ISO 3008-4:2021 pdf download – Fire resistance tests — Door and shutter assemblies — Part 4: Linear joint fire seal materials used to seal the gap between a fire door frame and the supporting construction. 5.2 Specimen size Each test specimen shall be a minimum of 900 mm in length. In instances where the distance between anchors for the fire door frame exceeds 900 mm, the test specimen shall be of a length such that the combined length of linear joint fire seal, door frame and supporting construction is at least equivalent to the maximum distance between door frame anchors....