Legionella Management

Accredited, successful, and award-winning are just three facts you could use to describe over 30 years of helping organisations achieve compliance and peace of mind in Legionella management.

Legionella Advice

UKAS accredited to ISO 17020 and Assured Advice through a Primary Authority Co-ordinated partnership with the City of London Corporation for our Legionella risk assessments, our market-leading management support combines specialist building services knowledge, together with our own UKAS accredited in-house laboratory, which means we have total control of the process from risk assessment and sampling strategy to presenting our findings to you. This helps factor in accuracy and reliability and factor out error. 

From 1st October 2017, we will also be offering our Legionella risk assessments as Assured Advice through a Primary Authority Co-ordinated partnership with the City of London Corporation. The advice covers “the competence and ability of Assurity Consulting to undertake suitable and sufficient Legionella risk assessments in accordance with the relevant legal requirements.” 

Legionella bacteria is one of those premises issues that can have a dramatic impact on people and the organisation in a very short space of time. You must be sure your Legionella risk assessment, scheme of management, training, and feedback processes are robust and effective. You have to be able to identify the long-term trends, not just the short-term changes. When you can contract out the tasks, but not the responsibility, you have to be able to fully trust what you have in place.


  • Strategic-level Legionella management reviews
  • Legionella risk assessments UKAS accredited to ISO 17020
  • Legionella risk assessment reviews
  • Water management documentation (policy and procedure)
  • Water quality assessments
  • RoSPA Assured Legionella awareness training
  • Legionella management training
  • Bespoke Legionella training based on your requirements
  • Legionella testing 
  • Legionella sampling 

If you need expert, independent advice on your Legionella management, please call us today for a detailed, confidential and without-obligation discussion of your requirements.

Click here to view our independent guide to Legionella

What is Legionnaires' disease?

Legionnaires’ disease is a form of pneumonia, fatal in approximately 12% of cases. The bacterium Legionellapneumophila serogroup 1 is the most common cause of Legionnaires’ disease. It first hit the headlines in 1976 after an outbreak among attendees at an American Legion Convention in Philadelphia, where 221 people were infected, of which 34 died.

Legionnaires’ disease primarily affects people who have increased susceptibility due to predisposing factors, such as age (50 years +), smoking, existing illnesses etc. Men are also three times more susceptible than women. Legionella bacteria infections can only be contracted by the deep inhalation of tiny water droplets, called aerosols, which are contaminated with legionella bacteria. Aerosols can be produced from water systems that create sprays, such as showers, cooling towers, spray taps, decorative fountains and Jacuzzis. Infection by person-to-person contact has not been reported.

Legionella bacteria can pose a real threat to your buildings and the people who work in them. 

Read our independent workplace guide on Legionella


Professional assessment

Professional assessment

Our management team, including chemists and microbiologists, leads from the front on Legionella management, ensuring the up-to-date excellence of our consultants’ advice.

Accredited service

Accredited service

We have combined UKAS accreditations for Legionella risk assessment to BS 8580:2010 with water sampling and testing for Legionella. These combined standards mean we can offer you more practical evidence of management control, minimising business and reputational risks.

Independent advice

Independent advice

The fact that our consultants do not offer remedial services gives them the freedom to focus totally on your situation and your needs, now and into the future. 

Peace of mind

Peace of mind

Only with expertise such as ours in your corner can you rest easy, secure in the knowledge of your safety from Legionella.

Legionella management FAQs

    Is Legionella bacteria classed as a pollutant in the UK?

    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.

    My tenants have detected Legionella bacteria. Will this affect my system, as a landlord?

    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.

    Related services: Legionella Management
    What are the maintenance tasks needed for thermostatic mixing valves (TMV) in regards to Legionella?

    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).

    Related services: Legionella Management
    Is it a legal requirement to sample for Legionella from my hot and cold water services?

    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.

    Related services: Legionella Management
    What is the requirement for Legionella risk assessments?

    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.

    Related services: Legionella Management
    When do I need to review my Legionella risk assessment?

    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.

    Independent Legionella Management
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    As a landlord, with tenanted floors, are temperature checks of the water services necessary?

    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.

    Related services: Legionella Management
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Legionella Management and Risk Assessment

If you would like expert, independent advice on legionella management within your building, please contact us for a detailed, confidential and without-obligation discussion of your requirements.

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Customer testimonials

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"Assurity Consulting continue to provide Unibail-Rodamco-Westfield with excellent support and guidance in relation to Legionella and air quality risk. They provide cost effective solutions ensuring that the interests of our business are always met. Their employees are always pleasant and knowledgeable, and they consistently deliver clear and concise reports, which are easy to understand and action."

- Jakub Skwarlo, Director of Operations UK, Unibail-Rodamco-Westfield

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"We carry out assessments every year and Assurity Consulting provide us with very detailed information about the condition and output of our plant/systems. They also serve as an independent review of the planned preventative maintenance work carried out by our building services contractors."

- Richard Comfort, Head of Facilities, esure

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"Having worked with Assurity Consulting for a number of years I know I can rely on their support and professional advice on all aspects of workplace compliance including areas that are not specifically detailed in our agreement. Having an independent view point is essential and their online compliance management tool enables central monitoring to be carried out with ease."

- Carol Morrison, Compliance & Supplier Relationship Manager UK&I Properties, Fujitsu Services Ltd

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