Oil-based paints and wood finishing products such as linseed oil or tung oil contain “drying oils“, an oil that hardens after exposure to oxygen in the air. This hardening process, “oxidation”, is a chemical reaction that generates heat. If the heat is not allowed to dissipate, spontaneous combustion is possible within a few hours. Waste cans containing oily rags, cloth, or paper have been known to catch fire without warning.
These products must be used with the oversight of Fabrication Lab staff, stored in the flammables cabinet in L34, and any rags, towels, or other saturated media should disposed of with the assistance of Fabrication Lab staff.
Please see also these tips from the National Fire Protection Association (NFPA) about preventing fire caused by the spontaneous combustion of oil-based products.