Within the context of the preparation of fire safety certificates for industrial buildings methods of fire protection engineering are frequently used. Computational fluid dynamics represents instruments for these methods and is used for modeling and calculation of fire scenarios. In this paper a method of fire technological measurement, which is based on computational fluid dynamics and structural mechanics, was used for an industrial building. Unsteady temperature profiles were used as an input value for the building component calculation. The outcomes were finally used for the calculation of the equivalent length of fire, which is an important term to reckon the fire resistance rating of building components.