Waterloo, IA – A Waterloo family is grateful after a close call over the weekend.

On Saturday. two carbon monoxide alarms went off in the home of Jari Engle, 1732 Mulberry St. At first, all four members of the family inside thought it was failing batteries.

But when the alarm wouldn’t quit, they called 911. Test meters for the odorless, colorless and deadly gas measure carbon monoxide in parts per million. Anything less than 10 ppm is considered normal indoor air.

Waterloo Fire Rescue meters averaged 74 ppm inside the Engle home, so firefighters told the family to get out.

Jari Engle said the culprit was a rusted exhaust pipe on the furnace. Saturday night, she had a splitting headache and figured it was just a migraine.

Then the two carbon monoxide detectors started shrieking.

“They saved our lives. If it wasn’t for them, the CO detectors, we’d probably be dead to be honest,” Engle said.

Engle’s mother, Donna Rasmussen, said firefighters told the family it was an extremely close call.

“They told us we could have both been dead by morning,” Rasmussen said.

Pat Treloar, Waterloo fire chief, said his department typically responds to about 25 carbon monoxide alarm calls a year.

Treloar said sometimes people pay so much attention to smoke detectors they forget carbon monoxide alarms play an important role in home safety too.

Treloar said homeowners are not required to install carbon monoxide detectors. But a rule change last January made both smoke and carbon monoxide alarms a requirement in rental housing.

In this case, it’s a rule that potentially saved four lives Saturday.

“It’s just as important, if not more important, than a smoke detector. I say that because we can, if awake, sense or smell smoke. We cannot sense or smell carbon monoxide,” Treloar said.

Engle said the family received Red Cross assistance for two nights in a local motel while the home was aired out and the furnace exhaust pipe fixed.

The family returned home Monday.