WorkSafe will not be laying charges following an investigation into allegations of unsafe handling of asbestos in buildings damaged in the Canterbury earthquakes, it says.
The agency launched the investigation earlier this year over claims the Earthquake Commission and Fletcher Earthquake Repairs' risk management systems were inadequate during the early stages of the rebuild.
WorkSafe chief executive Gordon MacDonald said the investigation found deficiencies at the start of the Home Repair Programme but the risk to workers and residents was low and prosecution would not be justified.
Mr MacDonald said the hazards could not be quantified but gave an assurance there was nothing to suggest people were in any great danger.
He admitted there were failings in the early stages through to at least 2011 but said he could not give any figures about the size of the problem.
"I don't have precise information that will give me the confidence to be able to give you a number at this stage but what I can say is that it was not in all cases that such testing, which should have been done, was undertaken in those early days," he told Checkpoint.
Inspections and testing had found there was no high risk of exposure, Mr MacDonald said.
"Fletchers themselves have undertaken some airborne asbestos sampling of work that was typically done during the refurbishment exercise and we've done some testing of a limited number of houses ourselves.
"Our conclusion from that work is that the actual risks of exposure were low."
But Mr MacDonald's assurances did not satisfy Christchurch plumber Daniel Moore, who said he was leaving the South Island city as soon as he could see house as he did not want to work in buildings which had asbestos without his knowledge.
Listen to more
Mr Moore said after having his family exposed to the material during repairs to their home, he no longer had faith in the system in Christchurch.
"I don't want to be working in these houses ... so I'm moving right down south to a small, little town," he said.
Christchurch homeowner Linda Boyce told Checkpoint she intended to take a private prosecution against the Earthquake Commission over asbestos contamination in her house.
She said the asbestos came from a stipple ceiling which Fletchers removed part of, and that she asked for it to be tested for a long time.
"Four months after we moved back into the house, they finally did an air test and that air test was, in my mind, unsatisfactory."
Ms Boyce said she had been living for more than two years in a house which contained asbestos.