The families of the trapped miners are holding onto hope that their loved ones will emerge alive from the mine.

Lawrie Drew, whose 21-year-old son Zen is one of the 29 trapped in the Pike River coal mine, said he was hoping for a positive outcome.

"We have got faith that they are going to come out... but it's just how long is it going to take to find out for sure what's going on down there," Mr Drew said.

He was speaking after families were briefed this morning on the latest information from the mining company and authorities.

Mr Drew said there was some good information about machinery that had been brought in to assist with the rescue operation and support services for the families had been increased.

There was also an offer to go back to the mine site this afternoon but Mr Drew said he saw no point in doing that.

He said his hope was that the miners are in a "nice pocket" in the mine with enough oxygen to survive.

He said they should have plenty of water and food with them.

"We have just got to be strong for our loved ones and hope they come out. I hope they all walk out."

Asked about how the other families were coping Mr Drew said: "We all want it to [end] on a positive note. But we are all realistic I think too. Some of us cope better than others maybe. Everybody is frustrated, everybody is upset."

Mr Drew said he filled in the hours of best he could. "You have just got to try not to think too much or you break down all the time."

He agreed with Grey District Mayor Tony Kokshoorn that today was "crunch day".

"They have to come to us with some positive information today."