Review of Fire Tests on Seats for Passenger Coaches and the Materials Used in Them

This study shows how the fire regulations for railway seats used in international traffic have changed over the last 30 years. In the past, a paper cushion was used as a flame source, and today, a 15 kW burner is used; consequently, the requirements have increased. In the paper cushion test, a foam with a density of between 60 and 95 kg/m3, a flame-retardant fleece, and a cover fabric was usually sufficient in terms of fire safety. Today, a high-quality flame-retardant foam is necessary to meet the requirements for flaming with the 15 kW burner. Two comparable seat structures show very different heat release and smoke formation in the paper cushion test due to different foam additives. If high-quality flame-retardant foams with a cover fabric are used for the 15 kW flame treatment, the results of the two test institutes show good agreement. If the seats that meet the requirements of the paper cushion test are flamed using the 15 kW treatment, they can catch fire and thus exhibit very different heat release rates, as the CERTIFER interlaboratory test with 12 participating test institutes shows. The heat release of old and new leather was examined, and it was found that the flame retardant applied to the leather surface appeared to have aged over the years and that the flame retardant was therefore no longer effective. The heat release of flame-retardant foams with a cover fabric was measured using irradiation with a cone calorimeter and flame treatment. Very different curves were observed, which means that it is not possible to draw simple conclusions about the heat release during flame treatment from the cone measurement.