对火反应试验 火焰扩散 第4部分：垂直方向样品的垂直火焰的中级试验

[中文适用范围]： ISO 5658 的本部分规定了一种中等规模的测试方法，用于测量垂直位置产品样本上火焰的垂直蔓延（向上和向下）。 还可以获得横向扩展的度量。 它提供了适合比较材料、复合材料或组件性能的数据，这些材料、复合材料或组件在建筑应用中用作墙壁或其他垂直方向产品的暴露表面。 一些具有异形表面的产品也可以使用代表产品最终使用条件的修改程序进行测试。 2 向上的火焰蔓延不限于垂直表面。 人们认识到，在没有任何外部通风的情况下，在与水平面成大于 20° 的表面上也可能出现增强形式的向上、风助火焰蔓延。 这种类型的火焰蔓延可以发生在平面倾斜表面和阶梯表面（例如楼梯）中。 在这些情况下，火焰蔓延可能会变得非常迅速，并可能在楼梯等逃生通道中造成严重问题。 当评估阶梯或倾斜表面材料时，使用垂直火焰蔓延测试可能比样本水平测试更合适。 3 ISO 5658的本部分适用于在受控实验室条件下，在非冲击引燃火焰存在的情况下，测量和描述材料、产品、复合材料或组件对辐射热的响应特性。 热源可以被认为是代表单个燃烧物品，例如外壳内的废纸箱或软垫椅子，并且这种情况通常被认为适用于火灾的早期发展阶段（参见 ISO/TR 11696-1和 ISO/TR 11696-2）。 ISO 5658的这一部分不应单独用于描述或评估材料、产品、复合材料或组件在实际火灾条件下的火灾危险或火灾风险。 [外文原描述]： 1.1 This part of ISO 5658 specifies an intermediate-scale method of test for measuring the vertical spread (upward and downward) of flame over a specimen of a product orientated in the vertical position. A measure of lateral spread can also be obtained. It provides data suitable for comparing the performance of materials, composites or assemblies, which are used as the exposed surfaces of walls or other vertically orientated products in construction applications. Some products with profiled surfaces can also be tested with a modified procedure representative of the end-use conditions of the product. 1.2 Upward flame spread is not limited to surfaces which are vertical. It is recognized that an enhanced form of upward, wind-aided flame spread can also occur on surfaces at an angle greater than 20° from the horizontal without any external ventilation. This type of flame spread can occur in both planar sloping surfaces and stepped surfaces such as stairs. Flame spread in these situations can become very rapid and can cause serious problems in escape ways such as staircases. When assessing stepped or sloping surface materials, it may be more appropriate to use a vertical flame spread test rather than a test in which the specimen is horizontal. 1.3 This part of ISO 5658 is applicable to the measurement and description of the properties of materials, products, composites or assemblies in response to radiative heat in the presence of non-impinging pilot flames under controlled laboratory conditions. The heat source may be considered to represent a single burning item such as a wastepaper bin or an upholstered chair within an enclosure, and this scenario would generally be considered to apply during the early developing stage of a fire (see ISO/TR 11696-1 and ISO/TR 11696-2). This part of ISO 5658 should not be used alone to describe or appraise the fire hazard or fire risk of materials, products, composites or assemblies under actual fire conditions.