The most common sign of a natural gas leak is a distinct sulfur or rotten-egg smell, which utility companies intentionally add to naturally odorless gas so leaks can be detected. Other warning signs include a hissing sound near a gas line or appliance, dead or discolored vegetation in an otherwise healthy area of the yard, and physical symptoms like dizziness, nausea, or headaches with no other clear cause. If you suspect a gas leak, leave the property immediately and call your gas utility’s emergency line before contacting a plumber.
Common Signs of a Gas Leak
- Rotten egg or sulfur smell the most recognizable and immediate warning sign
- Hissing or whistling sound near a gas appliance, meter, or line
- Dead or dying vegetation in a localized area, particularly along an underground gas line’s path
- Bubbles in standing water or wet ground, if a leak is near an outdoor line
- Physical symptoms dizziness, nausea, headaches, or fatigue that improve after leaving the house
- A higher-than-normal gas bill with no change in usage, which can indicate a slow leak
- Visible damage to a gas line, such as a dent, corrosion, or a line that’s been disturbed by digging or construction
What to Do If You Suspect a Gas Leak
- Leave the house or building immediately. Don’t stop to investigate the source.
- Do not use light switches, phones, or any electronics inside the home, a spark near leaking gas can be dangerous.
- Do not attempt to locate the leak yourself.
- Once safely outside, call your gas utility’s emergency line to report the suspected leak.
- After the utility has cleared the area, contact a licensed plumber to inspect and repair the source of the leak.
This order matters! Get out first, then call, rather than investigating or trying to shut off gas appliances inside the home.
What Causes Gas Line Leaks?
Gas line leaks can develop from several sources:
- Corrosion older metal gas lines are vulnerable to corrosion over time, especially in humid or wet soil conditions
- Physical damage lines disturbed by digging, landscaping, or construction without proper utility locating first
- Faulty connections loose or improperly sealed fittings at appliances or the meter
- Ground shifting similar to water lines, gas lines buried underground can be stressed by soil movement
- Aging appliances old or poorly maintained gas appliances can develop leaks at their connection points
Can a Small Gas Leak Be Dangerous?
Yes. Even a small, slow leak can be dangerous over time, both from a health standpoint (prolonged exposure to low levels of natural gas can cause headaches, dizziness, and fatigue) and a safety standpoint, since gas can accumulate in enclosed spaces and become a fire or explosion risk if it reaches an ignition source. Any suspected leak, regardless of how minor it seems, should be treated seriously.
How Is a Gas Line Leak Repaired?
Once a leak is confirmed and the area is safe, a licensed plumber typically:
- Uses specialized gas detection equipment to pinpoint the exact leak location
- Determines whether the affected section can be repaired or needs replacement
- Repairs or replaces the damaged section of pipe or fitting
- Pressure-tests the line to confirm the leak is fully resolved before restoring gas service
Gas line work should only be performed by a licensed plumber, since improper repairs pose serious safety risks.
Frequently Asked Questions
What does a gas leak smell like?
Natural gas itself is odorless, but utility companies add a chemical called mercaptan, which produces a distinct rotten egg or sulfur smell specifically so leaks can be detected by smell.
What should I do first if I smell gas in my house?
Leave the house immediately without using light switches, phones, or other electronics, then call your gas utility’s emergency line from a safe location outside.
Can a gas leak make you sick?
Yes. Symptoms of gas exposure can include headaches, dizziness, nausea, and fatigue. These symptoms typically improve once away from the source, which can be a helpful clue in identifying a slow or hidden leak.
Is it safe to try to find a gas leak myself?
No. Locating a gas leak should be left to your gas utility and a licensed plumber using proper detection equipment, attempting to investigate yourself, especially using an open flame, is dangerous.
Does Wilcox Plumbing repair gas lines?
Yes. Wilcox Plumbing provides gas line repair and installation for homes and businesses throughout Justin, TX and the surrounding area. Call 940-999-6103 for service.
Wilcox Plumbing is a family-owned, licensed plumbing company (Master Plumbing License #45464, Rodney D. Wilcox) with over 35 years of experience serving Justin, TX and the surrounding North Texas area. This article is for informational purposes; always contact your gas utility immediately if you suspect an active leak.