An engineer working at a private healthcare clinic was exposed to toxic gas after the provider fell short of health and safety measures in the workplace.

Anthony Coombes a 59-year-old man from Sandhurst was exposed to the chlorine gas alongside two other workers whilst installing a specialist hydrotherapy pool at the Hampshire Clinic on Basing Road in Basingstoke.

This toxic gas, which is released when sodium bisulphate was added to the pool’s sodium hypochlorite tank can be fatal within minutes and resulted in immediate hospitalisation on March 11 2021.

As an engineer, he was hired by Circle Health Group, the firm that runs The Hampshire Clinic, and asked to reduce the PH levels in the clinic’s hydrotherapy pool. 

However, with no trained employees for the safe operation of pool plant at the clinic’s physiotherapy suite Mr Coombes had not been fully trained in chlorine dosing operations or chemical storage.

After pleading guilty to breaching sections of the health and safety act, the private health group were fined £160,000 and ordered to pay £12,520.03 in court costs on 20 June 2023.

HSE inspector Francesca Arnold said: “Swimming and therapy pool operators must comply with their general duties under the Health and Safety at Work etc Act 1974, which includes making a suitable and sufficient risk assessment of the health and safety risks to their workers and users including the risks of operating pool water treatment systems and the incompatible mixing of chemicals.

“Chlorine derivatives in pools are a well-established method of disinfectant provision and the accidental addition of acid to hypochlorite is the commonest cause of chlorine release incidents in pool buildings, it is fortunate that the injuries suffered were not more serious or even fatal.”

Analysis by HSE’s Science Division following the incident that the maximum volume of chlorine gas was nearly 8000 times over the workplace exposure limit and nearly 400 times over the Immediately Dangerous to Life or Health Limit.