The 4WD PRO-4X comes with heavy-duty off-road equipment.

First port to conduct air emissions testing of its off-road equipment (2000)

But it would still be feasible in some forests to extract timber using helicopters or off-road logging equipment.

But off-road equipment produces more fine-particle pollution than all those vehicles combined.

Diesel fuel used in off-road equipment often has sulfur concentrations of 3,000 parts per million.

NO2 forms quickly from emissions from cars, trucks, buses, power plants, and off-road equipment.

Plant equipment and off-road equipment are off, after remaining relatively strong.

"There are something like 1,763 manufacturers of off-road equipment, compared to 22 or so for on-highway vehicles," said Allen Schaeffer, the group's executive director.

Back in New Zealand he was design engineer for Rowe Engineering, designing off-road equipment and heavy machinery.

The test truck had a jittery ride on most roads, partly because of its off-road equipment.