An ecological survey firm has been fined £12,000 after a worker broke her back after falling four metres at the former Severalls Hospital in Colchester.

DF Clark Bionomique Ltd, based in Burnham Road, Althorne, was searching for wildlife at the disused psychiatric hospital ahead of the site being sold for redevelopment.

The 34-year-old surveyor, who has asked not to be named, fell through a loft hatch onto a concrete floor on May 12 last year.

She suffered a fractured vertebra at the base of her back and was in Colchester General Hospital for seven days.

On her release she needed to wear a back brace for three months to prevent bending or twisting between her neck and waist and was unable to work for several weeks.

DF Clark Bionomique pleaded guilty to breaching two health and safety regulations during a hearing at Chelmsford Magistrates’ Court today after a Health and Safety Executive (HSE) prosecution.

The court heard that though the company was aware the hospital buildings had not been used or maintained since the site closed in 1997, the safety assessment was too general and failed to identify the risks of falling through as the roof was likely to be fragile with rotting timberwork in the disused loft spaces.

Magistrates fined the firm £12,000 and ordered it to pay costs of £1,138.50.

After the case HSE inspector Edward Crick said: “The failure of DF Clark Bionomique to properly plan this wildlife survey has resulted in a significant injury to one of its employees.

“This is a company which undertakes surveys in locations ranging from a tree, to something considerably more complex such as the one being undertaken at the old Severalls hospital site.

“A ‘one size fits all’ approach is obviously not suitable and the company’s tick-box approach to risk assessment failed to protect this worker.

“Falling through fragile surfaces is a well-known risk, particularly in the construction industry, and any work at height needs to be properly assessed and managed, including sometimes seeing if the work needed can be done in a way that avoids any work at height at all.”