Safety guide · Ellicott City, MD
Signs of a Gas Leak in Your House and What to Do
If you smell gas or think there is a leak, the plan is short: get out, stay out, and call from outside. This guide covers what a leak looks, sounds and smells like, and what happens after you are safe.
Emergency? Call now, 24/7(443) 981-2600- Leave the buildingWalk out right away, and bring everyone and every pet who can come with you.
- Call from outsideUse the gas utility emergency line or 911 once you are away from the house.
- Stay out until clearedDo not go back in until the utility or fire crew says the house is clear.
Signs of a gas leak in your house: the short version
- A rotten-egg or sulfur smellUtilities add a strong odor to natural gas so leaks are noticeable. Treat any such smell as real.
- A hissing, whistling or blowing soundNear a gas line, meter or appliance, this can mean gas is escaping under pressure.
- Physical signsHeadache, dizziness, nausea or a feeling of being unwell that eases when you go outside.
- Outdoor cluesDead patches in an otherwise green lawn along a line, bubbles in standing water, or dust blowing from a hole.
- What to doLeave first. Call your gas utility or 911 from outside. Do not look for the source yourself.
If you suspect a leak: the sequence that keeps you safe
Do not stop to investigate, open a window or finish what you were doing. The order matters, and every step is about getting distance between people and the gas.
Leave, then call
Walk out calmly and take anyone in the home with you. Do not use a light switch, doorbell, garage door opener, or phone charger on the way. Small sparks can ignite gas in the air. Do not start a car parked in an attached garage.
From outside and some distance from the house, call the gas utility’s emergency number, which is printed on your bill, or call 911. Say you smell gas. Then wait where responders can find you. Do not go back in for pets or belongings. Tell the crew if anyone was left inside.
Get everyone out
Do not search for the source or open windows.
Avoid sparks
No light switches, no lighters, no electronics on the way out.
Call from outside
Gas utility emergency line or 911, from a safe distance.
Wait for clearance
Re-enter only when the utility or fire crew says so.
Do not try to fix a gas leak yourself
No homeowner steps are listed on this page for stopping gas, on purpose. Do not relight a pilot, tighten a fitting or turn valves while you suspect a leak. Leave the building and let the utility and a qualified plumber handle it.
Signs of a gas leak in your house, sense by sense
A leak can be loud, quiet or nearly invisible. Learn the clues, because the earliest ones are easy to dismiss.
| Sense | What to notice | Notes |
|---|---|---|
| Smell | Rotten eggs, sulfur, or a skunk-like odor. | Odor can be faint near a small leak, or can fade as you grow used to it. A fresh nose from outdoors helps. |
| Hearing | Hissing, whistling or a thin blowing sound near a pipe, meter or appliance. | Often more noticeable when the house is quiet. |
| Sight | A white mist or cloud near an outdoor line, a damaged line connected to an appliance, or dirt blowing from a spot in the ground. | Rarely visible indoors. |
| Body | Headache, nausea, dizziness, fatigue or watery eyes that ease outdoors. | Same symptoms can come from carbon monoxide, which has no smell. |
| Pets and plants | Pets behaving oddly, houseplants wilting for no clear reason. | Weak clue on its own, but it supports other signs. |
Parts of a home where gas leaks tend to start
Knowing the likely spots helps you describe the problem to the dispatcher, without trying to inspect anything yourself.
Common starting points
Leaks tend to start at joints and connections, not in the middle of straight pipe. Flexible appliance connectors can crack or loosen when a stove or dryer is pushed back against the wall. Older fittings can dry out and seep at threaded joints. Outdoors, a damaged line can result from digging near a buried gas line.
If you suspect an appliance, gas leak repair covers what a plumber looks at once it is safe. For a failing run of pipe, gas line repair explains line work. Do not inspect these spots yourself before the utility has cleared the house.
- Range and ovenThe flexible connector behind the unit and the shutoff valve.
