A 31-year-old man was last night still in intensive care at Middlemore Hospital after an explosion at the Affco meat processing plant in Moerewa.
The explosion occurred just before 7.30pm on Thursday in the plant's boiler room, leaving the worker with serious burns from the waist up.
Firefighters from the Kawakawa and Paihia brigades were the first emergency services on the scene.
Read more: One man seriously injured after explosion at Affco's Moerewa freezing works
Kawakawa fire chief Wayne Martin said the volunteers entered the boiler room in breathing apparatus and carried out first aid on the injured man until St John Ambulance staff arrived.
The fire crews put out spots of fire around the boiler room where coal dust had ignited and cooled down the hopper until it was safe to check the coal inside.
It was hard to ascertain at the time whether the explosion had occurred in the coal hopper or elsewhere in the boiler room.
St John Ambulance took the patient to the nearby Bay of Islands Hospital in Kawakawa.
With the Northland Rescue Helicopter tied up with a patient transfer, the Auckland-based Westpac Rescue Helicopter was tasked with flying the injured man directly to Middlemore Hospital in South Auckland.
Intensive care paramedic Casey Drum said the helicopter reached the patient at around 9pm on Thursday night.
He said the man was transported to the National Burn Centre at Middlemore Hospital "because of the severity of his burns". The flight took just under an hour.
Drum said the man had "fairly serious burns to the top half of his body" including his face.
He said the man was in a lot of pain with the burns, but did not suffer any other injuries.
A Middlemore Hospital spokeswoman said the patient's condition had improved yesterday from critical to stable. He was, however, still in the intensive care unit.
A WorkSafe spokeswoman said Worksafe was notified of the incident and had opened an investigation.
Two WorkSafe vehicles could been seen parked in the carpark of the plant yesterday morning.
Also visible on the site were two Fire and Emergency vehicles which were parked outside buildings off to the right of the main entrance.
Two people in hi-vis safety vests were seen entering a nearby building.
There were no signs of smoke or fire damage visible from the road.
A nearby resident said she was out at the time of the explosion on Thursday night, but did not notice any emergency services activity at the plant when she returned home a short time later.
Affco chief financial officer Nigel Stevens did not respond to a request for comment by edition time.
However he was quoted earlier as saying the company was unable to comment until a full investigation had been completed.
"At the moment our main focus is on the wellbeing of our employee and doing everything we can to support his family," Stevens said.
The last emergency at Affco Moerewa occurred in May 2017 when an ammonia leak forced an evacuation of the plant and brought firefighters from as far away as Whangārei.
Emergency services considered evacuating residents at the nearby settlement of Taumatamakuku but drizzly, windy conditions meant the gas dispersed rapidly. No one was injured.