Everyone likes scoring a good deal when shopping online but state fire marshals say buying a smoke alarm online is a bargain you shouldn't risk.

The Tennessee State Fire Marshal's Office is issuing an advisory to consumers about purchasing certain smoke alarms online.

Chattanooga Fire Marshal Beau Matlock said some of the smoke detectors available online are not tested to nationally-recognized standards.

READ MORE | TN State Fire Marshal warning

 “Online retailers are selling smoke detectors that have not been tested through an independent party and that exposes them to an undue risk if the alarms aren't working correctly,” Matlock said.

The National Association of State Fire Marshal's Office has flagged: X-Sense, Arikon and Bovon smoke alarm brands sold on sites like Amazon and eBay.

The organization says these companies lack third party testing recommended.

“They have to meet UL standard and in order to meet that standard it has to have testing from a third party and those two companies provide the service,” Matlock added.

Fire marshals around the country are advising residents and urging the Consumer Product Safety Commission to Investigate and have online retailers remove the possibly faulty alarms off their sites.

“You rely on these alarms to give you early indication to get up and get out and without that, without the device working as it was intended or designed to it will delay that response," Matlock said.

Matlock said most alarms are relatively inexpensive, on average about $20 dollars in store. He suspects the people purchasing them online are likely buying them in bulk for multiple properties