ROAD safety campaigner Mark Arena believes concrete barriers should be installed on all major two-lane roads.
He made the comments in the wake of the tragic crash that killed four young people on the Pacific Highway at Newrybar on Tuesday night.
"Concrete barriers prevent head on collisions, which are a big problem across the state. People don't walk away," he said.
Mr Arena said a physical barrier would also have prevented the accident at Newrybar where it appears the Hyundai sedan driven by Jessica Camidge crossed over a double white line in order to overtake a truck.
"It (a barrier) stops people crossing the road," he said.
"Normally you wait until there is an overtaking section to overtake, but in this case they would have been prevented from making the overtaking manoeuvre had there been a concrete barrier - it would have been impossible."
Mr Arena estimated that concrete barriers would cost around $300 per metre, which he agreed was a big expense.
However, it would save lives and also reduce the costs associated with hospitals, emergency services and social workers for victim's families.
Mr Arena has advised the RMS and the Centre for Road Safety and has been a strong advocate for numerous road safety measures in NSW.