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Rail passenger behaviour invites ‘trap and drag’ incidents

Richards Roels, one of DNV’s human factors specialists, looks at new research relating to ‘trap and drag’ incidents.

Published: 1 March, 2018


‘Trap and drag’ refers to events where someone is caught in the doors of a train and dragged along the platform as the train departs.  Whilst very rare, these incidents are of great concern to the rail industry.  In the past few days independent investigators announced they were looking at a serious incident on London Underground. Train operators and investigators may benefit from recently published research into passengers’ understanding of door closing arrangements.

DNV Research into Passenger Response to Door Close Alarms
The 2017 research, undertaken on behalf of RSSB by DNV’s human factors specialists, found:

  • Two-thirds of passengers interviewed did not recognise the door close alarm as meaning ‘stand back’, with many taking it as a signal to board
  • If obstructed, most passengers believed doors would re-open like lift doors; this is leading to deliberate blocking of doors
  • Occasional leisure travellers are most at risk of injury
  • Doors that automatically close after a set time, e.g. to regulate train temperature, can confuse and startle passengers, causing a large proportion of door close injuries
  • There are wide variations in door close alarm durations and door speed. The assessment identified no preferred approach. Nor was there evidence that achieving consistency is key to improving behaviour.  However, enhancing on-board auditory and visual cues could help passengers make better boarding and alighting decisions.

One of the study’s recommendations was around raising passenger awareness. An initial RSSB press release had a big impact, reaching the national press (Evening Standard, Telegraph, and The Times). RSSB is also looking at longer term awareness-raising initiatives as well as the study’s other recommendations.

Further information
CCTV footage shows just how quickly these events unfold (BBC)

Click here for the Research Brief and to request access to the main report (RSSB)

See more on DNV’s rail safety studies (DNV)

3/1/2018 8:00:00 AM