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What does a gas leak smell like? How to identify a gas leak



Natural gas is considered a relatively clean and efficient way to power furnaces, fireplaces, clothes dryers, stoves and other products commonly found in homes. If a gas leak occurs through mishandling or misfortune, you could be at risk of a fire or gas poisoning. 

If you use natural gas in your home, it’s important to ask yourself some questions: What does a gas leak smell like? How can I respond safely? 

This article helps you identify and deal with potential gas leak problems.


6 signs of a gas leak in your home

According to the American Gas Association (AGA), around 177 million Americans use natural gas for home heating, powering their water heaters, cooking and more. Natural gas has become an indispensable part of today’s lifestyle. Because this heat source is essential to most of us, it’s important to understand the signs of potential gas leaks in your home.

You notice a rotten-egg smell

Because a natural gas leak can have deadly results, it’s purposely given the distinct smell of rotten eggs to bring the urgent problem to your attention. In its original form, natural gas is colorless and odorless. To help detect the smell of gas, a harmless chemical called mercaptan is added to give leaked gas a distinctive odor. Most people describe the scent like rotten eggs or a hydrogen sulfide odor.

Utility companies aren’t the only ones to use the mercaptan additive. Other industries also use it for jet fuel, pharmaceuticals and livestock feed additives, among other things.

Other gases have smells. For example, liquid petroleum gas (LPG), a mixture of propane and butane, is also odorless. Manufacturers add the agent ethyl mercaptan to the LPG gas mixture for safety’s sake, creating a recognizable scent familiar to anyone who’s been near a gas cylinder barbecue. In addition, manufacturers make the smell of fluorine gas similar to a chlorinated pool or bleach.

You hear a hissing sound

Natural gas leaking from pipes or appliances has a roaring or hissing sound depending on the size of the leak. 

Check your pipes and appliances on a regular basis to see if you can hear hisses.

A hissing sound near your air conditioner unit could be a sign of a leaking refrigerant line, a leaking valve or a bad compressor. If you observe any of these signs, turn off the unit and call for professional help.

Your plants are dying

Dead or dying houseplants could be a sign of a gas leak, especially if your plants are well cared for otherwise. Natural gas can stop a plant’s roots from absorbing necessary oxygen, leading to wilting. This lack of absorption can also cause smaller-than-normal leaves on plants.

In addition, look outside for yellow grass and dead vegetation — you might have a leak in the gas pipes under your lawn.

Your health takes a turn

Headaches, dizziness, fatigue, nausea and irregular breathing could be signs of exposure to low levels of natural gas. High-level exposure symptoms include severe headaches, extreme fatigue, issues with memory and concentration, nausea, passing out and suffocation. You should evacuate the premises and see a doctor if you experience any of these symptoms.

You have continuous bubbling in standing water

Natural gas leaks can happen in underground pipes outside your home. Besides dead grass and plants, a natural gas leak might show itself as continuous bubbling in standing water, such as puddles or mud. It’s a good idea to contact a professional if you notice a series of tiny bubbles popping throughout the still water on your property. 

A ruptured gas line can also manifest as an unusual cloud of mist or fog around your home or land.

You’re paying higher-than-usual gas bills

While there can be seasonal or environmental differences in your home’s gas prices, a sudden, unexpected increase could mean a gas leak. If you notice an out-of-season increase on your regular gas bill, look for additional signs of a gas leak (such as hissing, dead plants or rotten-egg smells). If you notice anything out of the ordinary, it’s time to call a professional for assistance.


What to do if you smell natural gas in your home

If you smell or otherwise detect a gas leak, an immediate response is essential to maintain public safety. To help prevent serious illness, don’t ignore gas odors or other signs of a leak.

If there are gas odors around an appliance, such as a furnace or stove, it might be that a pilot light has gone out or a burner valve is open slightly. You can usually identify and fix these problems yourself with proper guidance.

Otherwise, immediately call your gas company for help if you smell gas. If the smell is strong, leave your home first and then phone from outside or a neighbor’s home. 

There are a number of things you can do to help keep you and your loved ones safe while waiting for assistance, including:

  • Don’t use any electrical equipment or lights that might create a spark near the area of the odor.

  • Put out all open flames.

  • Don’t smoke or strike any matches.

  • Don’t light any candles.

  • Keep everyone away from the area of the odor.

  • Don’t use the doorbell.

  • Don’t adjust thermostats or appliance controls.

  • Don’t use elevators.

  • Don’t use a telephone.

  • Don’t flip light switches on or off.

If you suspect a gas leak outside, you should get to a safe place away from the premises and phone your gas company’s customer service hotline for help. Don’t try to locate the source of the leak yourself or operate powered equipment (such as a vehicle) near leaking gas. 

Most gas utilities offer 24-hour emergency service. To prepare for a call about a leak, include your gas supplier’s phone number and any other emergency numbers, including the local fire department.

Who pays for a gas leak?

Sometimes, gas companies will claim responsibility for leaks on their side of the meter (the pipes running from your house underground to the main). Homeowners will typically be responsible for leaks from the meter to the systems and appliances throughout the house. 

However, this isn’t always the case. Depending on several factors, homeowners could find themselves responsible for any costs related to gas leak repairs or damages. Understanding the potential costs and catching leaks quickly by paying attention to these signs can help you prepare for an event such as a gas leak.


How can I prevent a gas leak?

Taking some basic precautions might save you from the high cost of a gas leak.

When working to prevent gas leaks in your home, things to pay attention to include: 

  • Regularly inspect gas appliances and devices that operate with natural gas. These include furnaces, electric clothes dryers, water heaters, stoves and electric generators. 
  • Make sure any pilot lights are on. Flames should be small and blue with a yellow tip.
  • Routinely call in gas and plumbing professionals. Professionals can properly assess the state of your gas lines and the devices that use them. 
  • Install natural gas detectors in your home to work beside your smoke and carbon monoxide detectors. While detectors for carbon monoxide poisoning won’t alert you to gas leaks directly, they can detect when appliances improperly burn natural gas, kerosene or other fossil fuels. 
  • Familiarize yourself with your natural gas shut-off valve. This valve will help you cut off any further supply in case of a leak.


Protect your home from costly appliance repairs with Cinch

One way to help protect yourself from costs when your home’s major appliances and built-in systems malfunction is with a home protection plan from Cinch Home Services. 

If you operate a gas range stove in your home, it’s important to understand the risks of a gas leak and the potential cost of repairs. Thankfully, the Cinch Complete Home plan helps cover major appliances and built-in systems like your HVAC, stove and water heater. In addition, the Appliances plan can also help cover your gas range stove from damage caused by normal wear and tear. 

Cinch plans are designed to provide peace of mind by helping you access maximum coverage, with a 180-day workmanship guarantee, protection for pre-existing conditions and readily available service by vetted professionals. Reach out today for your instant quote!


To prevent natural gas leaks that can cause fire or gas poisoning, you need to effectively detect and deal with the threat.