A union leader has called for a new corporate killing charge to be brought in to stop company bosses "getting away with murder".
Two men died in the accident
Tony Woodley of the Transport and General Workers' Union said government plans for a corporate manslaughter offence did not go far enough.
This comes days after union member Michael Alexa was killed when a crane collapsed in south-west London.
The crane driver also died in the accident on Tuesday.
Mr Woodley offered his condolences to the men's families as he addressed the Labour party conference in Manchester.
He said he wanted individuals shown to be at fault to be prosecuted, not just their companies.
"Organisations don't kill people... incompetent, greedy bosses do and they're quite literally getting away with murder," he said.
Mr Alexa, 23, was crushed to death when he was hit by the 165ft (50m) crane as he washed his car.
The crane driver, 37, employed by Norfolk-based Falcon Crane Hire, died when he was thrown from the cab of the machine.
The site has been closed and the Health and Safety Executive is investigating.