Stray spark likely cause of explosion

00:55, Jan 28 2014
Gas bottle explosion
Images from a gas bottle explosion in Clyde St, Invercargill on Monday, January 27, 2014.
Gas bottle explosion
Images from a gas bottle explosion in Clyde St, Invercargill on Monday, January 27, 2014.
Gas bottle explosion
Images from a gas bottle explosion in Clyde St, Invercargill on Monday, January 27, 2014.
Gas bottle explosion
Images from a gas bottle explosion in Clyde St, Invercargill on Monday, January 27, 2014.
Gas bottle explosion
Firefighters are at the scene of a gas bottle explosion in Invercargill on Monday, January 27, 2014.

An explosion that left one man seriously injured yesterday may have been caused by a stray spark.

The man remains in a serious condition with head and abdominal injuries. The Southland Times understands Dave Evans was the man injured when a gas cylinder exploded outside Southern Brakes and Driveline in Clyde St about 3pm yesterday. 

A hospital spokeswoman said Mr Evans was in an induced coma with serious head and abdominal injuries. He was one of two people injured in the explosion.

Meanwhile, Fire Service acting assistant area commander Neil Ladbrook said it was believed a leaking single acetylene gas cylinder was ignited by a spark that came from the ute.

"It appears when a door was opened to the utility some sort of spark either mechanical or electrical was let off," Mr Ladbrook said.

When the ignition source came into contact with the acetylene gas it caused an explosion that was felt at the fire station in Jed St, he said.


The Australia New Zealand Industrial Gas Association website says acetylene is very easy to ignite. In fact, a static spark is sufficient to ignite acetylene. The static charge developed by walking across a carpet floor on a dry day can be 1000 times greater than that needed to ignite acetylene a safety sheet on acetylene says.

Acetylene is the most common gas used for fueling cutting torches in both general industry and the mining industry. 

Worksafe New Zealand were investigating the cause of the explosion, which was felt across the city.

Southern Brakes and Driveline owner Luke Nicol said the man injured in the explosion had been inside his shop before heading back out to his Downer ute.

The man had not brought a gas cylinder into the shop but when he returned to his truck there was a massive explosion, Mr Nicol said.

The blast shattered the business' windows and when he went outside he saw a gas bottle lying near the wreckage of the Downer ute, Mr Nicol said.

The business was up and running and the smashed windows had been replaced. 

Yesterday, ambulance communications team leader Paul Burns said a man in his 40s was taken to Southland Hospital with serious head injuries. A second person was understood to have been treated at the scene, he said.

A Downer ute and a second ute were both damaged. The tray of the Downer ute was blown to pieces.

Broken glass littered the area, with the windows from Southern Brakes and Driveline, and Ramset New Zealand blown out.

Emergency services raced to the scene, and the surrounding area was evacuated and cordoned off.

Workers from adjacent businesses and others several hundred metres from the scene of the explosion described the noise as "like a bomb going off".

Southern Bolts and Fasteners owner Elvin Knowler, whose shop is only a few doors from where the gas bottle exploded, said the blast shook his shop.

When he raced outside he saw a man lying on the ground.

"He was moving his hands and his eyes were open but he looked in a pretty bad way," Mr Knowler said.

"I saw the debris flying everywhere from my shop."

Precision Panel and Paint staff also saw a man lying on the ground after a "horrendous" bang shook their building.

Southland Glass Service glazier James McLennan said he was cutting glass when the massive explosion shook the building.

"It was lucky all the glass didn't come down," he said.

Invercargill station officer Colin Russell said when fire crews arrived they found a large amount of debris and one person injured and being helped by members of the public.

After the injured person was taken to hospital and the area had been evacuated and cordoned off, fire crews worked with a BOC gas representative to remove the cylinder from the scene, he said.

The explosion is being investigated by WorkSafe New Zealand.

Downer representatives in Invercargill did not want to comment at this stage.

The explosion also caused problems with calls from the Telecom network.

Telecom head of public affairs Conor Roberts said there was a temporary overload on the network after the explosion, as everyone in the Invercargill CBD called each other to find out what was going on.

The Southland Times