How to Detect a Gas Leak: Tips for Homeowners and Renters

Natural gas is used in homes throughout the U.S., most commonly in stoves and water heaters. They’re a popular and energy-efficient chemical that can help reduce your carbon footprint and increase your home’s value. In fact, homes with gas hookups tend to sell for more than those without. 

While natural gas is generally safe when properly used and maintained, leaks can occur and pose serious health and safety risks. Other gasses can cause problems as well, including propane, radon, and refrigerants. Additionally, burning natural gas produces carbon monoxide (CO), which can be deadly in enclosed spaces.

Household gas leaks are also increasingly common. A 2018 study found that U.S. fire departments respond to an average of 125,000 gas leak calls annually – an increase of 25% compared to 2007. 

Because of the danger, everyone must be aware of gas leaks, regardless of their living situation. Whether you’re a homeowner living in Boston, MA, or a new renter in San Antonio, TX, read on to learn how to detect a gas leak in your home.

How to detect a gas leak

A gas leak is dangerous because of the fire, exposure, or explosion risk. And while carbon monoxide (CO) isn’t caused by a leak, it can build up silently when gas appliances aren’t vented or maintained properly. It’s essential to identify the signs of a gas leak to prevent potential harm to yourself, your family, and your property. Here’s a quick checklist for you.

1. Install a gas leak detector
2. Smell for rotten eggs
3. Listen for hissing sounds
4. Look for bubbles outside
5. Notice dead or dying plants
6. Track gas usage
7. Monitor physical symptoms

1. Install a gas leak detector

If you don’t have them already, install a gas leak detector near sleeping areas and in utility rooms throughout your home. These devices are designed to detect the presence of combustible gases, such as methane and propane, and alert you before the concentration reaches dangerous levels.

You can also purchase a portable gas leak detector that you can take on the go. These are fairly inexpensive and quite accurate. 

If you want to use a homemade method, you can mix a teaspoon of soap into a cup of water, pour it over a suspected gas leak, and see whether bubbles show up. However, this is a last resort that should not replace a gas leak detector. 

Importantly, gas leak detectors do not scan for carbon monoxide – you need a separate carbon monoxide detector for that. Installing both types of detectors enhances safety by alerting you to multiple hazards: Gas leak detectors warn of combustible gas accumulations, while CO detectors alert you to dangerous levels of carbon monoxide.

2. Smell for rotten eggs

Natural gas is odorless in its natural state. To help detect leaks, utility companies add a harmless chemical called mercaptan, which smells like rotten eggs or sulfur. If you detect this smell indoors, evacuate immediately and contact your gas company or 911. 

It’s important to note that carbon monoxide is odorless, tasteless, and colorless. 

3. Listen for hissing sounds

Large gas leaks in pipes and appliances may produce a hissing or whistling sound. Once per month, check your appliances for unusual noises. 

4. Look for bubbles outside your home

Gas generally enters your home through underground pipes, which attach to the local gas main under the road. If there’s a leak beneath the surface, you might see bubbling in puddles or soil that appears to move. These are signs that gas could be escaping from underground pipes and displacing air or water.

5. Notice dead or dying plants

Natural gas leaks can suffocate plant roots by displacing oxygen in the soil. This can lead to wilting, yellowing leaves, stunted growth, or unexplained plant death, especially near buried lines or gas meters. Regularly monitor outdoor vegetation near these areas.

6. Track gas usage 

Gas leaks can be extremely minor and can go undetected for months. In these cases, it’s important to keep an eye on your gas usage. Checking your monthly utility bill and comparing it to prior months or neighborhood averages can help determine if you have a leak.

7. Monitor physical symptoms

Exposure to leaking gas or its byproducts, especially carbon monoxide, can be extremely dangerous. While checking for physical symptoms should never replace a detector or regular maintenance, it’s important to be aware of signs of potential exposure. 

Symptoms of exposure include headaches, dizziness, fatigue, weakness, nausea, and irregular breathing. In severe cases, prolonged exposure to carbon monoxide can lead to memory loss, comas, and death. If you’re experiencing symptoms of gas exposure, call a professional or 911, and seek healthcare as soon as possible.

