SCHEDULE 4U.K.Types of accidents and incidents occurring within the Channel Tunnel System that must be notified to the Rail Accident Investigation Branch immediately and by the quickest means available

3.  A collision that occurs on any line other than a siding, between rolling stock and—U.K.

(a)other rolling stock;

(b)an object capable of causing damage to or derailment of the rolling stock; or

(c)a buffer stop.