Legionella Management FAQs

No, it’s not a pollutant as a biological pollutant would need to have been created through human influence on the quality of water systems. For example, effluent from farm waste into a river would be a biological pollutant. Legionella is naturally occurring in all water systems, as in it has occurred through evolution and not through man-made influence.

Legionella would not be a pollutant as it occurs naturally in water, however, it can be a hazard in building water systems if not effectively controlled. It would all depend on the frame of reference for the question. The frame of reference would need to consider where the water comes from, what has happened to it, where it is going and most importantly who is asking the question, and why and what they would reasonably expect.

Once the frame of reference is known, they will need to ask if Legionella is a contaminant. This will also depend on the other factors of the frame of reference but the answer is likely to be ‘no’ if Legionella is detected at expected levels. So in river water, it is unlikely that Legionella in very low numbers will be considered a contaminant but in highly purified water for use in a nebuliser, it would likely be considered a contaminant.

If it is a contaminant then it is a special subset of contaminants – a pollutant. A pollutant is something that is likely to have some form of undesirable effect or do some form of harm. Some frames of reference will only look at artificial pollutants, but pollutants can equally be naturally occurring. But again the frame of reference is important when doing this ‘pollutant’ risk assessment – undesired effects or harm to whom or to what (the wider environment, localised plants and animals, a person)?

So if the frame of reference is water from a mains water provider going into a building with Legionella bacteria multiplying in the system to moderate levels and being discharged to a foul sewer, and, if the individual carrying out the risk assessment is the Environment Agency, the answer is most likely no. They expect Legionella to be present in the water and as it is on its way to the treatment plant it is unlikely to have undesirable effects or do harm in this frame of reference.

If the frame of reference is moderate levels of Legionella in water used in a hospital nebuliser by patients with breathing difficulties and the risk assessor is Public Health England, then I believe the answer is likely to be yes. The Legionella bacteria are not expected to be there at these levels, so it is a contaminant. The clear causal link between the contaminant and potential harm to the patients would by definition make it a pollutant within the frame of reference of the patient.

Possibly. You should investigate as to where this detection has originated from and how this has occurred. Are your tenants carrying out the required maintenance tasks on their water services? Do they have an adequate turnover of their outlets and/or showers? To provide the reassurance that your water services will not be affected in the future, non-return valves or water metres can be installed at the point to which the tenants’ water services spur off the landlord’s riser. This will prevent any back-flow into your domestic water services.

Although it is the tenant's responsibility to carry out the required planned preventative maintenance tasks on their water services, such as flushing, landlords’ cannot always be certain that these are being carried out. Installing non-return valves will give you the confidence that any contamination present will not enter the rest of the building’s water services.

Further to this, you, as a landlord, are in a position to request documented evidence from your tenants of the monitoring records carried out on their water services.

Thermostatic mixing valves (TMVs) should only be installed as a preventative to scalding to those susceptible, for example in healthcare premises or for vulnerable individuals. TMVs blend hot and cold water, so there is a potential increased risk of Legionella proliferation as temperatures typically range between 37°C and 46°C in pipework before the valve.

To help manage this risk, TMVs should be sited as close as possible to the point of use and flushed regularly. TMVs should also be inspected on an annual basis as a functionality check, with any strainers cleaned to remove scale, debris, etc. that may be present. A drop test, if applicable, should be carried out also.

It is important to obtain temperatures of both the hot and cold water which supplies the TMVs, to confirm that water is being supplied at the correct temperature. This can be achieved by temperature testing nearby outlets (on the same hot and cold water system), installing test points on the pipework, or alternatively, you can use a touch probe. It must be noted, that correct training should be given when using a touch probe, as there are numerous variables to take into account (e.g. whether the pipework has been painted).

No, unless there is evidence that control measures are not being consistently achieved, it has been recommended in your Legionella risk assessment or it forms part of a more integrated performance review/audit.

A microbiological monitoring regime should be implemented if:

• The control measures for your hot and cold water services, such as temperature or chemical treatment levels, are consistently recorded out of the site-specific parameters. A thorough review of the system and treatment regimes should be carried out, and necessary action should be made. For example, increasing the frequency of testing to provide early warning of loss of control, which could then be reviewed again once control has been regained.

