With temperatures expected to dip into the 40s by early Thursday morning, the Alton Fire Department is reminding the public to be safe while staying warm.

Alton Fire Captain Emilio Ledesma told Channel 5 News people sometimes use gas stoves to heat their homes. Ledesma said first responders warn against doing that.

“Sometimes they forget they are left on and it builds up carbon monoxide in the residence,” Ledesma said. “You cannot smell it so the only factor is you will start feeling nauseous, headaches, and you will tend to pass out."

Space heaters are another option, but you do have to be careful when using them.

First responders say don’t place the space heaters near anything that can catch fire easily, don’t use extension cords, and keep them away from children and pets.

Also, remember to turn them off before you go to bed or leave your home.