What to Do If You Smell a Natural-Gas Leak
If natural gas is suspected, leave immediately without operating switches, phones, appliances, vehicles or flames; call 911 and the gas utility only after reaching a safe location.
Timeline
- At the first warning: Do not investigate; alert nearby people verbally and leave by foot without using switches or devices.
- From a safe location: Call 911 and the gas utility, describe the location and follow emergency instructions.
- Before returning: Wait for fire officials or the utility to declare the area safe and do not restore service yourself.
Treat a rotten-egg or sulfur-like gas odor, unexplained hissing or roaring, blowing dust, bubbling water or damaged gas equipment as a possible leak. Most distributed natural gas is odorized to make leaks easier to notice, but smell is not a perfect detector. Do not search for the source or wait to see whether the odor fades. Move people away and begin evacuation immediately. [1][2]
Leave the building or leak area by foot. Do not turn lights, fans or appliances on or off; do not unplug equipment, operate a garage-door opener, start a vehicle or use a phone while still near the suspected gas. Any of those actions can create a spark. Avoid matches, lighters, cigarettes and every other flame or ignition source. Use stairs rather than an electrically operated elevator. [1][2][3]
Once everyone is well away and in a safe location, call 911 and the gas utility's emergency number. Give the address, what you smelled, heard or observed, and whether anyone may still be inside. Follow the dispatcher’s instructions. If the suspected leak is outdoors, remain upwind when possible and keep other people from entering without placing yourself at risk. [1][2]
Do not try to stop the leak, close a pipeline valve, repair an appliance or move damaged equipment. Some local instructions specifically say not to close windows or operate the gas shutoff during an indoor leak because action inside prolongs exposure and may create ignition. Evacuation comes first. Only trained utility or emergency personnel should isolate a suspected leak and decide what equipment requires inspection. [1][2][3]
Do not re-enter because the odor seems weaker, and do not assume that opening a door made the building safe. Wait until the fire department or gas utility gives permission. If service or a meter has been shut off, do not turn it back on yourself. A qualified technician must inspect affected piping and appliances and restore service under the utility’s current procedure. [2][3]
People can also encounter damaged underground lines outdoors. Leave a vapor cloud, pooling liquid, dead vegetation around a pipeline, unusual bubbling or a loud hissing area without touching anything or driving through it. Call 911 and the pipeline operator from far away. Never attempt to extinguish a gas fire unless emergency professionals direct you; escaping gas can remain hazardous even if the visible flame goes out. [1]
This response is for a suspected fuel-gas leak, not carbon monoxide, which has no smell. Homes with fuel-burning appliances also need working carbon-monoxide alarms installed and maintained to current local requirements. Save the utility emergency number before an incident, but in an active leak use it only after leaving. Local fire officials and the serving utility provide the final instructions for the specific system and location. [2][3][4]
Sources
- Pipeline and Hazardous Materials Safety Administration — Pipeline Leak Recognition and What to Do
- Massachusetts Consumer Division — What to Do If You Smell Gas
- U.S. Consumer Product Safety Commission — Gas Appliance Connector Safety
- Centers for Disease Control and Prevention — Carbon Monoxide Poisoning Basics