The Department of Labour will not be laying charges over the deaths of two divers in Lake Pupuke on the North Shore of Auckland.
Daniel Stoneham, 33, and Tyrone North, 37, failed to surface from a dive there last July.
They had been diving with other students and an instructor from dive company Helix.
it has carried out after a full investigation, The department says it found there was no breach of health and safety legislation.
The report will be provided to the Coroner's Office for an inquest.