KEY POINTS:
A formal investigation will begin this morning into the coolstore explosion that killed a Hamilton firefighter in the line of duty.
Senior Station Officer Derek Lovell died and seven of his colleagues were injured following the blast, at Icepak Coolstores southeast of the city about 4.30pm on Saturday.
Six firefighters remained in hospital last night, including one who was still fighting for his life.
Smoke smelling of burned cheese was still wafting from the scene yesterday, drifting north over the city.
Motorists heading south from Auckland were driving through the smoke from the Bombay Hills on State Highway 1, as far as 75km from Hamilton.
National Fire Commander Mike Hall told the Herald last night that a formal investigation would begin today.
"The scene has been frozen at this point in time. It's being held for further investigation for the Department of Labour and by Fire Service personnel."
Mr Hall said the inquiry would involve checking the scene for evidence as well as speaking to the injured firemen to work out what had happened.
It was too early to speculate on whether a backdraft occurred or whether the building simply exploded, leaving the firefighters with horrific injuries. Mr Hall said it was also too early to say what type of substance was thought to have been released before the explosion.
Senior Firefighter Cameron Grylls, 29, who had been standing beside Mr Lovell and performed CPR on him at the scene, said two firemen were in the building when it exploded.
The run of events is so far unofficial, but the Waikato region's Assistant Fire Region Commander Roy Breeze said in a press conference yesterday that there had been reports of someone telling firefighters to enter the building despite signs of vapour prior to the explosion.
"What we have heard is that ... someone called out and said, 'Don't worry about it, guys, that's normal', or something along those lines."
But if there was even the slightest chance of danger the men would not have entered the building.
Mr Breeze was also keen to shift the focus on whether Icepak should have had sprinklers in the building.
"A sprinkler system would not have done anything and it would not have saved our firemen," he said.
Firefighters can take up counselling if they want, but Mr Breeze said for now his job was to keep the emotion out and stick to procedural training. The Fire Service was in touch with Mr Lovell's widow, Millie, to ask how it could help with funeral arrangements. It was also working with the families of the other injured men.
Meanwhile, the fire was still burning in small pockets. A 40,000-litre tanker was being refilled by smaller Fire Service tankers, which were doing constant 5km loops back and forth from Riverlea Rd.
Due to the oily and highly flammable cheese remains, firefighters could not simply put water on the fire.
Incident operations manager Acting Rotorua Fire Chief John Booth said: "This is a very, very hard fire to put out. You don't throw water on cooking oils."
Fonterra sent 40 B-train trucks carrying 10,000-litre loads of the cheese and mud "sludge" from firefighting which had been caught in ditches dug to prevent any toxic runoff entering the Waikato River, something which could have poisoned fish and affected drinking water supplies as far away as Auckland.
Icepak's managing director Wayne Garratt said seven staff would be re-employed at three other coolstores. It was not known whether the Tamahere coolstores would be rebuilt.
