Whakaari/White Island tragedy: Paramedic breaks down talking about moment she saw the first victims

The first paramedic on the scene of the Whakaari/White Island disaster has described the moment she came into contact with the first victims as her "worst nightmare" in an emotional interview.

Chrissie Nairn recounted the horror experience for The Eruption: Stories of Survival - a documentary that aired on Three on Monday night telling the never-heard-before stories of those most affected by the tragedy.

She was one of two St John Ambulance staff urgently called to treat burns victims being transported to the mainland by boat on December 9, 2019 - the day 21 people lost their lives after White Island, off the coast of Whakatane, erupted.

But it wasn't until the Coastguard boat she was on pulled up alongside the Phoenix, the boat some of the victims were on, that she understood the scale of what had occurred.

"There was mention of one or two people [injured] - maybe a lower leg injury at that stage. I just assumed that maybe someone had tripped on the rocks," Nairn said.

"My partner Alice and I took our normal kit that we would take to a normal job. We pulled up against the Phoenix, and that was the moment we were faced for the first time with what we were actually dealing with and what had happened.

"It took a long time to register what we were seeing - it was like nothing else. So many people, all covered in mud or ash. There were some horrific burns."

Adding to the trauma of the experience was that the injuries the victims had suffered were so serious, it rendered her normal kit of medications largely redundant.

"They were hard to administer pain relief to because there weren't many places on their body that weren't burnt - we couldn't touch them without hurting them further," Nairn continued.

"The pain relief I carried was just not enough. There were just so many people, and it's your worst nightmare as a paramedic to be overwhelmed or under-resourced, and to not be able to help."

The only two New Zealanders on the island at the time to survive - Kelsey Waghorn and Jake Milbank - also appear in the documentary, telling their story on camera for the first time.

They are among 26 people who suffered injuries during the incident and survived. Both have severe burns and will likely require treatment for the rest of their lives.

The Eruption: Stories of Survival will be available to watch on ThreeNow after the documentary airs at 8:30pm on Monday on Three.