Buying a new space heater?
From the U.S. Consumer Product Safety Commission:
Select a space heater with a guard around the flame area or heating element. Place the heater on a level, hard and nonflammable surface, not on rugs or carpets or near bedding or drapes. Keep the heater at least three feet from bedding, drapes, furniture, or other flammable materials.
Choose a space heater that has been tested and certified by a nationally recognized testing laboratory. These heaters meet specific safety standards.
Keep doors open to the rest of the house if you are using an unvented fuel-burning space heater. This helps prevent pollutant build-up and promotes proper combustion. Follow the manufacturer's instructions to provide sufficient combustion air to prevent CO production.
Never leave a space heater on when you go to sleep. Never place a space heater close to any sleeping person.
Turn the space heater off if you leave the area. Keep children and pets away from space heaters.
Have a smoke detector with fresh batteries on each level of the house and a carbon monoxide detector outside your sleeping area.
Be aware that mobile homes require specially designed heating equipment. Only electric or vented fuel-fired heaters should be used.