He was one of only two who survived the initial explosion at Pike River, but lost his 21 year old brother Ben in the tragedy that claimed 29 lives.

The news comes as mine rescue staff are entering the Pike River for the first time since the explosion in November.

His father Neville Rockhouse told the The Press that Daniel had to undergo counselling to cope with "sole-survivor syndrome", a type of post-traumatic stress, but was medically fit despite ongoing respiratory problems from the explosions.

"He seems quite happy but he had a few teary moments when underground,” Neville said.

“He's bumped into five or six ex-Pike employees over there and they're good support for him.

"The boy has been to hell and back. In one fell swoop, his group of friends were just wiped out."

On the day of the explosion Daniel started the afternoon shift as the bolter on the ABM 20 bolter miner but reportedly left the face on a loader to refuel it about halfway into the mine.

A white light flashed down the main roadway and the associated blast threw him off the machine and knocked his head into the rock wall.

"I got up and there was thick white smoke everywhere – worse than a fire,” he told the New Zealand Herald.

“I knew straight away that it was carbon monoxide."

He donned his self-contained self-rescuer but reportedly first ran into a dead end of the mine out of panic.

He later collapsed in a main roadway but, after recovering consciousness, managed to get to a compressed air line to gain fresh air according to the report.

Rockhouse reportedly felt “drunk” from carbon monoxide poisoning but managed to not only phone the mine manager but also helped an unresponsive sparky, Russell Smith, make it to a fresh air base in the mine.

Using the compressed air lines in the mine both of them later made the rest of the 1km journey out of the mine.

In a separate report, Smith told the newspaper he was dragged about 300m and he was lucky he arrived at work an hour late or he would have been deeper in the mine.

“It wasn't just a bang,” he told the New Zealand Herald.

“It just kept coming, kept coming, kept coming.”

He reportedly remembered being “pelted with all this debris” and not being able to breathe before Rockhouse helped him about 15 minutes later.

Neville Rockhouse was Pike River Coal's safety and training manager and has been vocal on the need to recover the bodies of the miners despite the technical difficulties of accessing them.

As part of the Pike re-entry, at about 100 metres in, mines rescue staff will install a monitoring point to monitor the mine gases remotely and build a temporary seal, a spokesperson for receivers PriceWaterhouseCoopers said.

There will be two teams of five mines rescue staff involved in this work and they will work in two hour blocks.