You may be familiar with the distinctive odor of natural gas from the additive mercaptan, which smells like sulfur or rotten eggs. This odor is the most common indicator of an indoor gas leak.

A roaring, blowing, or hissing sound is another indicator and means that gas is escaping under pressure from a damaged pipe, a compromised connection, or a leaking gas appliance.

However, a natural gas leak may exist in the absence of these warning signs. This makes air monitoring essential for confirming gas concentrations in buildings where a leak is suspected.