Natural gas, often simply called "gas," is used in homes to run many appliances. Gas is colorless and, in its natural state, odorless. The special "gas smell" is added to natural gas to let you know of a leak. It smells like rotten eggs or rotten cabbage. Whether the leak is large or small, it's important for your safety and the health of your family to take action immediately. Natural gas is a fire hazard, it's explosive, and inhaling it can damage health.

You may want to buy a natural gas detector for your home, particularly if your sense of smell is not good. A carbon monoxide detector will not detect a natural gas leak. The two are different gases.

While this article is about the dangers of leaking gas, natural gas has a good safety record, and natural gas emergencies are unusual events.

When digging outside, if a gas line is damaged, follow any applicable steps from the next section of this article, including calling the gas company right away. Indications of damage to a gas pipeline include a gas smell, a hissing sound, dirt blowing, or bubbles rising in sitting water.

If you suspect a gas leak in your home, take action immediately:

1. If there are cigarettes burning or any open flames, including pilot lights, put them out immediately and properly.
2. Avoid any possible sources of electrical sparks. Do not turn on or off any electrical appliances or lights, do not use the phone, and do not plug in or unplug electrical appliances.
3. If it’s a very small leak, open all the doors and windows. If it’s larger, don’t take the time for this step.
4. Get everyone out of the house.
5. If you can, turn off the gas at the meter for your home. It is outside the home. Usually, the valve is on a vertical pipe to the left of the meter. The valve handle should be a straight blade. Use a crescent wrench or pipe wrench to give the handle a quarter turn so that it is perpendicular to the pipe – so that it looks like it’s sitting across the pipe as if it’s “blocking” it. (It is a good idea to hang such a wrench near the meter for emergencies.)
6. From a safe distance, right away call your gas company and 911.
7. Do not turn your gas back on and do not re-enter the house. Your gas company will take the next steps.

If your gas company tells you to fix a gas pipe leak, you will need a licensed professional plumber. The plumber will fix your gas pipe so that your home is safe and sound and it's safe for the gas company to turn your gas back on.