Three rural fire volunteers have survived being caught in an out of control fire in northern New South Wales.

In under a minute, a grass fire went from 30 centimetres to three metres high.

One crew member sheltered within the fire truck whilst two others on the fire ground had to run for their lives to a nearby shed as the grass fire flared.

The truck's wheels, plastics and electricals were destroyed. ( Supplied: NSW Police )

The trio had been trying to fight the fire at Tabulam, halfway between Tenterfield and Casino, on Saturday afternoon.

The two men and woman were working to protect two properties on Plains Station Road around 1:00pm, when the blaze suddenly changed direction, hit an area of longer grass and moved quickly towards their truck.

Two of the crew who were on the fire ground took refuge in a shed.

The crew member in the truck activated the crew protection spray, spraying water over the cabin in which he sheltered as the fire passed under him.

Superintendent Chris Wallbridge from the Northern Tablelands NSW Rural Fire Service said the crew had seconds to react.

"It happened very, very quickly with the fire behaviour changing in a matter of seconds and the fire picked up and ran exceptionally quickly to the truck."

"The crew were less than 30 metres from the truck, on the hose and they were unable to get back and had to take refuge in the shed," Superintendent Wallbridge said.

"Yeah very lucky and very thankful to have got out unscathed," he said.

Superintendent Wallbridge said after the crew was assessed physically they jumped into another truck and continued fighting the fire.

The village of Tabulam escaped the fire by a matter of 200 metres when the fire jumped the Clarence River just north of the village centre.

The crew member in the truck activated the crew protection spray, sprayed water over the cabin while he sheltered as the fire passed underneath. ( ABC News: Dave Henderson )

"They were straight back into it and continued to fight the fire for the next few hours until we brought that fire under control," Superintendent Wallbridge said.

All three fire volunteers were experienced fire fighters, with their ages ranging from in their 30s to their 50s.

The RFS's major incident controller for the north region of NSW, Brian Daly said support was being given to the crew.

"The best part about it is that the crew of three are all okay, they're good, we've had counselling sessions with those guys and they are fine," Superintendent Daly said.

The fire truck was extensively damaged with wheels, plastics and electricals destroyed by heat.