An engineering possession was established on the night of 27/28 October 2012 between Stirling and Blackford in Scotland. A possession is an arrangement whereby the line is closed to normal traffic to allow engineering staff to carry out work. Several items of maintenance work were planned to be carried out in this possession and these items were grouped into four work sites. At 07:04 hrs the person in charge of the possession authorised the reopening of the line to normal traffic when only three of the work sites had completed their work and were clear of the line. Work in the fourth work site was still ongoing when the line reopened to traffic.
Seven members of staff were working on the line along with a road-rail excavator and trailer. This work continued for an hour after the line was reopened. No collision occurred as there were no trains scheduled at the time, but there were no measures in place to prevent a train from being signalled through the work site.
The person in charge of the possession did not record details of the work site on the possession form. He was under some stress from events outside of his work at the time and this may have affected his performance. Other probable factors were late alterations to the work sites within the possession and the way in which the briefing pack for the possession was presented.
The RAIB has identified three learning points related to the use of the possession arrangements form, the way in which possession information packs are prepared and dealing with staff under stress.