I Smell Gas — What to Do Right Now
If you smell gas in your home, act first and investigate later. Here are the exact steps to take immediately to stay safe, who to call, and what never to do until the gas company says it's clear.
A natural-gas or propane leak is one of the few home emergencies where the right move is to act first and investigate later. Gas is explosive, and the time you'd spend looking for the source is time better spent getting to safety. Read this once now, so you already know what to do.
Quick answer: If you smell gas, get everyone out first — don't touch any light switch, appliance, flame, or phone, because a single spark can ignite it. Leave the door open behind you, and once you're safely outside and away from the house, call 911 and your gas company. Don't go back in until they say it's safe.
If you smell gas right now, do this
Get out first. Everything else can wait.
- Don't touch anything electrical or any flame. No light switches, no appliances, no thermostat, no garage-door opener, no matches or lighters. A single spark can ignite gas.
- Get everyone out — people and pets — and leave the door open behind you so gas can escape.
- Don't use your phone inside. A phone can be an ignition source. Wait until you're well away from the building.
- Call for help from outside. From a safe distance, call your gas utility's emergency line and 911.
- Shut off the gas only if it's safe and on your way out. If you can reach the main gas shutoff valve safely and know how, turn it off — but never go back inside or into danger to do it.
Do not try to find the leak, ventilate the house, or fix anything yourself. Let the gas company verify it's safe before anyone goes back in.
How to recognize a gas leak
Natural gas and propane are odorless on their own, so utilities add a chemical called mercaptan that smells like rotten eggs or sulfur. That smell is your warning. Other signs:
- A hissing or whistling sound near a gas line, meter, or appliance.
- A blowing dust cloud or bubbling in standing water near an outdoor gas line.
- Dead or dying vegetation in a patch over a buried line.
- Feeling dizzy, nauseous, or lightheaded indoors with no other explanation.
Gas leak vs. carbon monoxide — they're different dangers
It's worth knowing these are two separate hazards:
- A gas leak is unburned fuel escaping. You can usually smell it (rotten eggs), and the danger is explosion.
- Carbon monoxide (CO) is a byproduct of burning fuel. It's completely odorless and invisible, and the danger is poisoning. The only way to detect it is a working CO alarm.
That's why a working CO alarm matters so much — and why it's a core safety task to test your smoke and CO alarms and replace any alarm older than 10 years. If a CO alarm sounds, treat it the same way: get everyone to fresh air and call for help.
After the gas company clears it
Once the utility has found and stopped the leak and declared the home safe:
- Have a qualified technician repair the source before relying on the appliance again.
- If the leak was at a water heater, furnace, or stove pilot light, have the pilot and gas valve checked.
- Confirm your smoke and CO alarms are working — a gas event is a good reminder to test them all.
The best time to prepare is before
In a real gas emergency you won't be reading instructions — you'll be acting on what you already know. Make sure every adult knows where the main gas shutoff is and how the alarms work. Build your free Owner Tools plan and we'll keep alarm tests and safety checks on your schedule. No login, no address required.