One of the world’s foremost water safety experts is using the Royal Free Hospital as a global example of a building with a safe water system following an inspection.

Dr Susanne Surman-Lee, one the world’s lead investigators into water contamination, toured the hospital in Pond Street, Hampstead, in November 2012, to check up on its filtration system.

In hospitals cleanliness of water and hygienic disposal is paramount given the circulation of germs.

The inspector, who used to be head of the Health Protection Association, said the Royal Free’s water system should serve as an example to other hospitals, commending the hospital’s efforts to reduce the risk of bacteria getting into the system.