What are the train working procedures in case of accidents, derailments, etc.?
(Naturally, there are well-defined rules on obtaining medical help and emergency services, etc. in the case of accidents, and assisting injured people and preventing further injury or death takes the highest priority. But here we focus only on train working guidelines which come into play for accidents.) The general principle is to protect the train that has been involved in the accident: this is done by ensuring the block section remains closed to further traffic, and by providing additional temporary signals in the form of flares, detonators, banners or hand signals (lamp/flag), etc. to prevent any train from colliding with the train involved in the accident in case signals have been pulled off at the station at either end, or in case there is a signal failure due to the track circuit not being tripped. Detonators are placed as follows: one 600m from the train, and three about 1200m from it, 10m apart (on the other gauges the distances are 400m and 800m). If the section is a double l
