The invention of Kerosene and Paraffin (used for making candles), was a major step forward in technology, impacting the everyday lives of the entire population. Kerosene or K-1 is another by-product of crude oil, however, this fuel is more refined than #2 oil, and has a lower gel factor.

This gel factor is very crucial to homes that have outside above ground storage tanks. Kerosene will not thicken when the temperature falls below freezing and #2 fuel oil will gel. Kerosene is most frequently used by mobile homes and must be used for heating units manufactured by Monitor and Toyotomi.