A "fit and healthy" marine engineer died from bronchial pneumonia after inhaling fumes from his airbag, an inquest has recorded.

Ron Smith, 59, was involved in a six-car pile-up in November 2010, during which his airbag inflated and was sliced open by a fragment of glass, reports the Northern Echo.

Although unhurt by the accident, Smith told his wife that he thought he had inhaled some of the huge amount of white powder that billowed from the airbag in his Vauxhall Insignia.

ron howard

Ron Smith was driving a Vauxhall Insignia in Hartlepool when he was involved in the six-car shunt

"He said there was so much he couldn't see" his wife June told the Shields Gazette.

She said that though she thought some of the white powder had got into his lungs, she believed his body would "get rid of it by itself."

However the father of two soon began to suffer from coughing and shortness of breath. Less than two months after the accident was taken to hospital and placed on a ventilator in intensive care.

Three weeks after he was admitted, on 31 January 2011, Mr Smith died.

South Tyneside coroner Terence Carney recorded a verdict of "misadventure" on Monday.

He said outside the court that "this man died as a result of this incident [the car crash] and more pointedly because of the explosion of the airbag and exposure to noxious substances."

His wife June told the Northern Echo: “It’s just not fair that you have to lose someone because of something that is meant to save a life.”

However his son added after the verdict: “Ever since it happened we wanted an investigation to see if anybody was to blame and I’m happy with what the coroner has said.”

It is believed to be the first case that a driver has died from inhaling chemicals inside an airbag, although the use of chemicals for the safety devices is well documeted.

Airbags are inflated by a chemical reaction, caused when sodium azide is heated to release nitrogen gas (see Scientific American for a fuller explanation)

Although sodium azide is very toxic, it is mixed with other elements to lessen its harmful effect, meaning that airbags contain a cocktail of chemicals. However this super-fast chemical reaction means that the devices inflate in milliseconds (30 to be precise), rather than being filled with compressed gas which would take much longer.