Bay of Plenty road policing manager Kevin Taylor says installing centreline barriers on high-risk roads would help prevent head-on crashes.
His comments came after a deadly weekend on the roads.
Ten people died in a series of crashes - the most lives claimed in a single weekend for several years.
One was on State Highway Two, at Te Puna, in which three people were killed and seven others injured.
Inspector Kevin Taylor said excessive speed did not appear to have played a part in the crash, and a part of the highway had its speed limit reduced to 90 kilometres an hour more than five years ago.
He said installing road barriers would make the biggest difference in preventing crashes.
"Any road in New Zealand where you are protected from oncoming traffic by four inches of paint on the road's surface does not afford you much protection when things go wrong.
"Centreline barriers in appropriate places would prevent head-on collisions," he said.
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