Natural gas plays an essential role in many homes, fueling heating systems, cooktops and ovens, fireplaces, grills, clothes dryers, water heaters, and more. But if a leak occurs, gas can also pose health and safety hazards. So what are the signs of trouble?

The first and foremost hint is a sulfur odor, which resembles the smell of “rotten eggs.” The foul smell is actually from mercaptan—a chemical added to natural gas as a safety precaution since natural gas is odorless.

If you have gas appliances and detect this odor, you may have a leak. Gas is heavier than air, so any leak may be most noticeable on the lower floors, where gas will “settle.”

In addition to the smell of sulfur, other potential signs of trouble include:

• A hissing sound
• Discolored flames (yellow) rather than blue
• Dead or dying houseplants
• Higher than normal gas usage
• Discolored grass or greenery around your foundation or above the gas line’s path onto your property (which may indicate an underground leak)
• A white cloud or white “dust” near a gas line
• Gas pipes that have signs of corrosion or a green discoloration
• Physical symptoms of gas exposure in people or pets

Symptoms of Gas Poisoning

Young children, pets, and older individuals are particularly susceptible to gas poisoning. Long-term exposure can damage the cardiovascular system and cause brain damage, miscarriage, and death. Symptoms of gas poisoning include:

• Headache
• Dizziness
• Nausea
• Throat or eye irritation
• Fatigue
• Difficulty breathing
• Loss of color in the face

Potential Gas Leak: What You Need To Know

If you suspect a gas leak, take these steps immediately:

• Open the windows and doors where the smell is most noticeable.
• Get outside.
• Contact your local utility company once you’re safely outdoors. They will be able to detect a leak and turn off the gas supply, if necessary.

While waiting for the utility company to arrive, do not use electrical appliances. They may cause a spark that triggers a fire or explosion. Also, do not start any cars in the vicinity.

Do not re-enter your home until the gas company determines it’s safe to do so. If a leak is found, call a licensed plumber for repairs, get any necessary permits, and coordinate a final inspection with local authorities.

Preventing Gas Leaks and Safety Precautions

If you have gas appliances, you may want to schedule an annual professional inspection to ensure that your furnace is vented correctly, that no connections to your units have come loose, and that your pipes are free from corrosion.

To help prevent a gas leak, you should always:

• Be careful when moving a gas appliance to avoid crimping, breaking, or damaging the gas line.
• Keep the areas around gas appliances clear of flammable items (paint, paper, cardboard, etc.). 
• Never hang anything from or on a gas pipe, and remind children to stay clear of them indoors and outdoors.
• Keep the exterior meter free of weeds and debris.

It’s also a good idea to add the local fire department’s number into your cell phone contacts, along with the number for all utility companies, your preferred plumber, and HVAC professional.

If you live in a multi-family unit, be sure you have the contact numbers for all your neighbors so you can notify them in case of an emergency or suspected emergency—and make sure they have yours.

Also, you should never use aluminum foil to cover the slots, holes, or vents in the bottom of your gas oven or completely cover your racks since doing so can block airflow through the stove and poses a risk of carbon monoxide poisoning. Foil may also cause a heat buildup that leads to a fire.

Note: If your home uses any gas appliances, installing a carbon monoxide alarm is a good idea. Although a CO2 monitor or alarm will NOT detect a gas leak, improper venting of CO2 could prove to be a health risk or a death sentence for you and your family. A monitor to alert you to the danger will only cost a few dollars, although premium devices can cost $150 or more.