1.1 本试验方法包括在均匀加热的容器中，在大气压下测定空气中液体化学品的冷热火焰自燃温度。 注1: 在某些限制范围内，本试验方法也可用于确定在低于试验温度的温度下容易熔化和蒸发的固体化学品的自燃温度，以及在大气压力和温度下为气体的化学品的自燃温度。 注2: 循环研究后，测试方法 D2155 1978年停止使用，并被试验方法E659取代。另请参见 附录X2 . 1.2 本标准应用于测量和描述材料、产品或组件在受控实验室条件下对热和火焰的响应特性，不应用于描述或评估材料、产品或组件在实际火灾条件下的火灾危险或火灾风险。 然而，该测试结果可作为火灾风险评估的要素，该评估考虑了与特定最终用途火灾危险评估相关的所有因素。 ====意义和用途====== 5.1 自燃就其本质而言，取决于材料的化学和物理特性以及用于测定其的方法和设备。给定方法的自燃温度不一定代表给定材料在空气中自燃的最低温度。使用的容器体积特别重要，因为在较大的容器中可以实现较低的自燃温度。（参见 附录X2 .) 容器材料也是一个重要因素。 5.2 本试验方法确定的温度是指空气氧化导致点火的温度。预计这些温度会随试验压力和氧气浓度而变化。 5.3 本试验方法不用于评估能够放热分解的材料。对于此类材料，点火取决于分解的热特性和动力学特性、样品质量和系统的传热特性。 5.4 本试验方法可用于在试验温度下熔化和蒸发或容易升华的固体化学品。点火时，不应存在冷凝相（液体或固体）。 5.5 本试验方法的目的不是测量在试验温度下固体或液体材料（例如木材、纸张、棉花、塑料和高温）的自燃温度- 沸点化学品）。此类材料将在烧瓶中热降解，累积的降解产物可能会点燃。 5.6 经适当修改后，本试验方法可用于在大气温度和压力下为气态的化学品。 5.7 本试验方法主要用于液体化学品，但已用于测试易蒸发的固体。操作员负责将本试验方法扩展到热稳定性、沸点或降解特性未知的固体。

1.1 This test method covers the determination of hot- and cool-flame autoignition temperatures of a liquid chemical in air at atmospheric pressure in a uniformly heated vessel. Note 1: Within certain limitations, this test method can also be used to determine the autoignition temperature of solid chemicals which readily melt and vaporize at temperatures below the test temperature and for chemicals that are gaseous at atmospheric pressure and temperature. Note 2: After a round robin study, Test Method D2155 was discontinued, and replaced by Test Method E659 in 1978. See also Appendix X2 . 1.2 This standard should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use. ====== Significance And Use ====== 5.1 Autoignition, by its very nature, is dependent on the chemical and physical properties of the material and the method and apparatus employed for its determination. The autoignition temperature by a given method does not necessarily represent the minimum temperature at which a given material will self-ignite in air. The volume of the vessel used is particularly important since lower autoignition temperatures will be achieved in larger vessels. (See Appendix X2 .) Vessel material can also be an important factor. 5.2 The temperatures determined by this test method are those at which air oxidation leads to ignition. These temperatures can be expected to vary with the test pressure and oxygen concentration. 5.3 This test method is not designed for evaluating materials which are capable of exothermic decomposition. For such materials, ignition is dependent upon the thermal and kinetic properties of the decomposition, the mass of the sample, and the heat transfer characteristics of the system. 5.4 This test method can be employed for solid chemicals which melt and vaporize or which readily sublime at the test temperature. No condensed phase, liquid or solid, should be present when ignition occurs. 5.5 This test method is not designed to measure the autoignition temperature of materials which are solids or liquids at the test temperature (for example, wood, paper, cotton, plastics, and high-boiling point chemicals). Such materials will thermally degrade in the flask and the accumulated degradation products may ignite. 5.6 This test method can be used, with appropriate modifications, for chemicals that are gaseous at atmospheric temperature and pressure. 5.7 This test method was developed primarily for liquid chemicals but has been employed to test readily vaporized solids. Responsibility for extension of this test method to solids of unknown thermal stability, boiling point, or degradation characteristics rests with the operator.