For release agents made with these premium oils, increasing the spray pressure by 5 psi or so overcomes any spraying problems caused by thickening. With less sophisticated release agents and when temperatures fall below about 40 F many release agents thicken. Products made with diesel oil, kerosene, mineral spirits and some other common solvents fall into this confusing flash point range. Transportation regulations are an area of environmental and OSHA concern for release agents, curing compounds, sealers, waterproofing materials and coatings. Anything below a flash point of 100 F is always flammable by all agencies and there are three flammable DOT hazard classes.
Flash points are only one of several criteria for defining hazardous materials.
How Release Agents Work You need fatty acids to make a good chemically active type release agent. Fatty acids are derived from fat, from which they get their name. They are very, very weak organic acids much different from strong mineral acids like sulfuric acid or muriatic acid. Some fatty acids in release agents are unsaturated, similar to the unsaturated vegetable oils in margarine and cooking oils. In poorly formulated release agents fatty acids end up, unused, on the bottom of the container, especially when temperatures drop below 50 F. Test yours in a refrigerator or freezer.