Plugging a space heater into a power strip could have catastrophic results, firefighters warn.

With cold temperatures affecting most of the country, Umatilla County Fire District 1 in Oregon posted an alert in hopes of keeping people safe.

"These units are not designed to handle the high current flow needed for a space heater and can overheat or even catch fire due to the added energy flow," Umatilla County Fire District 1 wrote on Facebook.

An image accompanying the post shows a charred power strip from one of the department's own fire stations.

"Even the firefighters need a lesson," the post said. "The point comes down to proper use. Even the best equipment can fail if not used correctly. No one manufacturer is at fault, yet it’s all about the end user's ability to use the product safely."

Using an extension cord with a space heater is a no-no, as well, according to TV station WCVB.

To be safe, WCVB says space heaters should be plugged directly into wall outlets. That what most manufacturers recommend.