Always use Colsen’s Fire Pit Fuel or specialized fuels for fireplaces with flame arrestor. Flame arrestors are highly effective in preventing flame jetting. Never use rubbing alcohol without flame arrestor, gasoline, kerosene, oils or other flammable substances with your Colsen Fire Pit. Do not attempt to refill the fire pit until the flame has had time to dissipate, while there is flame, or while the product is still hot or warm. Fire or explosion can occur.