A professional cave diver who has been part of the rescue operation of the football team in Thailand says the dive is one of the most dangerous he’s ever experienced.
Ben Reymenants described the cave network as a labyrinth of small passages and says the dive is one of his top three most dangerous.
“This would be my top three most dangerous dives that I’ve done,” he told 1 NEWS.
“Some of the passages are about 8cm in diameter, you can't go through with conventional scuba gear, you have to take off your gear, push through, dig a little bit and zero visibility, feeling your way until you're past the passage.
“It's 2.5km in so every dive is roughly four hours when you're away from the nearest breathing gap. And that comes after a two-hour climb and wrestle with all the gear.”
“We were looking for a few days for a T junction, which we couldn’t find, there's a lot of dead ends there, it's a big labyrinth, it's 9km long. There was an old French map, 30 years old, that seemed to be quite accurate.”
“There's a British dry cave geologist that told us 'listen, you have to go there, drop down, otherwise you won’t find it, go left.''
Mr Reymenants said he would never have gone so deep unless it was to save people.
“I’m usually called for the bodies, never for live people, to recover from wrecks or caves, 12 kids with their whole lives in front of them, it puts a bit of pressure,” he said.
Because of the difficulty of the dive, medical experts have advised against the 12 schoolboys and their coach diving out.
“When they came back out, they said right, this is a bit beyond these kids’ capacities,” Mr Reymenants said.
"Teaching someone to dive, in tropical shallow waters, that's quite easy but this is pitch black, bad visibility, cave, like I said, small tunnels."
The last thing you want is a panicking diver in a cave, they would not survive that."
For now, Mr Reymenants says the boys are safe, with hope remaining they can be floated out with favourable weather.
“This room, it stays dry the entire monsoon, so fortunately safe, but yes how safe can you keep a kid in a dark room for three months?”
“If the water drops another two metres they can probably float them out with life jackets and there's only one or two places they’d have to make a little dip dive or, the kids actually claim they heard birds and chickens nearby.”
Mr Reymenants says the operation is huge, with 5000 people on site and teams working to lay cables down to the team.
“We're not allowed to film inside but it's a huge operation, there are American, Australian teams,” he said.
“They started laying telephone and electricity cables to have some contact and lights, something they started doing before the major floods, so they’re already two-thirds of the way with that cable.”