- DryerThe connector on the back, easily bent when the dryer is moved.
- Water heaterGas supply to the burner area and the vent path.
- Furnace or boilerSupply fitting, drip leg and unions.
- Meter and outdoor lineFittings at the regulator and any exposed line.
Gas leak versus carbon monoxide: not the same problem
People mix the two up, and the difference changes how you respond. Both are emergencies.
| Natural gas or propane leak | Carbon monoxide | |
|---|---|---|
| Odor | Added on purpose, smells like rotten eggs | No smell at all |
| Cause | Gas escaping from a pipe or appliance | Incomplete burning in a furnace, water heater, stove, fireplace or vehicle |
| Warning device | Gas detector, your nose | CO alarm |
| Main hazard | Fire or explosion, plus oxygen displacement in a closed space | Poisoning |
| Response | Leave, call utility or 911 from outside | Leave, call 911, stay outside |
What happens after you call
Knowing the usual sequence takes some of the stress out of a very stressful moment.
From arrival to all-clear
Crews arrive with meters that read gas in the air. They check the house and may find and shut off the supply at the meter. If a leak is found inside the home, the gas may stay off until a plumber repairs it and the line is tested.
You can then call for repairs. A plumber checks the suspect appliance or pipe, repairs or replaces the part, and confirms the work holds. If appliances were turned off, a 24/7 emergency plumber can help when you need service the same day. Questions about whether the utility or the plumber relights equipment are best asked on the call.
Utility or fire crew checks
Meters read gas levels room by room.
Supply may be shut off
Gas can stay off until the problem is fixed.
Plumber repairs the cause
Pipe, connector or appliance fitting repaired and tested.
Service restored
Done by the people with authority to turn it back on.
Natural gas and propane: the same rule, different behavior
Most homes in a suburban setting use piped natural gas, but some use bottled or tank propane. Both need the same response. Their behavior in a building differs a little, which helps explain where a smell is strongest.
| Detail | Natural gas | Propane |
|---|---|---|
| Weight compared with air | Lighter, tends to rise and collect near ceilings | Heavier, tends to sink and pool in low spots such as basements |
| Where it comes from | Utility pipe, meter at the property | A tank or cylinder on or near the property |
| Who to call first | The gas utility, or 911 | The propane supplier, or 911 |
| Smell | Added odorant, sulfur-like | Added odorant, sulfur-like |
| Reaction | Leave first, call from outside | Leave first, call from outside |
Five situations, and the right move in each
Real leaks rarely announce themselves tidily. These short scenarios show how the rule works in practice.
| Situation | What to do |
|---|---|
| You smell gas in the basement but the upstairs seems fine | Gas can collect low or high. Leave anyway, then call from outside. Do not go down to check the source. |
| The smell is strongest outside near the meter | Move away from the area, keep others back, and call the utility or 911. |
| A detector alarms in the middle of the night | Wake everyone, leave together, and call from outside. Do not silence the alarm and go back to bed. |
| You just moved the stove and now notice a faint odor | Treat it as a leak. Leave, call, and have a plumber examine the connector before the stove is used again. |
| A rental unit smells of gas | The same rule applies: leave, call the utility or 911, then tell the landlord or property manager. |
Myths that waste time during a gas scare
A few widely repeated beliefs lead people to hang around longer than they should.
- “It is probably nothing”Gas smells are never confirmed by guessing. A meter reading is the only way to know.
- “I will find it first”Searching for a hiss or sniffing along pipes keeps you inside. That is the opposite of what helps.
- “Open a few windows and wait”Ventilation may thin the gas, but it does not remove the source, and you still need the utility to check.
- “A pilot light went out, that is all”An extinguished pilot can mean gas is flowing. Leave it alone and call.
- “I will tell my landlord tomorrow”Report to the utility or 911 now. Notify the landlord after.
A household plan you can set up this week
A plan made on a calm day beats improvising at 2 a.m. These steps take little time.
