What Is Legionella?
Legionella bacteria is commonly found in water. The bacteria multiply where water temperatures are between 20-50°C .The bacteria are dormant below 20°C and do not survive above 60°C.
Legionnaires’ disease is a potentially fatal type of pneumonia, contracted by inhaling airborne water droplets containing viable Legionella bacteria. Such droplets can be created, for example, by: hot and cold water outlets; atomisers; wet air conditioning plant; and whirlpool or hydrotherapy baths, and pose a threat to public health. We test for legionella bacteria in water systems following an approved code of practice, helping you control the risk.
What you need to do
Every premises that falls under the Health and Safety Act 1974 must have a suitable and sufficient Legionella Risk Assessment . When the risk assessment is complete you should have a "Written Scheme of Control” so that you can effectively manage legionella proliferation and dissemination on your sites. This could include;
The legislation tells us;
To comply with their legal duties, duty holders should:
(a) identify and assess sources of risk of legionella exposure and growth. This includes checking whether conditions will encourage bacteria to multiply, taking steps to control legionella levels and prevent legionella growth. For example, if the water temperature is between 20–45 °C, if there is a means of creating and disseminating breathable droplets, such as the aerosol created, eg by water cooling towers, showers and spa pools; and if there are ‘at risk’ susceptible people who maybe exposed to the contaminated aerosols
(b) if appropriate, prepare a written scheme for preventing or controlling the risk
(c) implement, manage and monitor precautions – if control measures are to remain effective, regular monitoring of the water systems and control measures is essential. Routine monitoring of general bacterial numbers can indicate whether you are achieving microbiological control and sampling for legionella is another means of checking that a system is under control
(d) keep records of the precautions
(e) appoint a competent person with sufficient authority and knowledge of the installation to help take the measures needed to comply with the law, and ensure control of legionella bacteria..
Legionella Monitoring - What Do You Need To Test?
When considering legionella testing it is helpful to understand the relevant legislative documents, some of the below are free and can be downloaded from the HSE website
- ACoP L8 – this is the main document for legionella referencing. In summary it tells what to do
- HSG274 part 2 – this is the main document referencing “domestic water services” such as your site. Not relevant to you would be Part 1 for cooling towers and part for 3 for “other” systems such as spa pools and hot tubs etc. Whereas the L8 tells us what to do the 274 tells us how to do it, when to do it and goes into more practical details
- “A guide for employers” – this sums up all the other details into a much smaller document!
- HSE INDG458 – A guide for Duty Holders – a small document again providing a brief overview of the legal requirements
It is very difficult to sum up such large documents here but essentially they state the following;
- Designated responsible person should have legionella specific training and understand legionella and the relevant legislation
- The designated responsible person shall ensure the site's legionella bacteria management is planned and a written scheme of control implemented
- Before any building can be occupied or open to the public or employees there is a legal responsibility for it to have a suitable and sufficient legionella risk assessment in place
- There should be a written scheme of control (this is normally created by a risk assessment and forms part of the logbook)
- The written scheme of control must include the following as a minimum o Weekly flushing of little used outlets for a time as defined by the legionella risk assessment
o Monthly temperature monitoring – To ensure all hot water cylinders flow and return are correct (stored at 60c+)
o Monthly temperature monitoring – cold outlets to ensure temperatures below 20c
o Monthly temperature monitoring – Hot outlets to ensure temperatures above 50c
o Monthly temperature monitoring – TMVs blended outlets to ensure temperatures within parameters and safe operation of TMV
o Showers and associated hoses to be cleaned using a combined descalant and disinfectant
o Six monthly TMV fail safe checks carried out on all TMVs
o Annual TMV full service including strip down, clean disinfection and reassembly
o Cold water storage tank inspection including temperatures and photographic report – photographic report to establish water tank compliance in line with HSG 274 parameters (see page 26 of the HSG274) - There should be a site specific monitoring record of all these items for a period of 5 years
Total Water Compliance - Legionella Control Experts
We provide tailored site-specific legionella bacteria monitoring programs where we come to your site and carry out all the relevant tasks and manage all documentation for you. This means you know your site is in safe hands and that you have Total Water Compliance. Total Water Compliance is registered with the LCA (Legionella Control Association) to carry out these tasks for you. We carry out these works for many different clients including;
- Hospitals
- Offices
- Schools
- Colleges
- Industrial manufacturing
- Marine industry
- Care/Nursing Homes
- Hotels
- Facilities Management Companies
- Airports
- Marinas
- Food & Beverage including breweries
- Shopping Centres
- Estate Agents
As you can see we can help you with your monitoring and water compliance in any sector!
What Is A Legionella Sample?
A sample of water would be taken in a specially prepared and sealed lab bottle and sent to a UKAS lab for analysis to test for legionella. This process can take up to 10 days to provide a result as the sample in filtered and incubated on various plates. The end result will tell us the type of legionella and the amount of the bacteria present.
Why Would Legionella Sampling Be Needed?
Stagnant water favours Legionella growth. To reduce the risk of exposure to legionella bacteria you should remove dead ends in pipe-work, flush out infrequently used outlets (including showerheads and taps) at least once a week and clean and de-scale shower heads and hoses at least quarterly. Cold-water storage tanks should be cleaned periodically and water should be drained from hot water cylinders to check for debris or signs of corrosion.
The site water systems may have further issues such as Dead legs: These are sections of pipework which lead to nowhere, eg. from outlets which have been removed but the pipe work to them still exists. Areas of buildings where water is not used frequently should also be considered as dead legs. Dead legs provide areas for water to stagnate and microbial growth to occur and multiply in the contaminated water, conditions well suite for the bacteria to multiply.
Should I Take Legionella Samples From My Water?
This is a question we are asked often! The relevant information can be found the within HSG274 Part 2 (page 40 or para 2.119 onwards). The sampling for legionella can be risk based and your Legionella Risk Assessment will provide advice on any sampling regime needed. Be aware that sometimes there is no requirement or need to sample. But in some cases sampling is required, especially in care homes and health care premises.
I’m A Care Home/Nursing Home, Do I Need To Take Samples?
Care homes will need to refer to their Legionella Risk Assessment for advice. Nursing homes however are required to take routine legionella samples as are hospitals and other such healthcare premises. The complexity of the system will need to be taken into account to determine the appropriate number of samples to take.
To ensure the sample is representative of the water flowing around the system, samples should be taken from separate hot and cold outlets rather than through mixer taps or outlets downstream of TMVs (Thermostatic Mixing Valves) or showers.
Additionally more information can be found on the Health and Safety Executive website where we are advised; Additional controls Water samples should be analysed for Legionella periodically to demonstrate that bacteria counts are acceptable.
The frequency of legionella monitoring should be determined by level of risk, in accordance with the risk assessment.
From our bases in Southampton, Portsmouth and London
Total Water Compliance can easily attend your site where qualified and trained engineers take the water samples for you and take directly to the accredited laboratory for the incubation period. Importantly we also provide legionella testing results interpretation so that can we work with you understand any microbial presence we find.
To arrange a no obligation quote or to arrange your Legionella Testing and Monitoring Scheme
Contact us HERE
Or call us on 0800 6102267