Legionnaires' Disease in refrigeration and associated equipment

Abstract

The paper outlines the nature of Legionnaires' Disease (LD) and its origins. The nature of the bacterium and the four features in the chain of infection are discussed and the essentials of its treatment are outlined. The typical incidence of Legionella Pneumophila in building services is dealt with and UK case histories of outbreaks are used to illustrate the ubiquity of contamination. Susceptible equipment and applications relevant to refrigeration are reviewed and extensive reference is made to Part 1 of the Badenoch Inquiry which, although this referred to hospitals, was very much concerned with refrigeration plant components. The main part of the paper deals with design, operation and maintenance of plant to offer the minimum risk of LD concentrations in carry-over from evaporative cooling equipment, water treatment, including filtration, access, cleaning and drainage arrangements and plant location. The paper concludes that the lessons learned indicate that, while standards seem to be appropriate to minimum risk, more dedication is required to their application. Views expressed in this paper are those of author and do not necessarily represent the policy of the Property Services Agency.