But when he was seconded from his usual environment department role to help during the devastating January bushfires he did because that's the sort of practical, positive colleague he was.

His death in a head-on crash returning to base on January 3, has had a profound effect on the 43-year-old father of two's family, friends and colleagues.

Novak John Selby, 47, has spent six months behind bars already awaiting sentence for his dangerous driving causing Mr Kavanagh's death, after crossing entirely onto the wrong side of the Goulburn Highway on January 3.

He's expected to learn in the next two weeks how much longer he'll be there.

Mr Kavanagh was a passenger in the Department of Environment, Land, Water and Planning ute driven by fellow firefighter John Martin.

They were heading back to their base at Alexandra after putting out campfires and advising campers to leave, ahead of what was expected to be a severe fire day the following day.

A state of disaster had been declared in Victoria and there was a light smoke haze in the area.

Selby had left a local trout farm after looking for work. Instead of following the curve of a sweeping bend on the Goulburn Highway, he continued straight and crossed double lines onto the wrong side of the road.

Mr Martin said he and Mr Kavanagh saw Selby's ute coming at them head on, so far on the wrong side of the road he was almost in the dirt.

He tried to take evasive action but the cars collided. Mr Kavanagh was pulled from the wreckage but could not be saved.

Prosecutor Robyn Harper told the County Court on Tuesday that Selby claimed at the scene and to police days later that the DELWP car was on the wrong side of the road, not him.

Mr Kavanagh's wife Jude said they'd spent the night before laughing at their two young children playing under the sprinklers.

"He captivated people with his storytelling and had a sparkle in his eyes ... his zest for life was infectious," she said.

His parents added that Mr Kavanagh's experience fighting the Black Saturday bushfires and later fires in Harrietville and NSW had a profound and changing effect on him.

"All emergency personnel do a wonderful job in difficult and dangerous circumstances. We should all be eternally grateful for their sacrifices," they said.

Three other firefighters were killed fighting blazes in Victoria in January.

Selby's lawyer said he had written a letter of apology to the Kavanagh family, and was remorseful for his actions.

He accepts Selby must be jailed. He'll be sentenced at a later date.

Australian Associated Press