1.1 本试验方法涵盖了确定粉尘层热表面点火温度的实验室程序，即测量粉尘层自热的最低温度。该测试包括在热板上加热的粉尘层。 2. , 3. 1.2 从该试验方法获得的数据提供了粉尘层热表面点火温度的相对测量值。 1.3 本试验方法应用于测量和描述受控实验室条件下材料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危险。 然而，本试验方法的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产品火灾风险评估相关的所有因素。 1.4 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 第节给出了具体的预防说明 8. . ====意义和用途====== 5.1 本试验方法适用于粉尘和粉末，并提供了进行实验室试验的程序，以评估粉尘层的热表面点火温度。 5.2 测试数据在确定工业厂房、矿山、制造过程以及材料使用和储存位置的安全操作条件方面具有价值。 5.3 由于点火温度随层厚变化，一种厚度下的测试数据可能不适用于所有工业情况（见 附录X1 ). 不同层厚的测试可提供一种推断较厚层的方法，如下所示，用于匹兹堡烟煤粉 ( 2. ) . 不同层厚下的层点火数学模型如Ref。 ( 3. ) . 层厚度，mm 热表面点火温度，°C 6.4 300 9.4 260 12.7 240 25.4 210 5.4 这种热板试验方法允许从粉尘层顶面损失热量，因此通常会使材料的点火温度高于试验方法 E771 ，这是一个更绝热的系统。 5.5 粉尘层的本试验方法通常会给出比试验方法更低的点火温度 E1491 ，表示尘埃云。在监测几分钟到几小时的时间段时，确定层点火温度，而尘云仅暴露在熔炉中几秒钟。 注1: 关于层点火的许多文献数据实际上来自加热炉中的篮子 ( 4. ) ，称为改进的戈伯特-格林沃尔德炉试验。其他数据来自非标准热板 ( 5- 9 ) . 5.6 有关本试验方法的重要性和使用的其他信息，请参阅。 ( 10 ) .

1.1 This test method covers a laboratory procedure to determine the hot-surface ignition temperature of dust layers, that is, measuring the minimum temperature at which a dust layer will self-heat. The test consists of a dust layer heated on a hot plate. 2 , 3 1.2 Data obtained from this test method provide a relative measure of the hot-surface ignition temperature of a dust layer. 1.3 This test method should be used to measure and describe the properties of materials in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire hazard risk of materials, products, or assemblies under actual fire conditions. However, results of this test method may be used as elements of a fire risk assessment that takes into account all of the factors that are pertinent to an assessment of the fire hazard risk of a particular end use product. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8 . ====== Significance And Use ====== 5.1 This test method is applicable to dusts and powders, and provides a procedure for performing laboratory tests to evaluate hot-surface ignition temperatures of dust layers. 5.2 The test data can be of value in determining safe operating conditions in industrial plants, mines, manufacturing processes, and locations of material usage and storage. 5.3 Due to variation of ignition temperature with layer thickness, the test data at one thickness may not be applicable to all industrial situations (see Appendix X1 ). Tests at various layer thicknesses may provide a means for extrapolation to thicker layers, as listed in the following for pulverized Pittsburgh bituminous coal dust ( 2 ) . Mathematical modeling of layer ignition at various layer thicknesses is described in Ref. ( 3 ) . Layer Thickness, mm Hot-Surface Ignition Temperature, °C 6.4 300 9.4 260 12.7 240 25.4 210 5.4 This hot plate test method allows for loss of heat from the top surface of the dust layer, and therefore generally gives a higher ignition temperature for a material than Test Method E771 , which is a more adiabatic system. 5.5 This test method for dust layers generally will give a lower ignition temperature than Test Method E1491 , which is for dust clouds. The layer ignition temperature is determined while monitoring for periods of minutes to hours, while the dust cloud is only exposed to the furnace for a period of seconds. Note 1: Much of the literature data for layer ignition is actually from a basket in a heated furnace ( 4 ) , known as the modified Godbert-Greenwald furnace test. Other data are from nonstandardized hot plates ( 5- 9 ) . 5.6 Additional information on the significance and use of this test method may be found in Ref. ( 10 ) .