An investigation of the July 4 fire that destroyed the Otis Cafe, outside of Lincoln City, has determined the cause to be spontaneous combustion of kitchen waste. Multiple agencies collaborated for the fire investigation at the Otis Cafe, at 1259 Salmon River Highway (Hwy. 18). The fire investigation team was comprised of agencies in Lincoln County and the area Deputy State Fire Marshal of the Office of State Fire Marshal, who are trained in fire investigations. The Lincoln County fire investigation team included North Lincoln Fire, Newport Fire, the Newport Police Department, and the Lincoln County Sheriff’s Office. The Newberg Police Department assisted with video retrieval, which supported the investigation.Fire-damage evidence indicated the fire’s origin was in the cafe’s kitchen, near the cooking range. Investigators concluded the cause was spontaneous combustion of combustible items such as paper towels absorbed with oil and grease waste, improperly discarded underneath the gas range in a plastic bucket. Spontaneous ignition can occur with the combustion of a material by an internal chemical or biological reaction that may produce sufficient heat to ignite the material. This may be a slow process. There are four elements to a fire, which include heat, fuel, oxygen, and chemical reaction. Spontaneous combustion is the result of chemical reaction. When paper towels — or similar combustible fibrous material — and grease or oil are improperly disposed, the oil can oxidize creating heat within the material. When this heat cannot dissipate, open combustion can begin, which can threaten property and may lead to injuries or loss of life. This incident serves as a reminder to discard used, oil-laden towels and fabrics in a closed top, non-combustible container made for their disposal — outside and away from combustible structures. Professional cleaning companies can be used for properly removing cooking oil from towels. Heat from dryers have also been known to cause fires with towels and rags due to oil residues on towels heating up. For safe disposal, soak used towels and linens in water within a non-combustible container, such as a metal can with a tight fitting lid, to prevent oil oxidation and the fibers from heating and igniting. Towels and oil saturated material may also be flattened out to dry in safe and noncombustible locations, and then properly disposed. For commercial grease disposal, businesses should contact their local disposal companies for policies of waste removal, which is typically a metal container maintained outside and away from the building.