A detrainment device is equipment on a rail vehicle that provides an evacuation route for the passengers. It usually consists of a set of steps or a ramp, located at a doorway, allowing passengers to leave the vehicle in an emergency, vehicle breakdown or accident.
A detrainment device is moved from a stored location into an operational position, usually above the coupler at the end of a passenger car. A detrainment device may consist of a manually placed, hinged, foldable or telescopic ladder or ramp. A detrainment device may allow evacuation to track level, or to a coupled railcar. A detrainment device may be fitted with handrails.
In other cases, evacuation may be via the vehicle passenger side doors to a trackside walkway in a tunnel, without the use of a detrainment device.
Examples of the main types of detrainment device currently in service include:
User trials on prototype equipment in controlled conditions have indicated that a wide detrainment ramp will allow the evacuation of 2500 passengers in 28 minutes[10] if the ramp, its handrails and the cab and saloon throughways are correctly specified. Modern detrainment step systems can detrain one person every two seconds.