Line blockages that should be full T3 Possessions

Our Ref: HSR/2/15
Head Office Circular: NP/203/17
28th November 2017


The Secretary

Dear Colleague

Line blockages that should be full T3 Possessions

Further to Head Office Circular IR/539/17, 25th November 2017 the NIOC of Signalling and Operations Grades considered a resolution concerning a growing trend within Network Rail whereby work on the infrastructure is being planned using the WON or GZAC process and utilising the Line Blockage arrangements rather than a full T3 possession. The consequences of this are twofold. Firstly, Maintenance staff and contractors have a less than optimal level of protection/separation from moving trains. Secondly, Signalling staff are placed under pressure to find margins for line blockages during their normal working duties rather than having this workload planned appropriately.

As instructed by the National Executive Committee I will be raising this matter with the company but concrete examples of this process being adopted need to be obtained. This matter must be raised at Branch and Regional Council meetings and any information gained during those discussions must be fed-back to Head Office Health and Safety section via e-mail to or Ideally we require GZAC or WON numbers, date, time and location.

We can then use this information to feedback to Network Rail and ensure that the pressure on Signaller workload is eased and our Maintenance and Contractor members are given the full protection of detonators and T3 possessions.

Yours sincerely
Mick Cash
General Secretary