Colleagues tried to phone victim of ammonia leak in minutes after fatal accident at Northampton Carlsberg factory

Clive Bignall, a contractor working at the factory, was standing metres saw how the cloud sprung from a pipe flange and hit Shropshire man David Chandler "right in the face," killing him almost instantly.

The account was heard yesterday (June 20) on the second day of an inquest into David's death and how the leak was able to happen.

Clive, who was working at the factory under contract with Speedrite International, held back tears as he told the jury how David went behind a heavy piece of machinery he and another man - David Beak - were discussing how to move.

He said: "A cloud of bright blue smoke came straight out this pipe straight into Dave [Chandler's] face.

"I couldn't see the two Daves... I ran out and the floor was evacuated."

Fearing for their the two men's safety, Clive phoned Dave Beak, who had made his way onto the roof. But despite trying dozens of times, he could reach David Chandler.

In the accident on November 9, 2016, over 20 people were hospitalised by the leaking gas.

Now, the inquest has been launched to determine how the leak was able to happen.

Ammonia is used in the industrial process to chill products and brew beer.

But despite checks by contractors Crowley Carbon on two separate valves, a pipe of ammonia suddenly leaked while moving a heavy machine known as a compressor.

Karl Hurst, who represents David's family, said at the inquest: "Somehow that valve became open. And somehow the valve beneath it allowed ammonia to escape from it."

Mr Bignall also told the jury how Speedrite "would not have been anywhere near" the machine if they knew ammonia was in the pipe.

The inquest heard how the pipe had been "isolated" and emptied at least two years before.

The trial continues.