Detection — three senses

Propane is odorized with ethyl mercaptan, which smells like rotten eggs or skunk. Beyond smell, watch for:

  • Sound — hissing or whistling at valves, regulators, fittings
  • Sight — frost on a regulator, dead vegetation near buried lines, soap-bubble test at suspect joints
  • UL-listed electronic detectors mounted low to the ground (propane pools low)

If you suspect a leak — three steps

  1. LEAVE the building immediately — get everyone outside
  2. SHUT OFF the tank service valve if it's safe to reach without re-entering
  3. CALL the dealer's emergency line and the fire department from outside

What NOT to do

  • Do not operate any electrical switch
  • Do not use phones, doorbells, garage doors inside
  • Do not light matches, lighters, or relight pilot lights
  • Do not try to find the leak yourself
  • Do not re-enter until a licensed technician confirms it's safe

Prevention

Annual professional inspection catches most leak sources before they become emergencies. Replace aging regulators (15–25 year service life). Maintain clear ground around the tank. Educate every household member on the smell of propane and the LEAVE-SHUT-CALL procedure.

FAQ

What does a propane leak smell like?

Rotten eggs, skunk, or decaying matter — the smell of ethyl mercaptan added to propane as an odorant. Most dealers provide a 'scratch and sniff' card so household members can familiarize themselves with the exact smell.

How much does fixing a propane leak cost?

Depends on the source. A regulator replacement: $200–$500. A fitting tightening or replacement: $75–$200. Service-line replacement: $500–$2,000+. The leak test itself: $50–$150.

Going further