Overview
Legionnaires’ disease is a severe pneumonia caused by inhaling legionella bacteria. Although rare, it can be serious, especially in medically vulnerable people.
Although the risk of Legionnaires’ disease associated with dental treatment is considered low, dental unit waterlines (DUWLs) and building water systems can support the growth of microorganisms if they are not properly managed. Because dental equipment routinely generates aerosols, practices must have effective measures in place to control biofilm formation, maintain water quality and comply with legal requirements relating to legionella control.
A responsible person must oversee water safety, and a legionella risk assessment is legally required. Most practices use a specialist water engineer, ideally registered with the Legionella Control Association (LCA), to ensure compliance. The LCA code of conduct for service providers is a useful basis for your contract of work with specialist water engineers. a useful basis for your contract of work with specialist water engineers.
This guidance explains the risks associated with DUWL contamination and outlines the standards expected of dental practices to ensure that water used during patient care remains safe. It describes how microorganisms can colonise water systems, the factors that increase contamination, and the potential implications for patients and staff. The guidance also explains the water quality standards set out in HTM 01-05, including the microbiological limits expected for water used in dental equipment.
The advice also covers the responsibilities of duty-holders and designated responsible persons, including the requirement to undertake a legionella risk assessment, develop a written scheme of control and maintain appropriate records. It explains the role of competent water engineers and how practices can work with external specialists to ensure compliance with health and safety legislation and recognised guidance.
Practical advice is provided on the day-to-day management of DUWLs, and requirements for testing and monitoring, including when microbiological sampling may be required and the role of accredited laboratories.
By following the principles outlined in this guidance, practices can demonstrate effective management of water safety, protect patients and staff, and meet their legal and professional obligations.