1.1本标准为耐火试验响应标准。 1.2本试验方法通过测量在正常通风条件下，当校车座椅样品经受指定的燃烧点火源时的特定火灾试验响应来评估校车中使用的软垫座椅的燃烧行为。 1.3点火源为燃气燃烧器。 1.4本防火试验主要用于区分暴露于点火源时会完全卷入火灾的产品与不会卷入火灾的其他产品。 1.5获得的数据描述了座椅总成在特定点火源下的燃烧行为，直到所有燃烧停止。 1.6本试验方法不提供在规定条件以外的火灾条件下软垫座椅防火性能的信息。 1.7燃烧行为尽可能通过照片或视频记录进行视觉记录。 1.8以国际单位制或英寸-磅单位表示的数值应单独视为标准值。每个系统中规定的值可能不是精确的等效值；因此，每个系统应相互独立使用。将两个系统的值合并可能会导致不符合标准。 1.9 本标准用于测量和描述材料、产品或组件在受控条件下对热量和火焰的响应，但其本身并不包括在实际火灾条件下对材料、产品或组件进行火灾危险或火灾风险评估所需的所有因素。 1.10 火灾测试本身就很危险。在进行这些测试时，应采取适当的人员和财产保护措施。 1.11 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。 ====意义和用途====== 在本试验方法中，在方形燃气燃烧器点火后，评估校车座椅总成的火灾试验响应特性。 该试验方法在概念上类似于目前使用的火灾试验，并已使用多年，作为校车座椅易燃性试验的行业标准（见附录X1）。然而，在本试验方法中，纸袋已被作为点火源的气体燃烧器所取代。 美国联邦政府发布了适用于道路车辆内部材料的易燃性测试FMVSS 302。FMVSS 302仍然是评估校车座椅防火测试响应特性的唯一监管测试。 ASTM已发布测试方法 D5132 为了提供执行FMVSS 302的更标准化方法。 与FMVSS 302联邦法规测试相比，本文件中描述的测试方法对校车座椅提出了更高的挑战。 因此，在本试验中表现合格的任何座椅总成都可能满足FMVSS 302的要求。 很明显，与剧烈燃烧且质量损失高的座椅总成相比，在本试验中表现出很少或没有火焰传播、火焰熄灭时间短和质量损失小的座椅总成在实际火灾情况下可能表现出更好的性能。 该测试主要用于区分暴露在这些火灾条件下会完全卷入火灾的产品和不会卷入火灾的其他产品。

1.1 This is a fire-test-response standard. 1.2 This test method assesses the burning behavior of upholstered seating used in school buses by measuring specific fire-test responses when a school bus seat specimen is subjected to a specified flaming ignition source under normally ventilated conditions. 1.3 The ignition source is a gas burner. 1.4 This fire test is primarily useful to distinguish products that, when exposed to an ignition source, will become fully involved in fire from other products that will not. 1.5 Data are obtained describing the burning behavior of the seat assemblies from a specific ignition source until all burning has ceased. 1.6 This test method does not provide information on the fire performance of upholstered seating in fire conditions other than those conditions specified. 1.7 The burning behavior is visually documented by photographic or video recordings, whenever possible. 1.8 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. 1.9 This standard is used to measure and describe the response of materials, products, or assemblies to heat and flame under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products or assemblies under actual fire conditions. 1.10 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these tests. 1.11 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. ====== Significance And Use ====== In this test method fire test response characteristics of a school bus seat assembly are assessed following ignition by a square gas burner. This test method is similar in concept to a fire test currently used, and which has been in such use for many years, as the industry standard for flammability testing of school bus seats (see Appendix X1). However, in this test method the paper bag has been replaced by a gas burner as the ignition source. The US federal government has issued a flammability test applicable to interior materials in road vehicles, FMVSS 302. FMVSS 302 remains the only regulatory test for assessing fire-test-response characteristics of school bus seats. ASTM has issued Test Method D5132 in order to provide a more standardized way of conducting FMVSS 302. The test method described in this document provides a significantly higher challenge to school bus seats than the FMVSS 302 federal regulatory test. Therefore, any seat assembly that performs acceptably in this test is likely to meet the requirements of FMVSS 302. It is clear that those seat assemblies that exhibit little or no flame spread, short times to flame extinction and little mass loss in this test are likely to exhibit improved performance in an actual fire situation compared to seat assemblies that burn vigorously and have high mass loss. This test is primarily useful to distinguish products that, when exposed to these fire conditions, will become fully involved in fire from other products that will not.