Space heaters can take the chill out of a cooler room and save on heating costs - but they can be also be very dangerous.
In fact, 40 percent of home heating fires are caused by space heaters.
Consumer Reports tested several models of space heaters, from personal-sized portable heaters to larger units.
"When we test heaters we check to see how fast they warm a room and we also check to see how well they spot heat an individual," said Peter Sawchuk with Consumer Reports.
A testing mannequin is equipped with sensors that measure how much warmth a space heater can provide through spot heating.
The smaller, personal-sized space heaters struggled in this important test.
Consumer Reports says for a little more money you can get one that's slightly larger but still very portable. It recommends the Comfort Zone CZ499R, which sells for $70.
Since space heaters can be a fire hazard Consumer Reports also looks at how safe each one is. Testers measure the surface temperature of each heater to see if it gets too hot to the touch.
"In most cases the heaters are pretty cool but if you do have pets or children stay away from heaters with metal surfaces and large areas that are easy to contact," Sawchuk said.
This test mimics what would happen if something flammable comes into contact with a space heater.
"Always keep your space heater at least three feet away from flammable objects," Sawchuk said. "And never use an extension cord."
Consumer Reports says look for a space heater with a tip-over switch that turns the heater off if it's knocked over, and an overheat sensor that shuts off the heater if it gets too hot.
The recommended Comfort Zone heater offers those safety features. If you'd like a larger space heater so does the Lifesmart ZCHT1001US for $100.
Consumer Reports rates space heaters for safety, effectiveness