SAN FRANCISCO (KGO) -- It may be time for you to install a new carbon monoxide detector in your home. A California law that went into effect in 2011 requires carbon monoxide detectors in residences. The detectors have a seven to 10-year life span, meaning many are due to be replaced. But just because you replace them doesn't mean things can't go wrong.
One San Francisco family's new detectors did not alarm despite high levels of carbon monoxide in at least one part of their condo. Now they want to know why.
Mom Madeline Wiginton says she thought she smelled natural gas in her condo last week. The building's boiler is older and had a build-up of soot. There was even a prior carbon monoxide scare in December. Still, Wiginton didn't fully trust her nose so she didn't call 911. Instead, she sent her husband out for carbon monoxide detectors.
"New ones that I could be really confident were working," said Wiginton.
She activated and tested them. Since it was late at night, she temporarily left one on here on her dining room table and another leaning up against the wall above a closet door in between her son's bedroom and the master bedroom.
That night, the carbon monoxide detectors in Wiginton's upstairs neighbor's condo alarmed, prompting him to call 911 and get everyone out of the building.
Wiginton's carbon monoxide detectors did not go off.
When the fire department arrived, they measured carbon monoxide levels of 33 parts per million in the condo where the detectors alarmed and 100 parts per million in Wiginton's bathroom where she didn't have a carbon monoxide detector.
The San Francisco Fire Department says because the measurement was 100 parts per million PGE expedited their response.
Higher concentrations of carbon monoxide are dangerous over shorter periods of time while lower levels of carbon monoxide become can become dangerous with exposure over longer periods of time.
"I don't even necessarily think there's something wrong with my detectors, but I don't know what else I can do to protect us because the unit above us which had lower carbon monoxide readings than we had their detectors did go off and they have the same brand of detectors," said Wiginton.
The detectors in both condos are manufactured by Kidde.
On Tuesday, Kidde's Spokesperson was at a press conference with the San Francisco Fire Department and Oakland Fire Department to educate consumers about carbon monoxide safety.
"What I would caution everyone is that placement of carbon monoxide alarms is critical," said Sharon Cooksey, Kidde Spokesperson.
Make sure to read manufacturer instructions and match the instructions to your particular environment.
Neither the Fire Department nor Kidde can say for certain why Wiginton's carbon monoxide detectors didn't alarm.
"CO mixes with the air and it just matters what concentration happens to enter into the environment," said Cooksey.
In addition to following manufacturer instructions, Kidde says never place a carbon monoxide detector near forced air, have at least one on every floor, outside sleeping areas and in every bedroom, test your alarms weekly and replace them every seven to 10 years.
Also make sure you know the difference between a carbon monoxide detector and a smoke detector. Wiginton didn't realize detectors already in her home were smoke detectors not carbon monoxide detectors.
"Maybe a story like this will somehow lead to people have a little more information," said Wiginton.
The boiler in the building has been turned off until it can be repaired. If you smell natural gas, you should leave your home and call 911.
Carbon monoxide is odorless. Having more carbon monoxide detectors in your home won't negatively impact readings but could save your life given that carbon monoxide readings could be higher in certain areas of a home versus other areas.