Grinding paste residue and other organic residue on the brake resistor grid of a London Underground Northern Line train caused smoke and a burning smell which prompted passengers to self-evacuate at Clapham Common on 23 May 2023.
The Rail Accident Investigation Branch’s probe found that the train was probably using a high level of rheostatic braking as it approached the station, which would have contributed to heat build-up in the resistor grid.
The self-evacuation happened at around 17.43 when a passenger emergency alarm activation caused a train departing from Clapham Common station to stop with two cars in the tunnel and four next to the platform. Around 100 of the train’s estimated 500 passengers evacuated onto the platform through interconnecting doors between the cars and the train’s windows, some of which were broken by passengers. Station staff started opening the train’s doors manually around four-and-a-half minutes after the train stopped. Minor injuries were reported by ‘a few’ passeng…
