The fire point of a fuel is the temperature at which it will continue to burn for at least 5 seconds after ignition by an open flame. At the flash point, a lower temperature, a substance will ignite briefly, but vapor might not be produced at a rate to sustain the fire. Most tables of material properties will only list material flash points, but in general the fire points can be assumed to be about 10 °C higher than the flash points. However, this is no substitute for testing if the fire point is safety critical. [1]
Fire point is only useful for determining if a liquid is no longer regulated by NFPA 30 or DOT. So trying to use fire point for gases, solids, or other hazard classes like organic peroxides, oxidizers, corrosives, or toxics will not provide you benefit. In fact, if you attempt to perform a fire point test on a organic peroxide or oxidizer, ensure your health insurance is paid and you know the location of closest burn center if you decide to do this beyond the laboratory level. I mention this because you wrote looking at chemicals, and fire point testing is only limited to liquids classified as either flammable or combustible.
Some formulations of flammable or combustible liquid will exhibit a flash point but contain a high concentration of water. This is especially true for many consumer sanitation products. Fire point testing allows one to confirm that combustion will not be sustained for more than 5 seconds even though the liquid exhibits a flash point. If a liquid does not exhibit a fire point, it is exempt from regulation by NFPA 30 and US DOT.
