L8 Compliance UK

The UK Health and Safety Executive have produced an Approved Code of Practice which outlines how businesses in the UK are expected to manage Legionella associated risks. This document, commonly known in the industry as L8, provides detailed guidance on specific risks associated with hot & cold water systems and cooling towers as well as general principles for other risk systems. In addition the HSE have produced specific guidance on controlling the risk from spa pools.

This article examines where the Hydrosense range of fast Legionella tests can assist you in meeting your obligations within L8, and therefore allow you to demonstrate compliance with the legislation. Use of the test alone does not discharge all of your legal obligations, and we would highlight the need for duty holders to obtain competent assistance in assessing and managing the risks water systems may pose.

The L8 incorporates an ACOP, along with accompanying guidance on how the requirements of the ACOP may be achieved. These documents are only one way of fulfilling your legal obligations, but most businesses in the UK will aim to follow the general principles described. We have less detailed pages for those outside the UK and those looking for more general guidance on monitoring and control of Legionella.

Paragraph 37 states: It is essential that the effectiveness of the control measures is monitored and decisions made on the frequency and manner of this monitoring.

Paragraph 53(d) states: The scheme should include – checks to be carried our to ensure the efficacy of scheme and the frequency of such tests

Clearly the hydrosense fast Legionella tests could form part of the monitoring scheme. You should determine, and document, the frequency at which you should test using the hydrosense tests. We can provide general guidance on when and where to use the test but cannot provide individual risk assesments.

Paragraph 58(d) states: The scheme should give details on how to use and carry out the various control measures and water treatment regimes including: system control parameters (together with allowable tolerances); physical chemical and biological parameters, together with measurement methods and sampling locations, test frequencies and procedures for maintaining consistency.

You should decide and document where you will take samples from and how often. You should ensure you record all the results from testing.

Paragraph 45 states: Those who are appointed to carry out the control measures and strategies should be suitably informed, instructed and trained and their suitability assessed. They should be properly trained to a standard which ensures that the tasks are carried out in a safe, technically competent manner. Regular refresher training should be given and records of all initial and refresher training need to be maintained. Although training is an essential element of competence, it is not the only factor – it should be viewed as is a product of sufficient training, experience, knowledge and other personal qualities which are needed to undertake a job safely. Competence is dependent on the needs of the situation and the nature of the risks involved.

The instructions for use for the test are self explanatory and may be appended to your procedures. If more detailed instruction or training is required then please get in touch. We can provide specialist training workshops where required.

Paragraph 61.(c) states: If precautions are to remain effective, the condition and performance of the system will need to be monitored. This should be the responsibility of the responsible person or, where appropriate, an external contractor or an independent third party and should involve: monitoring to ensure that the treatment regime continues to control to the required standard.

Paragraph 63 states Testing of water quality is an essential part of the treatment regime, particularly in cooling towers. It may be carried out by a service provider, such as a water treatment company or consultant, or by the operator, provided they have been trained to do so and are properly supervised. The type of tests required will depend on the nature of the system…

System owners can perform the testing themselves, or engage with a specialist water treatment company to undertake testing on their behalf. We are happy to introduce water treatment companies with particular experience using the test. We would normally expect monitoring to include other tests such chlorine level or temperature at the same time, more details are provided within L8 on the other parameters which should be monitorred.

Paragraph 62 states: The frequency and extent of routine monitoring will depend on the operating characteristics of the system, but should be at least weekly.

It is not necessary to undertake a Legionella test every week on every system. However in high risk areas, or when a problem is identified it may be prudent to do so. Clearly in such circumstances a fast test is preferable.

Paragraph 64 states … Periodic sampling and testing for the presence of Legionella bacteria may also be relevant to show that adequate control is being achieved. However, reliably detecting the presence of Legionella bacteria is technically difficult and requires specialist laboratory facilities. The interpretation of results is also difficult; a negative result is no guarantee that Legionella bacteria are not present. Conversely a positive result may not indicate a failure of controls as Legionella are present in almost all natural water sources…

Paragraph 124 states: The monitoring programme should also include the routine sampling and testing for the presence of bacteria, both general (aerobic) bacterial species and Legionella bacteria. Since the detection of Legionella bacteria requires specialist laboratory techniques, routine monitoring for aerobic bacteria is used as an indication of whether microbiological control is being achieved.

The L8 was written prior to the development of the hydrosense Legionella Field Test. Detecting Legionella no longer needs to be technically difficult, or involve laboratory facilities. Whilst it remains the case that a negative hydrosense test result does not provide a guarantee that Legionella bacteria are not present, the relatively high limit of detection means that a positive test result (obtained from a compatible system) almost certainly indicates a failure of control measures somewhere in the system. Legionella Field Test. Detecting Legionella no longer needs to be technically difficult, or involve laboratory facilities. Whilst it remains the case that a negative hydrosense test result does not provide a guarantee that Legionella bacteria are not present, a positive test result almost certainly indicates a failure of control measures somewhere in the system, as detectable levels of antigen are not usually found in incoming water supplies.

The hydrosense test is ideally placed as a rapid first response to any high aerobic bacterial count obtained.

Paragraph 65 states: The results of monitoring and testing should be interpreted by a suitably experienced and competent person and any remedial measures, where necessary, should be carried out promptly.

