Westminster Magistrates Court heard how LSDM had been in the process of redeveloping a warehouse in Wembley.

When four workers tried to move a ventilation unit into position, the working platform became overloaded and gave way.

Neither the work at height nor the lifting operations were planned properly.

Two of the four injured men suffered leg fractures, while a broken collar bone were among the other injuries caused by the incident.

An HSE investigation found the company failed to manage the risks when working at height and carrying out the lifting operation.

The company also failed to have the right level of trained personnel and supervision in place to carry out these tasks safely and effectively.

LSDM of Fourth Way, Wembley pleaded guilty to safety breaches and was fined £450,000 and ordered to pay costs of £1038.

Speaking after the hearing HSE inspector Jack Wilby said: “The safety failings by this company are severe and it is lucky that the injuries were not more severe.

“This incident highlights the importance of planning work, in this case both for lifting operations and working from height, to ensure it is carried out safely.”