The trains were designed with Channel Tunnel safety in mind, and consist of two independent "half-sets" each with its own power car.[6][59] In the event of a serious fire on board while travelling through the tunnel, passengers would be transferred into the undamaged half of the train, which would then be detached and driven out of the tunnel to safety.[178] If the undamaged part were the rear half of the train, this would be driven by the Chef du Train, who is a fully authorised driver and occupies the rear driving cab while the train travels through the tunnel for this purpose.[179]