Falcon Crane Hire has been fined £750,000 after the 2006 collapse of a crane that led to two fatalities.
Crane operator Jonathan Cloke, 37, died after falling from the crane as it collapsed on Thessaly Road in Battersea.
The crane fell onto a member of the public, Michael Alexa, 23, who was also killed.
A subsequent HSE investigation found Falcon Crane Hire Ltd had not investigated a similar incident to the one that caused the collapse just nine weeks before the incident.
Southwark Crown Court heard how sections of the tower crane, which was on a Battersea housing development, separated when 24 bolts failed due to metal fatigue.
The bolts were described as “a significant safety feature on the crane’s slew ring, which connected the mast (tower) to the slew turret”, allowing the jib to rotate through 360 degrees.
When the bolts failed the slew turret and jib separated from the mast and fell to the ground, causing the deaths of the two men.
The HSE found that bolts had failed on the same crane and had to be replaced just nine weeks beforehand.
HSE found the company had an “inadequate system to manage the inspection and maintenance of their fleet of cranes”.
It added the company’s investigation of the cause of components’ failing was also inadequate.
Mr Alexa’s mother, Lilliana, said on behalf of her family: “Michael was a lovely son, a wonderful big brother and a devoted father. His son has had to grow up without the love and support of Michael, who adored him. He was denied that opportunity because his life was taken away and with his, ours too.
“The memories of that day will never leave our family. We heard the crash and felt the ground shake. I found Michael and it’s an image that haunts my nightmares.
“If only we had stopped to chat or parked the car somewhere else he would still be alive. We know we are not to blame but it does not stop us all feeling guilt.
“We cannot comprehend how our beloved son, brother, father and friend who was so full of life has gone. The whole crane industry must learn from our tragedy and the devastation it has caused. We do not want another family to endure the same pain of losing their child.”
A 2012 inquest into Mr Alexa’s death returned a narrative verdict to Westminster Coroner’s Court.
HSE head of operations Mike Wilcock said: “Jonathan and Michael’s deaths were tragic, needless and entirely avoidable.
”These two men need not have died had Falcon Crane Hire taken the right, decisive action when the bolts failed the first time. The company fell far short of its health and safety obligation.”
Falcon Crane Hire Ltd was fined £750,000 and ordered to pay costs of £100,000 for breaching sections 2 and 3 of the Health and Safety at Work Act.