ISO/TR 24679-4:2017根据ISO 24679-1中给出的方法，提供了与十五层钢框架建筑耐火性评估相关的消防工程应用。本文件描述了采用的过程，该过程遵循与ISO 24679-1中规定的步骤相同的步骤。本文件的附件给出了根据建筑物特定消防安全工程程序的结果，针对最严重火灾场景获得的详细评估结果。 在本例中，就耐火性而言，应用于办公楼的消防安全工程考虑了特定的设计火灾场景以及相应的火灾发展。 它考虑了充分发展的隔间火灾。在现实情况下，灭火系统的激活和/或消防队的干预是可以预期的，但没有考虑到它们的有利影响。应注意的是，这些严重火灾场景是出于防火目的选择的。 计算公式中未明确考虑整体结构性能，但隐含了整体结构性能。由于示例中的建筑位于地震区，因此主要结构构件彼此刚性连接。存在从加热元件到冷周围元件的荷载再分配，但在设计计算中未考虑。 通过这种方法，设计是保守的，而安全检查的过程则大大简化和清晰。因此，所有的计算都是通过显式代数公式进行的。

ISO/TR 24679-4:2017 provides a fire engineering application relative to the fire resistance assessment of a fifteen-storey steel framed building following the methodology given in ISO 24679-1. This document describes the adopted process which follows the same step by step procedure as that provided in ISO 24679-1. The annexes of this document present the detailed assessment results obtained for the most severe fire scenarios on the basis of the outcome of this specific fire safety engineering procedure for the building. The fire safety engineering applied in this example to the office building with respect to its fire resistance considers specific design fire scenarios as well as the corresponding fire development. It takes into account fully-developed compartment fires. In realistic situations, activation of fire suppression systems and/or intervention of fire brigade are expected, but their beneficial effects are not taken into account. It should be noted that these severe fire scenarios have been selected for fire resistance purposes. Global structural behaviour is not explicitly considered, but implicitly included in the calculation formulae. Since the building of the example is located in a seismic region, principal structural elements are rigidly connected to each other. Load redistribution from heated elements to cold surrounding elements exists, but it's not taken into account in the design calculations. By this approach, design is conservative, while the process of safety checking is greatly simplified and clear. As a result, all the calculations were carried out by explicit algebraic formulae.