Natural gas leaks don’t always smell like sulfur

Recently, one of our team members got a reminder about how easily something we all take for granted – the natural gas that powers our stoves, water heaters, furnaces and dryers – can turn dangerous. She shared her story with Perspective:

'It happened to me'

"When you have a natural gas leak, you assume there would be that distinctive 'rotten egg smell' you always hear about. As my husband and I found out, though, that's not always the case.

"We smelled a funny odor, like onions or chives, while we were watching TV. We didn't think much of it until we headed to bed and noticed the smell was strong in the laundry room. There, we discovered a hissing gas line behind the dryer. It hadn't been used for at least 22 years.

"It turns out, a roll of garbage bags had toppled from a shelf and hit the on/off lever to the gas line (which we shut off immediately).

"In hindsight, because the onion smell didn't register with us as a sign of a gas leak, we did some things we shouldn't have. Instead of vacating and calling for help, we switched lights on and off and unplugged the dryer (things that could have created a spark). Had gas concentrations been high enough, we could have had an explosion.

"When we called the gas company, the technician said our story wasn't uncommon. Gas leaks, he said, do not always smell like sulfur, especially when it's leaking from a pipe that hasn't been used for a while.

"Luckily, we and the house escaped unscathed. And we know how fortunate we were." 

 – Peggy D.

 You can't just rely on your nose

Natural gas is highly flammable and, when it doesn't burn completely, emits toxic carbon monoxide. Nationwide, about 17 people a year lose their lives in gas explosions, and 500 die of carbon monoxide poisoning.

That's why gas companies add an odorant, mercaptan, to make the otherwise odorless gas detectable by smell. But as in Peggy's case, it's not always recognizable.

Here are other gas leak tipoffs to watch for:

• hissing sounds from pipes or appliances
• dirt or dust blowing around in a space where there's no wind
• bubbles appearing in an otherwise still body of water (gas leaking from a pipe that runs under a landscaping water feature)
• dead spots in the lawn that no amount of watering, replanting and fertilizer seem to fix (gas leaking from Ts in pipes that run under the turf)
• flu-like symptoms (headache, nausea, exhaustion) that strike suddenly and seem to affect everyone in the house.

If in doubt, get out
It's much better to call the gas company with a false alarm than risk your family's safety around a possible gas leak.

If the smell of gas is strong or you're feeling physical symptoms, get out immediately. Don't use the phone or anything electric (even switching off a light or using your garage door opener), which could create a spark. Find a safe place away from the property and call 9-1-1 and then your utility provider. Consider seeking medical help.

If the smell is faint or other signs of a leak are minor and you feel no symptoms, go through your home quickly and open windows and doors to keep gas from building up. Get out and call your utility company or 9-1-1 from a safe place.

Depending on your situation, your utility provider may coach you on turning off the gas yourself (you may need a special wrench) or dispatch an emergency technician. They have equipment that can detect the source of the leak, but they generally won't fix the problem (you'll need to hire a contractor for that). You'll want to make sure a qualified technician confirms all pilot lights and appliances are operating safely before you go back to using gas.

Ensure your peace of mind with a gas or propane detector

Make sure you're following recommended maintenance schedules for gas appliances like water heaters, furnaces, fireplaces, dryers and stoves. As part of their routine service, technicians will check gas lines and connections, perhaps spotting problems most of us might miss.

Also, consider buying a gas/propane detector. They look a lot like smoke and carbon monoxide detectors (larger, pricier models also include an automatic gas shutoff valve if a leak is detected). For natural gas, place them on the ceiling near the appliance. If you're using propane, which is heavier than air, put the detector closer to the floor. (Be sure to follow manufacturers' instructions.)

Detectors give you added peace of mind and you may be able to save on your insurance. PEMCO offers discounts when you use fire, gas, theft and water devices that have alarms, are self- or centrally monitored or have an automatic shutoff. Talk with your agent or contact PEMCO for details.