As early as 1900, the first specialised chemical tank wagons were developed for transporting chemical products. From the outset, they differed significantly from the tank wagons designed for transporting flammable liquids. A crucial safety feature of chemical tank wagons for acid transport was the absence of bottom valves, which helped to prevent accidental leakage of their hazardous cargo. Additionally, due to the high density of acids, these tanks were comparatively smaller than those used for flammable liquids.For the typical 8.8-metre-long wagons of the standardised interchangeable types introduced in the 1930s, a tank volume of between 10 and 12 m� proved to be the most economical solution. Depending on the manufacturing capabilities of the wagon builders, the tanks were either riveted or welded. However, the heating pans located in the lower section of the tanks were consistently produced using welding technology to ensure greater tightness and stability.The wagons, originally built from 1939 onwards for I.G. Farbenindustrie and the Wirtschaftliche Forschungsgesellschaft (Wifo), were largely transferred to the successor companies Bayer, BASF and VTG in the Federal Republic of Germany after the Second World War. In the German Democratic Republic, Deutsche Reichsbahn (the East German national railway) took possession of the wagons and leased them to state-owned enterprises, known as VEBs.After approximately 40 years of service, these wagons were gradually decommissioned from the mid-1970s onwards. The last chemical tank wagons of this type were finally retired in 1988.
