ISO 871:2022

This document specifies a laboratory method for determining the flash-ignition temperature and spontaneous-ignition temperature of plastics using a hot-air furnace. It is one of a number of methods in use for evaluating the reaction of plastics to the effects of ignition sources.
NOTE       Information on additional ignition methods can be found in ISO 10093.
This method does not give a direct measure of the combustibility or rate of burning of a material or any definition of the safe upper limit of temperature for the plastics in use, and it is inappropriate to use it alone to describe or appraise the fire hazard or fire risk of materials, products or assemblies under actual fire conditions. However, results of this test are suitable for use as elements of a fire hazard or fire risk assessment which takes into account all of the factors pertinent to an assessment of the fire hazard of a particular end use.
Tests made under conditions of this method are potentially of considerable value in comparing the relative ignition characteristics of different materials. Values obtained represent the lowest ambient air temperature that has the potential to cause ignition of the material under the conditions of this test. Test values are expected to rank materials according to ignition susceptibility under actual use conditions.
The results of this test method are not intended for fire safety engineering calculations.