Which type of gas is often measured for in sewer inspections?

In sewer inspections, measuring hydrogen sulfide gas is crucial due to its potential to pose serious health risks. This gas is a byproduct of the decomposition of organic matter in the absence of oxygen, which is common in sewer environments. Hydrogen sulfide is notorious for its foul odor, resembling that of rotten eggs, and can be dangerous even in low concentrations, leading to irritation of the eyes, nose, throat, and, at higher levels, can result in more severe health effects or even fatality.

Monitoring this gas is an essential safety precaution for workers involved in sewer inspections and maintenance, as it helps to ensure their protection from exposure. While other gases like carbon monoxide and methane can also be relevant in certain contexts, hydrogen sulfide is particularly linked to the anaerobic processes occurring in sewer systems, making it a primary focus during inspections.