According to the Centers for Disease Control and Prevention, carbon monoxide poisoning is the No. 1 cause of death by poison in the United States.

It was such poison that killed a teenager and effected at least 10 others in a leak Saturday, April 1, at a Niles, Mich., hotel pool. It was determined levels were 16-times higher than what's considered safe, and a faulty pool heater ventilation system is blamed.

"Gas logs, furnaces, water heaters, ovens are all big sources of carbon monoxide," Schaafsma Heating and Cooling president Kevin Walsh said.

Essentially, anything that burns produces some level of carbon monoxide, which is why detectors are a crucial investment.

"You can buy them for anywhere from $30 for a regular ones," Walsh said. "If you want a low level one, that might cost you $130, there's all kinds of them out there, there's no reason not to have them in your home."

Just because you have a working smoke detector doesn't mean it detects carbon monoxide.

"You do have some that our combination, and can do both, but you got to make sure what you're buying," Walsh said. "Most smoke alarms do not do carbon monoxide."

While you can sometimes smell a fire or see smoke, carbon monoxide is invisible.

"Carbon monoxide is colorless, odorless, tasteless; you have no idea it's even in there or that you're breathing it," Walsh said.

"Because we can't smell it or taste it having detection devices is extremely helpful," Healthy Homes Coalition of West Michigan Executive Director Paul Haan said. "Having an alarm go off because there's too much carbon monoxide in the air can be a lifesaver."

In the most recent case, the kids probably didn't realize that what they were feeling was as a result of the carbon monoxide.

"You don't realize it, because it's just creeping up on you and it's dulling your senses, so you don't realize what's happening to you until it's too late," Walsh said.

"You might get a headache or upset stomach, I can only imagine these children playing in the pool, they were excited -- they weren't really paying attention to those symptoms," Haan said.

Walsh said you'll want to make sure you're getting your device inspected annually and buy a new one every five years.

The Healthy Homes Coalition of West Michigan offers a free carbon monoxide detector to anyone living in Kentwood, Wyoming or Grand Rapids with a child 14 years old or younger.

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