Gates Fail, Lack of Communication About Design Changes

Boom gates fail to activate in train incident in Australia due to absence of information exchange regarding interim design changes.

A range of safety actions have been taken, or are underway, to address issues highlighted in the investigation of boom gates failing to operate at a pair of level crossings in an incident at Werribee, southwest of Melbourne, Australia.

On December 4, 2020, a train hauling containerized freight passed over the Werribee Street and Cherry Street level crossings, without either crossing’s boom gates activating — what caused the gates to fail?

At one crossing, cars passed less than two seconds in front of the train as it approached.

An investigation by Victoria’s Office of the Chief Investigator, conducted on behalf of the Australian Transport Safety Bureau (ATSB), has yielded a number of safety issues relating to the management and communication of changes during complex infrastructure projects.

The investigation’s final report explains that the incident was associated with electrical circuit isolation arrangements for level crossing removal signaling works.

“The design for the isolation of these circuits was changed two days before work began, and this was not effectively reflected in program documentation, nor effectively disseminated to all those potentially affected,” Chief Investigator Mark Smallwood said.

As part of the isolation, two fuses which were supposed to be ‘removed and secured’ were instead disconnected, but folded out, with one end remaining in the fuse holder.

“A few days later, a different set of workers – who were not familiar with the isolation arrangement – rotated the two fuses back into place for the purpose of testing,” Mr Smallwood explained.

“This reconnection, combined with temporary jumper wires installed as part of the isolation, prevented the level crossing protection equipment from operating when the train approached.”

It was found that there was probably no independent check of the isolation arrangements as originally installed. An earlier internal audit of the project also identified instances of testers in charge checking their own work.

“This occurrence highlights the importance of considering the implications of late design changes, updating plans and programs, and ensuring all affected parties have a clear understanding of the implications of their work activities,” Mr. Smallwood said.

“This is particularly the case in complex projects that involve consortia, contractors, subcontractors, and the responsible rail infrastructure manager.”

After the incident, the project alliance in charge of the level crossing removal – which includes operator Metro Trains Melbourne – took several safety actions, including updating of assurance frameworks and associated procedures, and awareness initiatives.

“These actions should address identified safety issues in testing and commissioning practices and assurances,” Mr. Smallwood remarked.

The final report also notes Metro Trains Melbourne is contributing to the development of consistent signaling practices and enhanced competency frameworks across all of its major projects.

“The work of Victoria’s Signalling Strategy Taskforce, in which Metro Trains Melbourne is an active participant, has the potential to provide an industry-wide framework to address safety issues like those identified in this investigation,” Mr. Smallwood concluded.

Read the ATSB report: Level crossing irregularities involving freight train 3PM7, Werribee, Victoria, on 4 December 2020, publication date: 16/08/2024.