Legionnaires' disease is wholly preventable and there are no reasons why anyone should contract it. There are a variety of statute laws, The Health & Safety at Work Act 1974, statutory instruments, and codes of practice that require those responsible for buildings to assess any risks present and act upon them. Failure to react to a risk and / or exposure to public / personnel is the offence.
The Control of Legionella Bacteria in Water Systems Approved Code of Practice & Guidance applies to the control of legionella bacteria in any undertaking involving a work activity. Also, to premises controlled in connection with a trade, business or other undertaking where water is used or stored and where means of creating and transmitting water droplets which may be inhaled, thereby causing a reasonably foreseeable risk of exposure to legionella bacteria.
Legionellosis is the generic term given to diseases caused by the bacterium Legionella spp and owners and operators of buildings need to ensure that all of their buildings they own and operate comply with the above ACOP. If they do not they could be prosecuted under the Health & Safety at Work etc. Act 1974.