The recent HTM 01-05 is only the most recent document to re-emphasise that it is a legal requirement for all NHS and private practices in the UK to have a legionella risk assessment. The Risk assessment must cover both the domestic hot and cold water services within the practice as well as the dental unit waterlines and associated water-containing equipment.
Our Risk Assessments for all NHS and private practices is designed to achieve compliance with the relevant Department of Health’s Technical Memorandums.
• Health Technical Memorandum HTM 01-05 – Decontamination in Primary Care Dental Practices
• Health Technical Memorandum HTM 04-01 – The Control of Legionella, Hygiene, “Safe” hot water, cold water and drinking water systems.
The main issue with dental equipment is related to biofilms that can rapidly form on dental unit waterlines. The majority of the organisms in the biofilm are harmless environmental species, however, some dental units may harbour opportunistic respiratory pathogens such as legionella.
Our risk assessments analyse the hazards from biofilm organisms contaminating the dental unit waterlines and the respiratory health risk to both the dental team and patients.
The health risk from the respiratory pathogens including Legionella has been confirmed in all NHS and private practices over the years and to satisfy water regulations and comply with health and safety legislation dentists should institute infection-control measures to maintain the dental unit water at the standard of less than 200 colony-forming units per ml of aerobic bacteria.
Due to the combination of negative publicity, and increased scientific knowledge of dental unit waterlines’ (DUWL) and biofilm formation risk, the contamination of dental unit waterlines has become a prominent infection-control issue.
It is known that Legionella and other opportunistic bacteria can be amplified in the biofilm to reach infection concentrations with the potential for inhalation or direct contamination of surgical wounds for example.
The British Dental Association recommends flushing independent bottled water systems, installing anti-retraction valves on hand-pieces and use of sterile water wherever possible.
However, it should also be highlighted that the requirement to conduct a Legionella risk assessment to cover the domestic hot and cold water services in all NHS and private practices has been around for a long time under HTM 04-01.
The new HTM 01-05 only serve to increase the awareness of the requirement and helps to focus the assessors and practitioners minds on the risks from the equipment and particularly the dental unit water lines.
However, whilst the dental unit water lines are the most obvious routes of exposure for the patient and practitioner, it is also important to confirm that the risk assessment is required to also cover the standard domestic hot and cold facilities within the practice.
This means the domestic hot and cold water taps in tea points, the surgery, decontamination rooms and reception areas. If there are any showers, storage tanks and calorifiers’ in the practice these too will require particular management tasks including cleaning and disinfection on a quarterly basis.