Leave the building now. Take everyone with you. Do not turn anything on or off on the way out, including a light switch, an extractor fan, an appliance or a phone. Call your gas utility's emergency line, or 911, from outside, from a neighbor's phone or from a mobile once you are well away from the building.
That is the whole of the correct action. Everything below explains why each part of it is worded that way.
There is no repair instruction anywhere on this page and there is not going to be one. Not a soap test, not a valve check, not a burner adjustment, not a fitting to tighten. A gas leak in a home is not a homeowner job at any stage, and an article that gives you a step to try first is asking you to spend time inside a building that you should be leaving.
Why the electrical rule is worded so strictly
The reason for "do not touch a switch" is that a switch makes a small spark as it opens or closes, and a spark is an ignition source.
CPSC's public safety guidance is consistent on this: if you smell gas, leave immediately and contact the gas authorities from outside, and do not operate any electronics such as lights or phones before leaving. Its wording elsewhere is more explicit still: do not light a match, turn on a light, or switch on anything electrical.
Which means all of the following are on the do-not list, on the way out:
- Light switches, in either direction. Turning a light off is the same action as turning it on.
- The extractor fan or range hood, which people reach for instinctively to clear the smell.
- Doorbells, garage door openers and thermostats.
- A phone, until you are outside and away.
- Anything with a plug, and the plug itself.
Open a window on your way past if it is already easy to reach, and do not go looking for windows to open. Ventilation is useful and it is not worth staying inside for.
Why the phone call happens outside
Two reasons, and the second one is the practical one.
A phone is an electrical device. That is the ignition argument.
And you need to be out anyway. Making the call from outside means you have already done the important part before you start explaining anything to anybody.
Who to call: your gas utility's emergency number, which is on your bill and is usually staffed around the clock, or 911. If you are on propane rather than piped gas, your supplier has an emergency number too.
Do not go back in to fetch anything, to check anything or to reassure yourself. Wait for the people you called.
What a stove gas smell can be, and why it does not change the answer
There are less serious explanations. A burner knob nudged and left slightly open. A pilot light out on an older appliance. A brief smell when a burner is lit.
None of them changes what you should do, because a homeowner cannot tell them apart from a leak by smell, and the cost of being wrong is not comparable to the cost of an unnecessary call out.
Utilities and fire services expect these calls. Making one that turns out to be nothing is a normal event and it is what the emergency line exists for.
The smell itself
Natural gas and propane have no smell of their own. An odorant is added specifically so that leaks can be detected by people, and it is usually described as rotten eggs or sulfur.
Two consequences worth knowing.
Some people cannot smell it, whether through a temporary illness, a long-term loss of smell, or because a strong smell has been present long enough to stop being noticed. That is one of the arguments for a fuel gas alarm, which is a separate device from a smoke alarm and from a carbon monoxide alarm.
A faint, intermittent smell is still a call. People wait for it to get stronger, and getting stronger is not information you want to collect from inside the building.
Gas smell and carbon monoxide are different problems
They are often confused and they need separating.
A gas smell is unburned fuel, and the risk is fire and explosion.
Carbon monoxide is a product of incomplete combustion. It has no smell at all, and no odorant is added to it because it is not something anybody supplies deliberately. A CO alarm is the only way to detect it.
Symptoms of CO exposure, such as headache, dizziness, nausea and confusion in more than one person in the household at once, are a leave-the-building situation of their own, with a call to 911 and to your utility, and with medical attention for anyone affected.
Neither of these is something to investigate. Both are leave and call.
What to do afterwards
Whatever the utility or the fire service tells you. That instruction supersedes anything on this page.
If a technician says the appliance is unsafe, do not use it. Not once, not carefully, not until the part arrives.
Any subsequent work on a gas appliance or a gas line is a licensed gas professional's, and in most places it is regulated work rather than a matter of preference. This site publishes no gas repair instruction of any kind, on any page, and will not.
The things that make this less likely, done at a calm moment
None of these is a substitute for the response above.
Know where your gas shutoff is, and know that operating it is something you do on instruction rather than on initiative. Knowing where it is costs nothing and is worth doing before you ever need it.
Have working alarms. A carbon monoxide alarm is standard and in many places is required. A fuel gas alarm is a separate device and exists.
Have the utility's emergency number saved outside the house, in a phone contact list rather than only on a bill on the kitchen counter.
Keep the appliance serviced on the manufacturer's schedule, which is in the manual, by someone qualified for gas work.
Keep burners and the cooktop clean, which is ordinary maintenance rather than safety work, and is covered in how to clean gas stove burners and how to clean a glass cooktop.
FAQ
What should I do if I smell gas in the kitchen? Leave the building with everyone in it, without operating any switch, appliance or phone on the way out, and call your gas utility's emergency line or 911 from outside.
Can I turn on the extractor fan to clear it? No. A switch is an ignition source. CPSC's guidance is not to operate any electronics before leaving, including lights and phones, and the fan is the one people reach for most often.
Can I use my phone inside to make the call? No. Make the call from outside, from a neighbor's phone or from your own once you are away from the building.
What if it is only a faint smell? Treat it the same way. A homeowner cannot distinguish a small leak from a large one by smell, and waiting for it to strengthen means waiting inside.
Is it worth calling if it turns out to be nothing? Yes. Utilities and fire services expect these calls and the emergency line exists for exactly this. An unnecessary call out is not comparable to the alternative.
Is a gas smell the same as carbon monoxide? No. A gas smell is unburned fuel, detectable because an odorant is added, and the risk is fire and explosion. Carbon monoxide has no smell and is only detectable with an alarm. Both are leave-and-call situations rather than things to investigate.
Sources: Consumer Product Safety Commission public safety guidance on gas leaks, checked 2026-08-28: leave immediately and contact local gas authorities from outside the home, do not operate any electronics such as lights or phones before leaving, and do not light a match, turn on a light or switch on anything electrical. Our fetcher received an HTTP 403 from cpsc.gov on that date, so this guidance is reported from CPSC's own indexed safety pages rather than from a page we opened directly, and is labeled as such rather than presented as a verbatim quotation. That is our retrieval failing, not anything on CPSC's side, and a writer with working access should replace this note with a direct read before publish.
No repair step, diagnostic test, adjustment, part or gas figure appears anywhere on this page, by design. Any work on a gas appliance or a gas line is a licensed gas professional's, and this site publishes no gas repair instruction.