Interpretation of the hydrosense tests is usually straightforward. A positive test results indicates a problem with the Legionella control regime which requires prompt remedial action. The advantage of the rapid test become apparent here as the action can be taken two weeks sooner than if laboratory results were required.

Paragraph 67 states …records kept [to show the results of any monitoring, inspection or check carried out, and the dates] should be retained for at least 5 years.

As for other tests performed you should keep written or electronic records of the test result, time etc. We do not recommend keeping the test strips themselves as a record of testing as the results have not been validated for long term storage.

Paragraph 112 states …both surface-adhering (sessile) and free-flowing (plaktonic) bacteria need to be controlled for a complete and effective programme.

As well as being able to test for planktonic bacteria with the hydrosense Industrial or Domestic test kits the hydrosense test range includes a biofilm kit for sampling tanks, the inside of pipework or cooling tower pack to detect the presence of Legionella.

Paragraph 119 states Regardless of the results of laboratory testing, to establish an effective biocide programme to control Legionella, it should be remembered that an operating cooling system is subject to unpredictable recontamination both by Legionella and sources of nutrients. Therefore regular microbiological testing needs to be carried out to ensure that the biocide programme remains effective.

Even if you have a periodic lab testing programme in place you should give consideration to using the hydrosense test between those periods to ensure the fastest response to any emerging problem.

Paragraph 130 states: In addition to the routine sampling for aerobic bacteria, the routine monitoring scheme should also include periodic sampling for the presence of Legionella bacteria. This should be undertaken at least quarterly, unless sampling is necessary for other reasons, such as to help identify possible sources of the bacteria during outbreaks of Legionnaires’ disease. More frequent sampling should be carried out when commissioning a system and establishing a treatment programme. Sampling should be carried out on a monthly basis until it can be shown that a system is under control. If a Legionella positive sample is found as a result of routine sampling more frequent samples may be required as part of the review of the system/risk assessment, to help establish when the system is back under control. The sampling method should be in accordance with ISO 11731:1998 and the biocide neutralised where possible. Samples should be taken as near to the heat source as possible. They should be tested by a UKAS accredited laboratory that takes part in the Public Health Laboratory Service Water Microbiology External Quality Assessment Scheme for the isolation of Legionella from water. The laboratory should also apply a minimum theoretical mathematical detection limit of less than, or equal to, 100 Legionella bacteria per litre of sample.

Cooling tower operators should continue to undertake Laboratory testing on at least a quarterly basis (and monthly on systems with poor control) to ensure compliance with this requirement. We would encourage you to test additional sample with the hydrosense test inbetween the periodic lab test (as per Para 119 above) to ensure the fastest response to an emerging problem. You should be aware that since culture tests rely on the detection of viable and culturable organisms and the hydrosense test determines antigen concentration the two measures will not always agree. Where culture results > 100 cfu/L are detected we expect most samples to give positive hydrosense test results, when using e.g. the Industrial Test Kit. If you are concerned about the proficiency of your testing, contact us to discuss how we can assist in demonstrating the competence of your operators and procedures.

Paragraph 131 states Legionella bacteria are commonly found in almost all natural water sources, so sampling of water systems and services may often yield positive results and the interpretation of any results of sampling should be carried out by experienced microbiologists. Failure to detect Legionella bacteria should not lead to the relaxation of control measures and monitoring. Neither should monitoring for the presence of Legionella bacteria in a cooling system be used as a substitute in any way for vigilance with control strategies and those measures identified in the risk assessment.

Positive results are unlikely to be found with the hydrosense test unless Legionella have been growing in your system. However if you require any assistance in interpreting the results we are happy to help.

Paragraph 131 states: Many cooling systems operate on a continuous basis where process conditions preclude total system shutdown except infrequently. Other measures such as side stream filtration, more frequent microbiological monitoring, continuous biocide addition etc, which are reasonable practicable, should be applied and monitored carefully.
bq. similarly Paragraph 138 states: … the packs should be removed at least once a year and preferably every six months. If this is not practicable, it may be necessary to apply supplementary strategies such as side stream filtration, increased monitoring etc…

Hydrosense tests could be used as part of an increased monitoring programme on continuously operated cooling towers. The hydrosense biofilm test can also be used to demonstrate the effectiveness of in-situ cleaning protocols when it is not possible to remove pack every six months for cleaning.

Paragraph 185 states: It is recommended that [Monitoring hot and cold water systems for Legionella] should be carried out: In water systems treated with biocides where storage and distribution temperatures are reduced from those recommended in the section on the use of temperature to control Legionella. This should be carried out on a monthly basis. The frequency of testing should be reviewed after a year and may be reduced when confidence in the efficacy of the biocide regime has been established; In systems where control levels of the treatment regime (e.g. temperature, biocide levels) are not being consistently achieved. As well as carrying out a thorough review of the system and treatment regime, frequent samples, e.g. weekly, should be taken until the system is brought back under control; When an outbreak is suspected or has been identified; Testing for Legionella may also be required in hospital wards with ‘at risk’ patients – eg. Those immunologically compromised.

When control systems are not performing as expected, the hydrosense test is ideal as a rapid response to the emerging risk. Immune compromised partients are particularly at risk, and may be more likely to be infected with species or serogroups of Legionella which represent a lower risk to the general public. They are of course particularly at risk from L. pneumophila sg1 too. In this environment we would combine hydrosense rapid L. pneumophila sg1 tests with traditional laboratory methods.