The Utility Locator Service at 811 makes sure underground pipelines and other utilities are clearly marked ahead of time so people can dig a safe distance away from them. This helps prevent serious accidents, because if people dig into these pipelines, they can be damaged and natural gas can leak out. Even a small leak can cause a fire hazard.
The five signs of an outdoor gas pipeline leak are:
A sulfur-like or rotten-egg smell
Dirt spraying or blowing into the air
A hissing or roaring sound
Continual bubbling in water
Grass or plants dead or dying for no apparent reason.
If you suspect an outdoor gas pipeline leak:
Leave the area immediately and move to a safe location.
Ask a trusted adult to call 911 and the local natural gas utility.
Do not go back to the area near the leak until safety officials say it is safe.
Do not use fire or electricity—a spark from a match, phone, or electrical device (even a doorbell or radio) could ignite the gas.
c) If you see a colored flag, you should leave it alone. These flags show people where buried utilities are located so they can dig safely away from them.