• There is a high risk of host susceptibility of legionellosis within the building e.g. healthcare facilities or care homes.

• There has been a suspected or identified outbreak of legionellosis.

• It has been recommended within your Legionella risk assessment. Your Legionella risk assessment will determine the risk of your domestic water services, and depending on the findings, a recommendation to implement a sampling regime may be made.

Where microbiological monitoring for Legionella is considered appropriate in hot and cold water systems, sampling should be carried out in accordance with BS 7592 Sampling for Legionella organisms in water and related materials. The complexity of the system will need to be taken into account to determine the appropriate number of samples to take and where to take them from.

To ensure the sample is representative of each water system and not just of the water downstream of a fitting or valve, samples should be taken from separate outlets to obtain a true hot or cold water temperature and sample rather than from mixer taps, or thermostatic mixing valves (TMV). Samples should be clearly labelled with their source location and whether they were collected pre-flushing or post-flushing.

It is important to remember that, as part of an integrated performance review/audit a sampling regime for your water services demonstrates a pro-active approach to the management of Legionella risk.

Legionnaires' disease The control of legionella bacteria in water systems, Approved Code of Practice and guidance on regulations (L8) 2013 sets the current requirements for Legionella management including risk assessment.

L8 applies “to the control of Legionella bacteria, in any undertaking involving a work activity managed by you or on your behalf. It applies to premises controlled in connection with a trade, business or other undertakings where water is used or stored; and where there is a means of creating and transmitting water droplets (aerosols) which may be inhaled”.

We offer Legionella risk assessments, accredited through UKAS, together with award-winning management systems, written schemes, training and support. Our own in-house laboratory, our sampling and testing are also UKAS accredited, providing you with complete peace of mind.

Your Legionella risk assessment and management system should be designed to demonstrate your, effective ongoing compliance.

Legionnaires' disease The control of Legionella bacteria in water systems, Approved Code of Practice and guidance on regulations (L8) 2013, sets out clear guidance on when a review of your risk assessment is needed. This states:

“The record of the assessment is a living document that must be reviewed to ensure it remains up-to-date. Arrange to review the assessment regularly and specifically whenever there is a reason to suspect it is no longer valid. An indication of when to review the assessment and what to consider should be recorded. This may result from for example:

(a) changes to the water system or its use;

(b) changes to the use of the building in which the water system is installed;

(c) the availability of new information about risks or control measures;

(d) the results of checks indicating that control measures are no longer effective;

(e) changes to key personnel;

(f) a case of Legionnaires’ disease/legionellosis associated with the system.”

With over 30 years of award-winning experience in supporting organisation in successfully managing Legionella, we can help ensure your management is both realistic and compliant to your needs.

This depends on the nature of the water services you have throughout the building, and where the water is supplied from. As a landlord, you have a duty of care to your tenants within the building, and to provide your tenants with wholesome water in accordance with Water Supply (Water Quality) Regulations 1999. Contract agreements and relationships between tenants and landlords differ across portfolios. Some landlords prefer to take responsibility for all hot and cold water services throughout a building and therefore will be the responsible person for the maintenance of the water services regarding Legionella management. Where tenants add services (i.e. showers), these will typically fall under their responsibility to manage them unless specifically agreed with the landlord to be incorporated into their scheme of management.

If there are cold water storage tanks, under the landlord responsibility, but the outlets are within the tenant demise, it is the landlords’ duty to inspect, maintain and temperature check the stored water. Further to this, the landlord should be carrying out monthly temperature checks of sentinel outlets (nearest and furthest from the water source), as a minimum, to demonstrate that the water is being supplied at recommended temperatures. This should also be carried out if the landlords’ central hot water systems are supplying tenanted areas.

As tenants, it is their responsibility to maintain the water services within their demise as detailed in ‘Legionnaires’ disease - The control of legionella bacteria in the water system, (L8)’. Tenants should have a suitable and sufficient Legionella risk assessment for any water services they have installed in addition to the landlord systems. A written scheme should be implemented on site, detailing all necessary control measures required for effective legionella management.

It is important to note that the general maintenance and cleanliness of the tenants’ systems and outlets can impact on the entire building system, so it is extremely important to ensure that appropriate regimes are in place.