What Does a Gas Leak Smell Like?
Compare prices for local installers in your area
Join the 6,755 people who have received a free, no-obligation quote in the last 30 days
Written by
Natural gas provides heat to many homes across the country, powering gas appliances and systems such as the stove and water heater. While it is safe when contained within those appliances, a natural gas leak is highly dangerous and can cause a fire or explosion. Since natural gas is odorless and tasteless, a harmless substance called mercaptan is added to make the gas smell like sulfur or rotten eggs. In addition to the smell, there are other signs of a natural gas leak. We’ll identify those signs and tell you what to do if you spot them.
Use our expert research to learn more about your project
Enter your ZIP code and tell us about your home
Match with local experts who can meet your needs
A water softener system can cost $500–$6,000, depending on the type of system.
GET QUOTEIdentifying a Natural Gas Leak
Although natural gas isn’t toxic, a leak increases the risk of fire or combustion, making it important to identify the gas and find the source so that you can take the appropriate safety measures.
Rotten Egg Smell
Mercaptan or thiol is an additive in natural gas that produces an odor similar to rotten eggs. The specific scent may differ slightly by region, since it’s added by the utility company, so you can visit the company’s website for more information. If you smell this odor in the home, you could have a natural gas leak.
Continuous Bubbling in Standing Water
If standing water outside your home is bubbling, there could be a leak in your outdoor gas line. This is the effect of water dissolving the leaking natural gas, resulting in visible bubbles.
Roaring or Hissing Sound
Natural gas can softly hiss or roar as it escapes from a leaking pipe. Usually, the source of the leak is the natural gas connection at the back of an appliance, in which case you’ll most likely be able to smell the gas as well.
Dead Plants
If there’s a leak in the outside gas line leading to your home, dead or dying plants could signal an issue. When natural gas leaks into your lawn, it displaces the oxygen necessary for the plant’s roots to survive. If you notice dead plants in your yard despite proper gardening care, you could have a natural gas leak. The same could be true for your houseplants if you have a slow indoor leak.
Unnatural Dirt and Air Movement
The pressure released by a leak in your natural gas line can cause an unusual amount of air to blow across your yard. If there isn’t a noticeable natural breeze and you see dirt blowing out of your yard or air blowing across plants, you could have a natural gas leak. Sometimes an outdoor gas line rupture can even cause a white mist or fog.
Health Effects
Prolonged exposure to a natural gas leak can cause health problems. Additionally, recent studies have shown that residential natural gas in some regions contains air pollutants that cause long-term health problems. More research is currently being conducted to determine the size and nature of this risk.
In the short term, as natural gas continuously leaks into your home, it can affect your sense of smell and displace oxygen, causing breathing difficulties, headaches, and nausea. If you’re experiencing these symptoms and aren’t suffering from a separate illness or underlying condition, there’s a possibility you have a gas leak.
Get a Quote: Get a quote on your plumbing project today
What to Do If You Smell Natural Gas
Read More: Staying Safe with Natural Gas
How to Prevent Natural Gas Leaks
Although you can’t always stop a natural gas leak, there are some precautions you can take to minimize your risk.
- Regularly service your systems and appliances, checking them for wear and tear that can lead to a gas leak.
- Have your appliances and pipelines professionally inspected at least once a year to confirm there are no leaks.
- Learn where the main shut-off valve for your home’s natural gas supply is located. It’s usually outdoors.
- Make sure your family members know what to do if they smell gas.
- If necessary, contact a professional to have your gas fittings and shut-off valves replaced. This will prevent the old infrastructure from corroding and causing a leak.
Get a Quote: Get a quote on your plumbing project today
FAQ About Gas Leaks
What does a gas leak smell like in your house?
A substance known as mercaptan is added to your natural gas to give it a pungent rotten egg smell. If you notice this odor in your home, it’s possible you have a natural gas leak.
Who pays for a gas leak?
You as the homeowner are responsible for paying for the repair and damage caused by leaks in gas lines. Thankfully, some home warranty companies, such as American Home Shield, cover leaks and breaks in gas lines.
What should you do if you smell gas?
If you suspect a natural gas leak, open the doors and windows, turn off any open flams, exit your home, and contact 911 or your gas provider. For more severe leaks, leave the property immediately before contacting the appropriate authorities.
Find Plumbing Professionals in Your City
To share feedback or ask a question about this article, send a note to our Reviews Team at reviews@thisoldhousereviews.com.