Cheyenne Fire Rescue is warning consumers about dangerous so-called safety devices being sold online.

Prevention Chief Byron Mathews says several companies are selling smoke and carbon monoxide alarms that haven't been tested and certified, creating a potentially deadly scenario for the consumer.

The sellers include Alert Plus, Alert Pro, Aricon, BQQZHZ, Elvicto, Lecoolife, MODOAO, Sunnec and Vitowell.

"Our concern is that these untested devices may not alert the occupants in a home of a fire, or sound an alarm or even operate properly," said Mathews.

Mathews encourages consumers to use products that are listed by a qualified testing laboratory such as Underwriters Laboratories and Edison Testing Laboratories.

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