The combination of two gases mixed by a West Auckland man before his death would have had a similar effect to lighting a stick of dynamite, an expert says.

The health and safety consultant and former welding tutor, who wanted only to be known as Chris, is also concerned that others could attempt similar risky methods which led to the death of Howard Miller this week.

Miller was killed in a welding explosion on Monday after mixing two compounds, inadvertently creating a "bomb" which obliterated the shed he was working in.

"If he's done it, you can guarantee there are other people out there that are going to be doing it as well," Chris said.


"One thing you don't want to do is give people the inclination it can be done, otherwise, you'll have fools running around making even more of these bloody things."

Chris has almost 48 years' experience in the construction industry and said as sad as Miller's death is, New Zealanders need to learn from his mistakes.

Howard Miller was killed in Monday's explosion in West Auckland.
Howard Miller was killed in Monday's explosion in West Auckland.

Miller was at a friend's house on Universal Drive in Henderson to weld a new exhaust manifold on to his friend's Holden Kingswood.

He had told his friend he had managed to store two components of oxy-fuel - oxygen and acetylene - into a single LPG cylinder.

The two are normally kept in separate bottles, each with a regulator, the two components meet at the welding torch causing the chemical reaction used to cut or weld.

The mixture exploded when Miller ignited his makeshift oxy-fuel welding machine, fatally injuring him and shaking nearby houses and cars.

Chris was astounded Miller had the ability to get both components into the single cylinder.

"What concerns me is A) he had the ability to do this, B) he didn't know what he was doing, and C) the result is he killed himself, and he could have killed others.


"I don't know how the hell he managed to do it. I would equate that this probably [had the power of] half to three-quarters of a stick of dynamite."

Damage at the explosion scene.
Damage at the explosion scene.

All of the products Miller used to create the device were readily at hand and were available for anyone to purchase.

Chris would like to see recommendations into making sure more people knew the risks involved with dangerous gases.

"The message needs to be put out there that these are dangerous things that people are playing with.

"There are inherent dangers out there with these sorts of things, people just aren't aware of them.

"If he's mixed oxy-acetylene into the cylinder that is a massive catastrophe waiting to happen. Especially if he's then decided to weld with the stuff."