He said health and safety was the industry's top priority and strict policies were in place.
"We must all take actions to prevent accidents, which injure people while they are at work and we must never be complacent."
He said downing tools was an established practice for the industry to refocus their people on health and safety.
Higgins contractors Haki Hika, David Eparaima and Dudley Soul Raroa were clearing a culvert on State Highway 2 near Pikowai when they were killed in a crash involving four trucks.
One person has been charged.
Last month a 25-year-old Fulton Hogan worker was killed after being struck by a work vehicle while carrying out resurfacing work on State Highway 1 at Wellington.