<P> When filling a kerosene heater, there is an opportunity for the fuel to vaporize and create an odour in the air . This is why it is important to fill the heater in a garage or outdoors . When a kerosene heater is first ignited, it takes a few seconds to a few minutes for the fuel to mix with the air in the perfect ratio for complete combustion . During that time, the fuel to air mixture is quite rich . This results in a small amount of unburned kerosene, thus creating an odour . A common strategy is to light the heater outdoors, on the patio for example, until the fumes dissipate, and then bring it indoors . Once the heater is burning normally, no additional odour is created . An improperly adjusted wick also causes smoke and odour . This is corrected by adjusting the wick - height . A wick with carbon build - up will also cause odour and should be replaced . Odour may also be apparent when the heater is extinguished . The wick holder remains quite warm, and as the wick continues to draw kerosene, it causes vaporization of the fuel which is detected as odour . </P> <P> The wicks require routine maintenance . With fiberglass wicks, the kerosene heater is placed outdoors and allowed to operate until it runs out of fuel . Tar and other leftover deposits on the wick are burned off . This should be done at least once a week if operated 24hr a day . With cotton wicks, the heater must never be run dry to clean the wick . Cleaning is instead accomplished with a paper towel, wiping down the top of the wick to remove any residue . The wick will eventually deteriorate to the point where it will need to be replaced . </P> <P> Because kerosene heaters are usually unvented, all combustion products are released into the indoor air . Among these are low levels of nitrogen dioxide and carbon monoxide . An improperly adjusted, fueled, or poorly maintained kerosene heater will release more pollutants, particularly through incomplete combustion . Use of a kerosene heater in an improperly ventilated home poses an extreme risk to life . If oxygen is burnt faster than the extraneous atmosphere can leak into the room to replenish the burnt oxygen, the proportion of carbon monoxide rapidly increases . Since the monoxide cannot escape, any person in the room will fatally succumb to the poisonous gas . Human senses only detect an excess of carbon dioxide, and death occurs before any occupants of the room sense there is something amiss . Most manufacturers recommend that a window or door be left cracked open . Kerosene heaters should not be left unattended, especially when sleeping . A kerosene heater, as any heater that uses organic fuel, can produce dangerously high amounts of soot and carbon monoxide when running out of oxygen . Failure to follow safety precautions could result in asphyxiation or carbon monoxide poisoning . </P> <P> Hot surfaces on the heater pose a fire and burn risk . The open flame poses an explosion risk in environments where flammable vapors may be present, such as in a garage . Use of improper or contaminated fuel could cause poor performance, a fire or an explosion . There are the usual risks involved with the storage of kerosene and when refilling the heater . </P>

Is it safe to sleep with kerosene heater