The chief executive of a Dunedin technology company has apologised for the inconvenience caused after busy South Dunedin streets had to be evacuated ahead of the explosion of an unstable chemical.
Smoke was seen rising after the unstable chemical was exploded in Glasgow St, hydrazine monohydrate, just after 9.30am this morning.
The significant response from Fire and Emergency New Zealand (Fenz), police and the Defence Force, was triggered after a staff member at Blis Technologies noticed yesterday afternoon the container holding the volatile chemical had deteriorated.
There were initial indications the situation was not a significant one, but in an unusual development firefighters found out that safely disposing of the chemical meant exploding it.
Parts of South Dunedin were evacuated ahead of the explosion as a 100m exclusion zone was set-up.
A reporter at the cordon heard the explosion, but said it was not that loud.
As of 9.50am emergency services were in the process of reducing the cordon to about 50m and by 12.10pm it was lifted entirely.
By 9.20am it appeared the chemical had been removed from the building and was in place at the car park ahead of the explosion.
In an update to the New Zealand Stock Exchange, Blis said that during a review of chemical stock at Blis Technologies’ research and development laboratory at its South Dunedin manufacturing site "staff noted early deterioration of a container holding a small quantity of a substance used infrequently in basic research".
"Action was taken by staff, in accordance with the company’s protocols, to contact experts to understand the appropriate handling of the chemical and its disposal.
"Fire and Emergency New Zealand has confirmed that the risk mitigation steps and actions were appropriate."
Mr Watson told the Otago Daily Times his staff did all the right things, however the company would investigate whether they could learn from the experience.
"We had it in a specific storage cabinet to manufacturer recommendations, but we'll endeavour to learn from that."
The crystallisation of the substance was noticed by a laboratory manager yesterday who was reviewing the company's chemicals.
"In it's original packaging they noticed some deterioration in the cap area and then rightly undertook some investigation into how to deal with that."
He expected the laboratory to be running again this afternoon.
The destroyed 50ml package was the only hydrazine monohydrate the company carried.
"It's not something we used routinely. It is used at the research level. The substance is definitely not utilised in our probiotics."
He understood the inconvenience to surrounding businesses and would be "going around and apologising".
Fenz Dunedin city station officer Chris Lind said all the processes and systems in place at the laboratory were as it would expect.
"They set a good example in lab cleanliness and management. However, the product is known to degrade over time."
The defence force informed Fenz it was unsafe to undertake the work at night and so arrived this morning.
The substance was in a diluted form, however emergency services called for its destruction by detonation and an 100m cordon to go "to the far end with our preparations for public safety".
Police were earlier advising members of the public of cordons in place at King Edward St, Sullivan Ave, Glasgow St, Carey Ave and Fox St.
Police were assisted with evacuating those people who were inside the cordons as a precaution.
The cordons could be in place until mid morning.
Just before 8.30am Fenz staff were telling people in businesses on Glasgow St to leave and police were evacuating people from parts of King Edward St.
A woman who works in King Edward St said she had been advised to cancel her appointments until at least 10am.
As of 7.15am this morning a bomb disposal van had arrived outside Blis Technologies, where the unstable chemical was discovered yesterday afternoon, and people were setting up hazmat equipment.
There were four fire appliances, a ladder appliance, a hazmat unit and two police cars at the immediate scene and at just before 7.50am firefighters were seen moving sandbags around.
Properties on both sides of King Edward and Glasgow Sts are affected.
Fire and Emergency New Zealand Senior Station Officer Rob Torrance, of Dunedin City Station, said the small volume of hydrazine monohydrate was seen to have crystalised around the lip of its container yesterday afternoon."Once it starts doing that it's quite unstable, if it's moved."
Yesterday firefighters and a hazmat command vehicle rushed to the premises of the oral probiotics company shortly before 3.30pm.
Mr Torrance said the army had informed crews on the ground the chemical was quite stable as long as it was left on the shelf, but it would become hazardous when moved.
An EOD specialist wearing a heavily-armoured bomb disposal suit would go into the building shortly after dawn, gingerly carry the chemical outside, place sandbags around the container then detonate it.
The EOD team would meet police and firefighters at the scene about 7am, but were not prepared to start their work until after dawn.
Mr Torrance said it was among the most unusual situations he had encountered in his long career.
"I've worked in this job for 38 years and I have never heard `disposal method: detonation."'
Unless hydrazine is handled in a solution it is dangerously unstable.
It is used as a foaming agent and is also employed in rocket fuels.
