US-based commuter rail operator Metrolink plans to award a $120m contract to Parsons Transportation Group for the implementation of collision avoidance technology across its rail network.

Under the contract, Parsons will manage and integrate positive train control (PTC) technology on the rail operator’s 512-mile system.

The system will consist of on-board computers, display screens, GPS tracking and radios for the 57 cab cars and 52 locomotives, and a stop enforcement system at 476 signals.

It also features six county specialised communication systems to link the wayside signals, trains and the centralised dispatch office.

The technology will be put into service by 2015 as a key component of the US rail safety improvement act of 2008.