Vine - who has reported from conflict- and disaster-torn countries including Afghanistan, Pakistan and Indonesia and won an award for uncovering the sex offending of Christchurch doctor Morgan Fahey - said that one minute he was sitting opposite a colleague and the next he just disappeared.
"Just 'whoosh', straight down, with absolutely no warning."
The wood pierced Vine's lower back, missing his vital organs, a major artery and his spinal cord by centimetres.
Vine kept the piece of wood, still bloodstained.
"This was no splinter. I'm really lucky it went into the side of the spine and missed everything important."
At first he did not realise the extent of his injury. He stood up, despite a "strange numbing sensation" in his back.
He then felt the area, discovered the wood and was about to rip it out when a colleague stopped him and called an ambulance.
She also called Vine's wife, Parole Board communications manager Sonja de Friez.
Vine then had to wait an "excruciating" 20 minutes for emergency services to arrive.
"It was like being shot by an arrow in a Western. I was waiting for someone to come along with a bottle of whiskey, spill some in the wound and pull it out."
As Vine is 1.89m in height and had to remain lying face down to avoid any further damage, he could not be taken from TVNZ through the lift.
Six firemen hoisted him down in a basket to an ambulance waiting below.
"I'd had four shots of morphine, so I could've been lifted by a winged horse and I wouldn't have known any better," he said.
Later that night, Vine underwent 2 hours of surgery to remove the wood.
He spent two nights in Auckland City Hospital before being sent home to recover - with a drain in place to stop his open wound becoming infected.
Ms de Friez told New Idea she would never forget seeing her husband being wheeled out of surgery, "shaking and ill".
"Even though the stick was out, it was that whole unknown. He looked so incredibly unwell," she said.
"For me, this is incredibly intense. He's very sore and this was a very serious accident. Maybe in six weeks I'll be making deckchair jokes, but not yet."
The Department of Labour is still investigating and TVNZ has removed all wooden chairs from the building.