"Hydrogen sulfide has been responsible for the death of many people worldwide, including many cases where people have been overcome attempting to rescue colleagues."

Bureau of Labor Statistics (BLS) indicate H2S caused 60 worker deaths between 2001 and 2010.

It is highly flammable and toxic, even at low concentrations. It is heavier than air and may travel along the ground.

Watch H2S Movie Trailer: http://www.ask-ehs.com/safety-training/h2s/