One of the students involved in Wednesday's rock-climbing accident says he didn't think he was going to survive.

Spotswood College student and New Plymouth local Campbell Shaw says "pure panic" set in during the ordeal.

"I just didn't think I was going to survive myself," he told TV ONE's Close Up.

Campbell was one of eleven Year 13 students from the Taranaki Outdoor Pursuit Education Centre (TOPEC) doing a rock-climbing exercise at Paritutu Rock off the coast of New Plymouth.

He told Close Up the students were excited about the trip, although climbing Paritutu Rock was not part of the original plan.

"We weren't supposed to be going to the rock, we were supposed to be going somewhere else but the decision was to go there.

"It was a fine day, but as soon as we got there the clouds came over and it was raining," he said.

"I think everyone was excited about it, everyone just thought it was a harmless climb, we're all safe, we've got harnesses.

"When I looked at everyone on the rock they were in the same boat I was...but at a certain point we got to, the waves just became too big."

Campbell says the three students who fell into the water were on a flat area of the rock, somewhere they were not likely to lose their footing.

He said at that point they weren't harnessed in.

Campbell says when the instructors realised what had happened, they did all they could to protect them.

Instructor Bryce John Jourdain unclipped himself and dived into the sea.

"As soon as he heard that two students were in the water he just instantly dove in there and did all he could."

Spotswood College Head Boy Casey Davies-Hall told Close Up that Jourdain didn't fall into the sea.

"He took away his clip and dived in after them. He did everything he could in the situation.

"It's just a freak accident and we don't hold any blame," he says.

Jourdain, along with students Stephen Lewis Kahukaka-Gedye and Joao Felipe Martins De Melo, both 17, are still missing.

The third student managed to cling onto a rock and was winched to safety.

Campbell says if he has learnt anything from the past few days, it is to live life.

"Live life as much as you can because you never know when something like this is going to happen."

The search for the missing trio is being scaled down but will continue tomorrow.