Damage Controlman (DC) A-School Test 2 Practice

Rotten-egg odor is the telltale sign of hydrogen sulfide. This gas forms when sulfur compounds decompose, especially in anaerobic conditions such as sewage, manure, or some industrial processes. Hydrogen sulfide is a colorless, heavier-than-air gas that is highly toxic, so the smell can be a crucial warning, though at higher exposures the sense of smell can be impaired. Other common gases have different smells or none at all: ammonia has a sharp, pungent odor; sulfur dioxide has a sharp, irritant odor; methane is odorless unless an odorant is added for leak detection. So the gas associated with rotten eggs is hydrogen sulfide.