Disinfection of Water Systems in Accordance with Eu Directives on Health and Safety in Working Environments: Use of A Technologically Advanced ClO2 Generator

Abstract

It is currently of great interest to develop prevention systems for the management of the risk of microbial contamination of water in buildings of various types in which work is done. In this regard, international organizations have drawn up reference guidelines and in the EU countries specific legislative provisions indicated in the EU directives must be observed. A pilot system, copying a building pipeline, was designed, and developed to test water treatments with a ClO 2 generator. Chemical and physical parameters were monitored in real time and the effectiveness of disinfection was tested on several microorganisms, focusing on Legionella. The scale plant reached steady state within 24 hours and maintained equilibrium, showing stability to chemical and physical parameters. Simulations showed disinfection efficacy for different contaminations (>1,000,000 CFU) under water system conditions. Escherichia coli counts and other indicators showed a 99.999% reduction within 15 minutes while Legionella and other environmental species showed a 99.999% reduction within 30 minutes. In addition, the system proved to be effective on complex microflora and other species and allowed to demonstrate adherence to the regulatory framework and legislative requirements (italian legislation's accepte of EU directives on health and safety at work D.lgs. [1]. And with particular reference to the European Directive [2] and European Parliament's Directive [3].The study model can be easily extended to simulate particular risk situations, verifying for each of them the effective compliance with current legislation. This pilot model can be a feasible support in validating or comparing alternative solutions and new technologies for disinfection of water.