Safety Advisory on Odor Fade in Natural Gas and Propane

March 12 • 2021

The NIOSH Fire Fighter Fatality Investigation and Prevention Program (FFFIPP) has issued a safety advisory on Odor Fade in Natural Gas and Propane.

The advisory addresses an investigation of a line-of-duty death and injuries to six other fire fighters on September 16, 2019, when fire fighters entered a building filled with propane that ignited and exploded. The odor fade of mercaptan was a contributing factor.

Odor fade occurs as leaking natural gas and propane passes underground through soil and concrete, and as it migrates through structures and contacts plywood and drywall. Underwriters Laboratories (UL) and gas suppliers recommend personnel use gas detection equipment to detect natural gas or propane leaks.