The Office of Transport Safety Investigations (OTSI) has launched an inquiry into the fatal bus crash on Wine Country Drive that killed 10 people on June 11.
The scope of the investigation into the rollover of coach 4666MO at Greta will examine the sequence of events leading up to the collision, road design, conditions, signage and visibility.
OTSI acting chief investigator Kerry Russell said the company offered its deepest condolences to the families, friends and communities of those impacted by the crash.
She said the aim of the independent investigation was to enhance transport safety by sharing safety lessons and insights.
"The OTSI will examine the usage of passenger restraint devices, the roadworthiness, crashworthiness and survivability of the vehicle and operation accreditation and safety management systems.
"We use a 'no-blame' approach to identify and understand contributing safety factors and underlying issues. It does not assign fault or determine liability in relation to the matters it investigates," she said.
A report will be published and tabled in NSW Parliament by the Minister for Transport.
The investigation follows depot raids by police investigators and National Heavy Vehicle Regulator inspectors that involved checking 20 buses at Linq Busline depots in Wyong and East Gresford.
Seven defect and two infringement notices were issued after a cracked windscreen, oil leaks, inoperative seatbelts and vehicle lights and insecure seats were found.
"The joint operation involved a comprehensive audit of documentation relating to fatigue, driver management, vehicle servicing and maintenance records, and safety management systems," a police statement issued on Thursday night said.
Linq said in a statement that "one major defect identified in the fleet has been rectified" and minor defects were being rectified in accordance with the timelines set by the regulator
The insurer managing the crash compensation claims is being urged to ensure extended family and friends of the victims receive support.
Only those directly involved in the crash, or who had suffered psychological trauma due to the death or severe injury of a close relative, are eligible for support under the state's compulsory third-party scheme.
Slater and Gordon lawyer Doug Williams called on the insurer to show compassion to those who had suffered due to the crash.
"It's (the scheme) so limited that the close friends and the extended family as well as members of the small community where many of those killed lived would be ineligible to claim treatment," he said.
Anyone wanting to support the families and injured with a donation is encouraged to visit rawcs.org.au.
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