Iron and manganese, often present with hydrogen sulfide, turn the water black and greasy-feeling. If untreated, the water stains laundry, washing machines, sinks and kitchenware. When used in the ...

Since the end of November, the San Diego Air Pollution Control District has measured hydrogen sulfide levels above the California safety threshold in the Nestor area more than 15 times.

NASA's Office of the Chief Health and Medical Officer (OCHMO) assembled a small working group to review hydrogen sulfide (H 2 S) Spacecraft Maximum Allowable Concentration (SMAC) values.