is the primary component of natural gas. The chemical abbreviation for methane is CH4 because a methane molecule contains four hydrogen atoms and one carbon atom. 

Methane is one of the most potent greenhouse gases. And when methane is released in the atmosphere without combustion, it is 20 to 40 times more potent than carbon dioxide (which is created when natural gas is burned). Therefore released methane is a significant environmental concern across the entire natural gas delivery system.