A Health and Safety Executive (HSE) Investigation found that employer breaches rather than human error caused a theme park roller coaster crash which left two teenagers needing leg amputations and several other victims with serious injuries.
Merlin Attractions, which owns Alton Towers, has been handed down a £5 million fine for health and safety breaches following the accident which occurred in June 2015.
During the sentencing hearing at Stafford Crown Court, barrister Bernard Thorogood, prosecuting for the Health and Safety Executive (HSE), said the crash equated to "a family car of 1.5 tonnes having collided at about 90mph".
On the day of the accident a test carriage had been sent around the 14-loop ride but had failed.
Engineers then re-set the ride and overrode a computer system "block-stop" which they believed had halted the ride in error, sending a full 16-seater rollercoaster car around the track and into the empty carriage.
Mr Thorogood said that the "fault here is with the employers", not individuals.
He said the engineers were "without guidance from above", and had not been given a system to follow to safely deal with the problem on the track.
"The fault is with the defendant for not devising a scheme, for not guiding the work of the engineers," he said.
The court also heard how there were estimated winds on the day of 45mph. But the manufacturer’s manual said the ride should not be operated at wind speeds above 34 mph.
Since the crash, a number of safety changes have been made by the theme park, including a policy of closing the ride when winds exceed 35mph.
Sentencing, Judge Michael Chambers QC described the crash as a "catastrophic failure".
"This was a needless and avoidable accident in which those who were injured were lucky not to be killed," he said.
Neil Craig, head of the HSE in the Midlands, said Merlin had let its customers down.
"This avoidable incident happened because Merlin failed to put in place systems that allowed their engineers to work safely on the ride while it was running," he said.
"This made it all too easy for a whole series of unchecked mistakes, not just the single push of a button, to result in tragedy."
Lara Murray, a health and safety legal expert with Palmers, said: “This extremely serious incident occurred because safe systems of work were not in place; workers had not been provided with the correct guidance or procedures to follow, which resulted in horrific injuries to members of the public.
“It serves as a reminder for all businesses to review their own risk assessments and employee training manuals to ensure that there are no ‘grey areas’ which might result in a breakdown in understanding, which could, in turn, lead to a serious incident.”
For help and advice on updating your businesses’ risk assessments and employee training manuals, please contact us.