asked the Secretary of State for Social Services what tests have been conducted by officials of his Department on the chemical Hatacide LP5 regarding its effectiveness in containing legionnaire's disease.
We have not conducted tests on Hatacide LP5 or any other proprietary biocides. The best information available to us indicates that none of the reported outbreaks of legionnaire's disease has been associated with a water cooling system that has received regular conventional treatment using chlorine. In our opinion sufficient statistical evidence has not been published to support the claims of the manufacturers and to justify the substitution of Hatacide LP5 for chlorine in the twice yearly disinfection of cooling towers and evaporative condensers. Where our guidance states that chlorine should be used, we do not consider that biocides are a suitable alternative.