New Zealand's workplace safety watchdog has charged 13 parties following a major probe into the volcanic eruption of Whakaari last year that killed 22 people.
The blast, which claimed 14 Australian lives, occurred during a bright summer day while tours to White Island were taking place, despite a heightened risk of eruption.
"This deeply tragic event was unexpected. That does not mean it was unforeseeable," WorkSafe NZ chief executive Phil Parkes said.
"The victims, both workers and visitors alike, all had a reasonable expectation that they could go to the island knowing that those organisations involved had done all they were required to do to look after their health and safety."
Ten organisations have been charged with breaches under the Health and Safety at Work Act, and could face fines of up to $NZ1.5 million ($A1.4 million).
A further three individuals have been charged as directors or individuals who failed to meet health and safety obligations.
The parties have not been named as under NZ law, they have the right to seek name suppression on their first court appearance on 15 December.
Volcanic Air director Tim Barrow told the Rotorua Daily Post it was one of the organisations charged.
"There's not really too much I can say. I can confirm we are one of the parties that has been charged but we don't know what the exact process is," Mr Barrow said.
Families of victims of the White Island eruption embrace after arriving back to the Whakatane wharf following a blessing at sea. Source: AAP
The probe is looking only at organisations involved in the tourism aspect.
New Zealand Police is conducting an investigation on behalf of the coroner.
An Australian legal action is also being brought against Royal Caribbean, the company which operated the Ovation of the Seas cruise ship, which offered the tour to its guests.
Two tour guides for White Island Tours also died following the eruption.
Last week, Horst Westenfelder became the latest casualty from the blast, dying in an overseas hospital as a result of complications from surgery.
The eruption took place during a spell of heightened 'level two' volcanic unrest, as measured by NZ's official seismic monitoring agency.
No tourism has occurred on the offshore volcano, found 50km north of Whakatane on the north-east of New Zealand's North Island, since the tragedy.
