Hydrogen sulfide is a naturally occurring flammable, colorless gas with a characteristic odor of rotten eggs. It is produced by bacterial breakdown of organic matter as well as human and animal wastes. People can smell it at low levels. For more information on H2S, please visit www.atsdr.cdc.gov/toxfaqs/tf.asp?id=388&tid=67.
All values for hydrogen sulfide have been “non-detect.” A non-detect means that concentrations are lower than the sampling equipment can detect. The minimum detection level (MDL) for hydrogen sulfide on the portable monitor is 1 part per million (ppm).