What to do if you smell gas

Leave the building. Call your gas utility or 911 from outside. That is the whole procedure — everything below is detail.

Do

• Get everyone (pets included) out immediately, leaving the door open behind you.
• Call your gas utility's emergency line or 911 once you are away from the building. Utilities respond to gas odor calls 24/7, free.
• If it is safe to do so on your way out and you know where it is, shut the outdoor gas meter valve — only if it is on your path and takes seconds.
• Wait for the all-clear before going back in, even briefly.

Do not

• Do not flip any light switch, on or off. A switch can spark.
• Do not use phones, garage door openers, doorbells, or anything electrical inside.
• Do not light anything, obviously — but also do not start a car in an attached garage.
• Do not open windows to “air it out” while you are still inside; just leave.
• Do not try to find the leak yourself.

A faint whiff at the furnace on first startup of the season?

Dust burning off a heat exchanger after a summer idle smells scorched, not like gas, and clears in under an hour. Rotten-egg odor is the gas odorant (mercaptan) and is never normal. If you are unsure which you are smelling, treat it as gas and make the call — utilities would far rather check a false alarm.