Kerosene, a versatile hydrocarbon fuel, powers jet engines and provides heat for homes and businesses. In the 1800s, it illuminated streets in what were known as hurricane lamps. Today, kerosene remains a critical fuel source, but its safe use depends on the sulfur content of the grade you choose.
1‑K is the purest form of kerosene, with a sulfur content capped at 0.04 % by weight. Its clear or slightly yellow appearance indicates minimal impurities. Because of the low sulfur, 1‑K can be burned in indoor appliances without a flue, provided the appliance is UL‑tested (Standard 647) and operated in a well‑ventilated space. Avoid red‑dyed 1‑K, which often contains extra additives that can increase fumes.
2‑K contains up to 0.30 % sulfur, significantly higher than 1‑K. This grade must be used only in appliances equipped with a flue, as the combustion by‑products can be harmful if inhaled. Heaters, in particular, should not use 2‑K because the higher sulfur disrupts fuel wicking, leading to frequent cleaning and a higher fire risk.
Before purchasing kerosene, always verify the grade on the label. When refueling a heater, ensure the unit has cooled for at least 15 minutes and perform the operation in a ventilated area away from ignition sources. Choosing UL‑certified appliances adds an extra layer of protection.
Kerosene boils between 302 °F and 572 °F, melts at –4 °F, and has a density of 0.8, meaning it floats on water. Its autoignition temperature is 428 °F, so proper storage and handling are essential.
