Firefighters Extinguish Garage Fire Caused by Oily Rags in Fort Collins
Poudre Fire Authority crews extinguished a garage fire on October 25 that ignited from the spontaneous combustion of oily rags used for wood staining earlier that day, officials announced.
Firefighters responded to the 3100 block of Eagle Drive shortly after 5 p.m. after residents returned home to find smoke coming from their property and called 911.
Engine 4 crew members stretched a hose line and conducted a 360-degree assessment of the two-story split-level home. Firefighters discovered smoke emanating from the garage and found the fire was mostly extinguished by the time they made entry. Crews fully suppressed the remaining flames, confirmed the fire had not spread into the house, and ventilated smoke from the garage.
No injuries were reported. All PFA units cleared the scene by 6:05 p.m.
The PFA fire investigation determined the cause was unintentional, originating from oily rags used for staining and applying clear coat earlier on October 25.
Chemical Reaction Creates Fire Hazard
Spontaneous combustion occurs when materials soaked in drying oils undergo exothermic oxidation after exposure to air, generating heat without an external ignition source.
Linseed oil, tung oil and many oil-based wood stains contain unsaturated oils that release heat as they cure. When oily rags are piled together or stored in enclosed spaces, heat accumulates faster than it can dissipate, eventually reaching the material's autoignition temperature.
Cotton rags absorb more oil than synthetic materials and present higher combustion risk. Poor ventilation, ambient heat and layered storage all accelerate the oxidation process that leads to ignition.
The time from oil application to ignition can range from hours to more than a day, depending on oil quantity, confinement conditions and temperature.
Authority Responds to Multiple Oily Rag Fires Annually
PFA responds to multiple fires caused by improperly stored oily rags each year, according to the department's announcement. The authority served 206,000 residents across Fort Collins, Timnath, LaPorte, Bellvue and surrounding areas in 2023.
PFA recorded 287 fire incidents in 2023 out of 25,349 total calls, according to the authority's annual report. The report does not break down fires by specific ignition source.
Safe Storage Requires Outdoor Drying or Water Submersion
Fire officials recommend laying oily rags flat in a single layer outdoors, away from structures and combustible materials, to dry completely in a cool, well-ventilated area such as shade.
Once fully dried, rags should be submerged in water mixed with detergent before disposal according to hazardous waste guidelines.
The Colorado Fire Code, which incorporates International Fire Code provisions, requires combustible waste materials including oily rags to be stored in metal containers with tight-fitting lids and disposed of regularly to prevent fire risk.
Residents can dispose of oily rags, oil-based paints and stains at the Larimer County Hazardous Waste Facility in Fort Collins. Both Larimer and Weld counties periodically hold household hazardous waste collection events.
Colorado homeowners who fail to observe safe storage practices and cause fires that spread to neighboring properties may be held civilly liable for negligence under state law.
PFA was established in 1981 through an intergovernmental agreement between Fort Collins and Poudre Valley Fire Protection District and operates 13 fire stations throughout northern Larimer and Weld counties.