Almost a year and a half after Whakaari/White Island erupted, a court hearing will get underway on Thursday in Whakatane, the town closest to the disaster.
The volcano erupted in December 2019, killing 22 people who were among a group of 47 on the island.
A two-day hearing of WorkSafe's prosecution will start on Thursday at the Whakatane District Court and is expected to attract massive interest within the community.
A second venue has been set up to livestream the proceedings for the public and media.
WorkSafe alleges 13 parties - 10 organisations and three people - failed in their duty of care to visitors to the island.
The tourist companies facing charges are Whakaari Management Ltd, Volcanic Air Safaris Ltd, White Island Tours Ltd, Kahu New Zealand Ltd, Aerius Ltd, ID Tours Ltd, Tauranga Tourism Services Ltd, and Inflite Charters Ltd.
Also facing charges are government agencies GNS and the National Emergency Management Agency.
The three individuals are James, Peter, and Andrew Buttle. The Buttle family owns the island and all three men are directors of Whakaari Management Ltd.
Under the WorkSafe charges, each organisation faces a maximum fine of $1.5 million and the individuals could be charged $300,000.
Earlier, WorkSafe chief executive Phil Parkes said the charges conclude the most extensive and complex investigation ever undertaken by the health and safety regulator.
The charges are centered on the everyday operations of the parties and do not relate to the rescue and recovery of victims after the eruption.
The hearing is administrative but matters likely to be discussed include whether a future trial should be held in Whakatane.
Parties could also be asked to enter pleas.
