Kerosene heaters work by using a wick that has absorbed kerosene, and after being ignited, the flames from the wick enter the burner unit to produce heat. The burner unit is designed to provide oxygen and distribute the flames from the wick, which is controlled by altering the wick's height.
After the kerosene inside the fuel tank has been absorbed by the wick, the kerosene undergoes a primary combustion process with the help of a specialized ignition plug. This process causes the kerosene to vaporize and burn in order to create flames and generate heat. The burner unit has a mechanical control that can increase or decrease the amount of air that enters the base of the heater. The height of the flame is also controlled by increasing or decreasing the amount of wick exposed inside the burner.
Kerosene heaters work in the same way as kerosene lanterns or lamps. The wick is typically circular and created using cotton or fiberglass materials. The wick is placed inside the burner unit, and this unit can heat nearby items using radiation or heat the air using convection. The heater can be extinguished by completely lowering the wick into an small area under the burner, which puts out the flame.
Also known as paraffin heaters, kerosene heaters are portable, unvented space heaters generally used as supplemental heat in homes without central heating in every room or as a source of heat during power outages, when conventional heat sources are unavailable.
While safer in 2015 than they were even a decade previously, kerosene heaters still pose a risk of accidental fire owing to operator error, such as not providing sufficient ventilation or using the wrong type of fuel. Other potential fire hazards caused by operator error include improper storage of combustible fuels and general carelessness while adding fuel. Kerosene heaters, along with electric space heaters and wood stoves, pose a far greater risk of fatal fire than central heating. Some health officials warn against using kerosene heaters, often citing the potential health risks involved in breathing the fumes.
Modern safety enhancements to kerosene heaters include automatic extinguishing devices, protective metal grills, carrying handles and lift-out fuel canisters. Other improvements include battery-powered ignitions, fuel gauges and leveling indicators.