Arc Infrastructure’s procedures included no requirement for a network control officer (NCO) to make an emergency call and advise potentially ‘at risk’ trains that another nearby train had overrun its limit of authority.
The ATSB is satisfied that the action being taken by Arc Infrastructure has reduced the risk of this safety issue.
Arc Infrastructure Network Safeworking Rules and Procedures – Overrun of Limit of Authority, Rule Number 6001, was revised on 3 February 2020. This revision included a requirement for the network control officer (NCO) to make an emergency radio call following rail traffic overrunning its limit of authority.
This change had the effect of requiring the NCO to make an emergency radio call where other rail traffic or track workers may be in conflict with the rail traffic that has exceeded its limit of authority. The change was communicated to relevant workers via a safety directive.
In addition, Arc Infrastructure introduced a training course titled ‘Apply safety critical communications in a rail environment’. The training included a requirement to make an emergency radio call to all rail traffic on the rail corridor following the declaration of an emergency situation where rail traffic had exceeded its limit of authority This training was completed by all NCOs on 21 August 2020.
In November 2022, Arc Infrastructure further updated Rule 6001 to remove the phrase ‘at risk’ as it was a subjective determination. As a result of the change, Rule 6001 required that, when there was an overrun of limit of authority, the NCO must make an emergency radio call advising all other rail traffic movements (that were at, or approaching, the location where the overrun of authority occurred) to stop.
