legionella control requirements

IMPORTANT CHANGES TO LEGIONELLA CONTROL REQUIREMENTS – HOT & COLD WATER SYSTEMS IN HEALTHCARE PREMISES

The HSE have now published the much anticipated guidance on control of legionella bacteria in hot and cold water systems, HSG274 (part 2).  There have been numerous additions specifically for healthcare premises.

The following changes to your control regime will be necessary to comply with these new requirements.

1. The water distribution temperature has been changed to 55oC (previously 50°C) within one minute.

2. The new guidance states that “TMV strainers and filters should be inspected, cleaned and disinfected annually”.  All TMVs must now be easily accessible, so any boxed in or hidden above ceilings should have provision made for access. Where an annual site disinfection is carried out this will take care of the disinfection requirement.

3. “Healthcare premises must not use flexible hoses that are lined with Ethylene Propylene Diene Monomer (EPDM) as they are known to be prone to bacterial colonisation.” They can only be used on moveable equipment.  The guidance does not give any information as to how we are expected to determine this as it is not possible to tell from a visual inspection.

4. “Expansion vessels should comply with BS 6920 as they often contain diaphragms or bladders made from EPDM.”  They may be marked with the standard they are made to on a label affixed to the item.

5. “Where TMV’s are fitted they must be ‘type 3’ or ‘TMV3’ which are intended for healthcare applications.”  The only 100% sure way to tell is to turn the TMV-fed tap on, then turn off the cold water feed to the TMV – if hot water continues to flow, then this is a ‘type 2’ or TMV2 and it should be replaced.

6. It is now stated that routine “Legionella monitoring should be carried out in healthcare premises.”  The samples should be taken from the calorifier outlet and all sentinel outlets in accordance with BS7592.  There is now specific guidance for healthcare premises which is shown on the following page.  The new guidance does not mention a timescale or frequency for legionella sampling, but as a starting point we would recommend having legionella samples taken twice annually,  with one of these being during the warmer months when bacterial growth may be more likely.

The actions necessary for healthcare premises in response to legionella-positive samples has also been extended and clarified.  The new guidance states the following:

At AKVO we are always available to help with all aspects of water hygiene, including the taking and analysis of legionella samples.

For further information, guidance, or to discuss legionella sampling please get in touch.

Jonathan Beresford BSc (Hons MSc)