Recognize a Natural Gas Leak
Be aware of signs you may see, hear or smell when there is a leak.
If you see a damaged connection to a natural gas appliance, dirt/water blowing into the air, a dry patch of grass, fire or an explosion near a pipeline.
If you hear unusual sounds like hissing or whistling.
If you smell the distinctive odor
of natural gas.
Don’t Rely on Just Your Nose
Although a distinctive odor is added to make natural gas easy to recognize, you may not be able to smell leaking gas if:
- You have a diminished sense of smell
- You’re experiencing odor fatigue (normal, temporary inability to distinguish an odor after prolonged exposure to it)
- You have a physical condition such as a common cold, sinus condition or allergies
- You use tobacco, alcohol, drugs and certain medications
- The odor is masked or hidden by other odors that are present
- Pipe and soil conditions have caused odor fade (see below)
Sometimes physical and/or chemical processes can cause a loss of odorant in natural gas, making it undetectable by smell. Odor fade can be caused by adsorption, absorption, oxidation or any combination thereof.
Odor fade is more likely to occur in the following situations:
- In new, steel pipe that has been recently manufactured or hasn’t been used for odorized natural gas before
- In natural gas piping systems using higher gas pressure, and when natural gas flow is limited or intermittent
- In the presence of rust, mill scale, moisture, air, cutting oil, pipe thread compound, liquids, condensates and other substances
Because of the possibility of odor fade, it's important to not rely only on your sense of smell to be alerted to a natural gas leak.
For a printable copy about odor fade and safe purging practices, see our Safety Bulletin.
If you have additional questions or concerns regarding pipe conditioning or odor fade, call us at 1-800-427-2200 or contact a licensed, qualified professional.
COVID-19 may cause a temporary loss of smell that could make it more difficult to detect the odorant that is added to natural gas to help make leaks easier to detect.