The incident soon after midnight on Thursday followed a callout to a wheat paddock at Moree on Tuesday where paramedics treated a 22-year-old man who suffered burns to his right arm and leg after his ute caught fire.

NSW Ambulance Superintendent Brad Porter said each year paramedics attended people injured during harvest.

He said the incidents reflected people working "extremely long hours", late into the night and in the dark.

Superintendent Porter said in some cases patients were itinerant workers who were not completely familiar with the vehicles and machinery they were operating.

"This can include massive harvesters, road train trucks, and tractors with big chaser bins that are pulling 40 tonnes of grain," he said.

"These key aspects are leading to some high-risk situations where people have the potential to be maimed and critically injured."

Superintendent Porter urged workers to be fully briefed before operating heavy machinery, and to be mindful of fatigue and personal safety.