Meat processing company Affco has been ordered to pay almost $300,000 after a worker suffered serious burns to almost his entire body.
The worker was tending to the furnace of a boiler at the company's Moerewa plant in July 2018 when the incident happened.
When he opened the boiler door a build-up of coal combusted and sent heat and flames out and into the room.
"The worker was left with severe burns to 75 percent of his body," WorkSafe said in a statement on Wednesday.
"He was placed in an induced coma for five weeks and required multiple surgeries and skin grafts. He has been unable to return to work."
On Tuesday Affco was fined $230,000 and ordered to pay $65,000 for failing to keep the worker safe.
An investigation by WorkSafe found Affco failed to ensure there was an effective system for monitoring and supervising workers overseeing the boiler.
"This failure by Affco to support workers and keep them safe has resulted in life-changing and painful injuries for one of its workers," said Danielle Henry, WorkSafe's acting chief inspector.
"Affco had recorded several instances of excess coal build up which caused these kinds of events and had made unsuccessful moves to rectify this. The business should have had systems in place to ensure workers were aware of the risk and had safe ways of rectifying the situation.
"All businesses, not just Affco, must consider how they can design safe work processes to ensure these incidents don’t occur. This includes ensuring that workers have the knowledge, experience and equipment to do their job safely."
Earlier this month Affco was fined $46,000 after a worker at its Implay plant suffered an acute bacterial infection from an offal spill.