The HVCA warning on hot water systems (http://www.plantengineer.org.uk/article/37779/Hot-water-warning-from-heating-and-ventilating-contractors-.aspx), while technically correct, is off the mark from a health standpoint.
That is the view of Aquatech's Frank Rosa, "FRANK ROSA, author of 'Legionnaires disease, prevention 'and control'.
Responding to the story on Plant Engineer dated 28 October 2011, Rosa says: "If a person is unable to feel pain from high heat, yes that person is at risk. However, the entire population is at risk to Legionnaires disease when conditions are ripe for its amplification and aerosolisation, such as showering."
Rosa worries about the justice of Midland Heart housing association' fine, "for doing the right thing".
"Thousands die from Legionnaires disease. If the installation of TMVs [thermostatic mixing valves] was too expensive, perhaps someone should have suggested temperature. shut-off valves. These will pinch off the flow of water, if the mixed temperature increases above its set point."