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Who to call for a gas leak

If you think you have a gas leak, turn off your electricity and call a professional plumber, emergency utility maintenance, or 911. Most municipal gas companies have a 24-hour emergency line. Don’t use a landline if you suspect you have a gas leak; they can cause a spark, which can be extremely dangerous. 

You should never try to pinpoint the exact location of a gas leak – leave that to trained professionals. Exposure to carbon monoxide and methane is dangerous and can lead to explosions, physical symptoms, and property damage.

What causes a gas leak?

Gas leaks can lead to fires, explosions, and health problems. Because of this, it’s important to understand how gas pipes and appliances begin leaking, so you can prevent leaks in your home. Here are the five most common causes.

1. Fitting and connection issues

Fittings are the pipes, valves, and meters used to transport natural gas from the local gas main to your home. Connections are the points connecting different fittings. Poorly installed fittings and connections are common, and even expertly installed fittings can develop leaks over time.

2. Corrosion or damage to gas pipes 

Gas pipes develop corrosion over time, which can cause leaks to develop. This is a common cause of leaks, particularly in older homes and infrastructure. In fact, corrosion was the leading cause of gas leaks in the U.S. from 2009-2018. 

3. Poor appliance maintenance and installation 

Gas can leak if your appliances aren’t installed correctly and if you don’t maintain them. Common issues include damaged or worn-out gas hoses, burners, and poorly fitted seals. 

4. Appliance malfunctions 

Even new appliances can malfunction with regular use. If the malfunction affects the normal flow or combustion of the natural gas, it can leak. 

5. Natural disasters or external damage 

Weather, construction work, and other physical damage can all cause gas leaks. For example, an earthquake may rupture gas mains, or excavation work can accidentally hit your home’s gas pipes. If your home was recently affected by a natural disaster, checking for gas leaks should be on the top of your list.

Refrigerant leaks

Pay attention to appliances that use refrigerants as well. Refrigerants commonly contain gasses like freon and isobutane, both of which are harmful. If your refrigerator, A/C unit, or another cooling appliance suddenly stops working, shut them off immediately and check for leaks. Many standard gas leak detectors also detect refrigerants, but ensure you get one that does. 

Additionally, never try to fix your appliances; many states prohibit nonprofessionals from working with refrigerants due to their dangerous properties. If you detect a refrigerant leak, call a professional immediately.

How to prevent gas leaks

Preventing leaks is the first line of defense for every home. While it may take extra time, it’s critical to maintaining a healthy home. Here are some ways to stop gas leaks before they start.

• Ensure your gas pipes were installed by a professional: Improper installation is a leading cause of gas leaks in the U.S. If you’re installing a new appliance or upgrading an old system, make sure you hire a qualified master plumber. 
• Maintain fittings and appliances: Gas pipes and appliances wear down over time. You can check appliances yourself, but it’s best to schedule yearly gas maintenance with a master plumber. 
• Upgrade appliances: Old appliances are more likely to break and leak. They’re also less efficient and pricier to maintain. Upgrading your stove, water heater, or dryer can help reduce the risk of gas leaks.
• Switch to electricity: The most effective and permanent way to prevent gas leaks is to phase gas out of your home. Consider switching to all electric appliances and installing solar panels to mitigate the higher electric bill.

Final thoughts on gas leak detection

Detecting gas leaks is critical to maintaining a safe and healthy home. Although natural gas is an efficient and growing energy source, it has its drawbacks, including dangerous leaks, environmental concerns, and indoor air quality issues. 

To detect and prevent gas leaks, make sure to install a gas leak detector, as well as a carbon monoxide detector for added safety. Ensure your pipes, fittings, and appliances are installed correctly, and hire a professional for yearly check-ups. If you detect a leak, turn off your electricity, leave your house, and call your local gas company or 911. If you want to eliminate the risk of leaking gas, consider switching to electric appliances and phasing gas out of your home. 

If you detect any signs of a gas leak in your house or think you have been exposed, contact your local utility provider or call 911 immediately.