so that it could be used in the Würzburg and Kassel directions. To make this possible, another first aid coach has been inserted behind transport wagon 1. By stationing a TuHi at Hildesheim Hbf and Kassel Hbf both directions of the high-speed link can be traversed via link lines. For that reason a unidirectional train is sufficient here. Between August 1990 and April 1991 eight more 212 or 214s were modified at AW Bremen und AW Kassel for the four other TuHi. Locomotives 212 033, 212 046, 212 235, 212 245, 212 246, 212 251, 212 260 and 212 277 were converted to Class 214, all retaining their original serial numbers. There is no difference any longer between locos 1 and 2, in order to be able to exchange them more easily, which is always necessary when carrying out routine maintenance. The former locomotive 2's from Würzburg and Fulda were fitted with the missing infra-red cameras in 1991 at AW Kassel. The cooling of the infra-red cameras is achieved now using the usual liquid air cylinders, which were swapped for the previously used liquid nitrogen flasks. After the serious train accident on 15 November 1992 at Northeim, when no TuHi was used, a new concept for rescue operations was introduced. Once the TuHi also became available for deployment away from the high-speed railway they became known as "emergency trains" (Rettungszüge or Rtz). All 13 engines of Class 214 were redesignated by the DB AG on 31 October 1994 to railway works vehicles of Class 714. Again the running numbers were retained. On 1 August 1996, however, they were given sequential numbers within Class 714, from 001 to 013. The locomotive with the lowest original number became 001 and the one with the highest became 013. Because only one reserve locomotive is available, DB AG converted another two engines in 1996/97 at Stendal: numbers 212 269 became 714 014 and 212 160 became 714 015. In addition to the renumbering, the TuHi/Rtz locos changed their livery. The first five TuHi locos still had the classic ocean blue and beige livery, the later eight engines were painted orient red. To achieve greater recognisability against the emergency wagon, the locos were painted in luminous red. Numbers 714 003, 714 008, 714 009, 714 011, 714 014 and 714 015 have this livery, as do the wagons in the Rtz at Würzburg, Fulda and