Pick a meeting spot
Choose a place across the street or at the end of the drive where everyone gathers.
Post the numbers
Put the gas utility emergency line on the fridge and in your phone contacts. It is on your bill.
Walk the exits
Show everyone, including guests staying over, the quickest way out from each bedroom.
Plan for pets
Keep leashes and carriers by the door so leaving takes seconds.
Check the detectors
Press the test button, and replace batteries or units on the schedule printed on them.
Habits that make a leak less likely, or easier to catch
Nothing eliminates the risk of a leak entirely, but small habits help.
Add detectors
A natural gas detector near appliances, and a CO alarm outside bedrooms. Test them on the schedule the maker gives.
Know the smell
Make sure everyone in the home, including children, knows the sulfur odor and the rule to leave first.
Move appliances gently
Pulling a stove or dryer out can bend its connector. Ask a plumber to check after any move.
Call before you dig
Before any digging in the yard, have buried lines marked through the free locate service for your area.
Keep vents clear
Flues, vent pipes and intake openings blocked by snow, debris or storage can cause combustion trouble.
When to call a plumber about gas
Leave first if you smell gas. After the utility has dealt with the emergency, these are the reasons to call a plumber.
The utility has shut off the gas
A plumber can find the leak and repair the line or appliance connection.
You want an appliance connection checked
Especially after moving a stove or dryer, or if a connector looks worn.
A new appliance needs a gas line
Extending or modifying lines is plumbing work, done with the system tested afterward.
A repeat, faint smell
A weak odor that comes and goes still deserves attention. Call the utility first.
Gas services for after the emergency
Once everyone is safe and the utility has cleared the house, these services cover the repair side.
Gas leak repair
Finding and fixing the source of a leak after the utility clears the site.
Gas leak repair details →Gas line repair
Repairs and replacements for gas piping.
Gas line repair details →Emergency plumber
Help any hour for urgent plumbing problems.
Emergency plumber details →Water heater repair
Gas-fired heater problems checked once it is safe.
Water heater repair details →Gas leak questions people ask
What are the first signs of a gas leak in your house?
A rotten-egg smell is the most common sign. A hissing sound near a pipe or appliance and unexplained headaches or dizziness that improve outdoors are other signs. Leave if you notice any of them.
Should I open windows if I smell gas?
No. Do not stop to open windows or look for the cause. Leave right away and call from outside, since every minute indoors increases the exposure.
Who do I call about a gas leak?
Call 911 or your gas utility’s emergency number from outside the building. The utility’s number is usually on your bill or on the meter. Plumbers handle the repair after the emergency response.
Can I use my cell phone inside to call?
Leave first and call from outside. Using electronics inside the house is not worth the small chance of a spark.
Is a faint smell still a leak?
It can be. A small leak or a leak in a crawl space can produce a faint odor, and noses tire quickly. Treat any gas smell seriously and call the utility.
What if the smell goes away on its own?
Call anyway. Gas can drift, and the source may still be there. A utility crew can test with a meter and tell you for certain.
How much does gas leak repair cost?
Price depends on the source, the pipe or appliance involved and how hard the area is to reach. Ask about pricing when you call. The first step in every case is to get safe.
Can a gas leak happen with an electric stove?
Yes if the house has other gas equipment, such as a furnace, water heater or dryer. Gas smells can come from any of these, or from a line outside the house.
Do I need a plumber after the utility comes?
If the utility finds a leak inside the home, a plumber repairs it. The gas may stay off until then. Many plumbers are available same-day, and you can call anytime.
What if I smell gas outside but not inside?
Stay away from the area and call the utility or 911. Outdoor leaks near meters and buried lines are just as serious, and gas can travel underground into buildings.
Other safety and repair guides
Gas repair after the utility clears your home
If anyone smells gas right now, leave and call 911 or the utility first. For repairs afterward, call any hour.