In the home, exposure may occur because of faulty plumbing. Sewer drains that have dry traps can allow hydrogen sulfide gas to enter the home. Another common exposure is from well water that contains hydrogen sulfide gas. The unpleasant odor of well water does not usually signify a health hazard because the smell of hydrogen sulfide gas can be detected at low levels. Workers involved in occupations such as livestock farming, sewage treatment, and oil refining may be exposed to hydrogen sulfide gas at work.
Some people can smell it at even lower levels.
Exposure to higher levels of hydrogen sulfide gas can irritate the eyes, the nose, and the lungs. Although hydrogen sulfide gas has a strong odor, extended exposure deadens the sense of smell. At this level, you should not rely on your sense of smell to decide if hydrogen sulfide gas is present. An instrument that measures hydrogen sulfide gas in air should be used. As hydrogen sulfide gas levels increase, the gas can cause eye irritation, dizziness, coughing, and headache.