White Island eruption survivor Jesse Langford has revealed the heartbreaking agony of leaving his family behind as he walked off the volcano in his desperate bid for safety.

The 22-year-old Australian, who lost his parents and sister in the blast, was one of 47 people on White Island, also known as Whakaari, when it erupted in December 2019.

The Sydneysider was one of the few at the crater’s rim during the blast to survive.

After three years, Langford has documented his ordeal for the first time in a new Netflix film, The Volcano, including the minutes after the eruption.

“Up near the acid lake, I was just sitting there rocking, rocking in pain. Everything, my whole body, was just tingling,” he says in the film.

“My arm’s covered in grey ash. I was just thinking ‘I’m gonna die here. I’m gonna die. That’s gonna be it.’

“I was sat in the middle of about half a dozen or more people, people who are dead or dying, and in that time you could hear their voices slowly start to dissipate – the screaming becoming less frequent, the crying becoming more quiet.

“After sitting there for half an hour I came to the realisation that no one was coming. Then something clicked, just to get up and go.

“Standing up and walking away from our parents. That was I would say the toughest thing I’ve ever had to do.”

With burns to 90 per cent of his body, Mr Langford staggered about 300 metres to the water’s edge where he boarded a tour boat to safety.

After initial treatment in New Zealand, he was flown to Sydney, where he remained in a coma for more than a week.

When he woke on December 17, his grandfather was left with the unimaginable duty of telling Mr Langford his father Anthony, his mother Kristine and his sister Winona had all died.

On December 30, Mr Langford sat in Royal North Shore Hospital, watching a live stream of their joint funeral.

Amid the devastation, the film also details Mr Langford’s physical and mental recovery.

Told he might be in hospital for two years, the teenager defied expectations to be discharged after two months.

“I’m a stubborn bastard,” Mr Langford said.

Rory Kennedy, the prolific and award-winning director who made the film, said the interview with Mr Langford was one of the most moving experiences of her career.

“I’ve been making documentaries for 25 years now and have covered a range of subjects from [Iraq prison complex] Abu Ghraib to human rights abuses to AIDS,” she said.

“That interview was one of the most intense I’ve ever done.

“To understand what he went through, losing his family and finding whatever it was in himself to be able to get up and walk to the ocean’s edge to find help, it’s inspiration at its core. He’s a beautiful human.”

The documentary also includes never-before-seen footage from the island on the day of the eruption, including the blast and the moment the tour group was ordered to run.

“In some cases, we’ve pulled back a bit just because of the intensity of the footage and the rawness,” Kennedy said.

Kennedy uses the first-person storytelling of Mr Langford, other survivors such as American honeymooners Matt and Lauren Urey, tour guide Kelsey Waghorn, helicopter pilots and Whakatane locals.

The blast killed 22 people including 14 Australians.

• The Volcano screens on Netflix from December 16.

-AAP