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Legionella control

Thermostatic mixer valve (TMV) servicing

What are Thermostatic mixer valves?

What are TMV’s and when do they need to be serviced? Thermostatic mixer valves (TMV’s) are devices used to accurately control the temperature of water by blending hot and cold water to a set temperature between 38°c and 46°c to prevent the risk of scalding.  Scalding can occur within seconds, especially with vulnerable users, by installing TMV’s ensures water is provided at a safe temperature.

What is the impact of a Thermostatic mixer valves on Legionella control?

The most common way to prevent legionella bacteria is through the control of temperature within hot and cold-water systems. Hot water must be stored at above 60°c as this will kill off any legionella bacteria in the system, and hot water temperatures must reach 50°c at the outlets to manage the risk of legionella bacteria.  However, the problem of scalding arises as clearly water at these temperatures could cause scalding, so this is where the two risks namely, legionella risk and scalding risk must be considered together and a solution found.

TMV’s are often used as a solution to prevent scalding but can themselves increase the legionella risk if not managed and maintained correctly.

The water in pipework downstream of a TMV being less than 50°c could provide a suitable environment in which legionella bacteria could multiply and therefore increase the legionella risk.  So, it is important to ensure TMV’s are installed as close as possible (less than 2m) to the outlet to reduce the legionella risk, while also managing the scalding risk.

Always consider whether the TMV is actually required, during the Legionella risk assessment the scalding risk will be compared to the legionella risk, if the scalding risk is considered insignificant then the TMV should be removed.

5 points to consider when fitting Thermostatic mixer valves

  1. The TMV should be part of the tap fitting if possible, to mix the water at the outlet.
  2. The legionella risk will be increased if a TMV is fitted to a low flow spray tap.
  3. The TMV should be fitted as close (within 2m) as possible to the outlet to reduce the volume of stored water in the pipework.
  4. The legionella risk is increased if the TMV valve feeds more than one outlet, for example, a bank of showers or wash hand basins.
  5. A TMV can inadvertently make a cold tap become little-used outlet that will need to be flushed weekly.

When should a Thermostatic mixer valves be fitted?

  • TMV’s should be installed within areas that present a high risk of scalding especially with full body immersion such as Baths and showers and particularly with very young or elderly people.
  • TMV’s can also be fitted to wash hand basins and sinks where a significant scalding risk has been identified, for example in properties with very young or very old people or in properties with mentally or physically disabled people.
  • TMV’s are required in all healthcare premises for example hospitals and healthcare centres.

When do my Thermostatic mixer valves need to be serviced?

The valves need to be checked on an annual basis or at a frequency defined by the risk assessment. It is important to ensure the valves are working correctly and will offer protection against scalding.

In hospitals, different regulations apply, and checks are bi-annual.

What is the difference between a type 2 Thermostatic mixer valves and a type 3 Thermostatic mixer valves?

Type 2 TMV can be overridden by the user. Type 2 TMV’s are only suitable for domestic situations and housing associations for able-bodied people. Products meet the standards BS EN 1111 and or BS EN 1287.

Type 3 TMV complies with the NHS document D 08 and has a pre-set temperature are fail-safe and cannot be overridden by the user.  Type 3 TMV’s are required in healthcare premises.  They are specified in the NHS Estates Model Engineering Specification Thermostatic mixing valves (healthcare premises).

For further information:

Health Technical Memorandum (HTM) 04-01 The control of Legionella, hygiene, ‘safe’ hot water, cold water, and drinking water systems Department of Health ‘Space for Health’ website (registration required) www.spaceforhealth.nhs.uk

HSE Managing the risks from hot water and surfaces in health and social care http://www.hse.gov.uk/pubns/hsis6.pdfThermostatic mixer valve (TMV) servicing

Please give our team a call on 01454 417 920 to discuss any aspect of TMV servicing or visit https://www.dantekenvironmental.co.uk/services/plant-equipment/tmv-servicing/ for more information

Children Washing Hands At School

Legionella control case study at a large boarding school

Dantek have provided legionella control services to Marlborough College for a number of years, below is a case study about how we work together to ensure ACoP L8 compliance and the safety of the students and staff.

Since its establishment in 1843 by a group of Church of England clergymen at the Castle Inn at Marlborough, Marlborough College has never been frightened of change. 

In its recent history, numerous academic initiatives have been fostered at the College including, Business Studies, SMP Maths, Combined Science, Pre-U examination syllabuses and the teaching of Arabic and Chinese. In 1968 Marlborough was one of the first of the traditional boys’ boarding schools to admit girls into the Sixth Form.

In 1989, the College became fully co-educational with the admission of girls into the Lower School and with the establishment of the first of the all-girl boarding houses.

Today the College caters for 936 pupils (of which just over 40% are girls) and the great majority of whom (98%) are boarders.  The remaining four “Out-College” houses accommodate 13-16-year-old boys, plus a mixed Sixth Form of both girls and boys.

School size: 201-500 employees

Based at: Marlborough, Wiltshire

The support Dantek provides

As a school, Marlborough College provides care for a large group of students most of which board on site, this means that they must adhere to strict health and safety guidelines. One of these areas is the need to protect students and staff from potential Legionella infection. Dantek has worked with the school for many years ensuring they comply with all regulations thus providing a safe environment for their students to thrive in.

As part of their on-going activity, Dantek engineers monitor the water quality, carry out remedial work and run regular testing and Legionella risk assessments. The College compliance team benefit from using Dantek’s electronic logbook which saves time and helps them keep on top of the various requirements. Dantek has provided a long-standing service to the college and act as part of their team which supports the quality of environment and interaction required by the College.

What does the client say?

We caught up with Kelvin Neale, M&E and Energy Manager at Marlborough College to find out how he views working with Dantek;

How did you hear of Dantek?

I have worked at Marlborough College for 8 months so Dantek were already in place when I joined. However, I did work with Dantek through another employer. I can certainly say that Dantek are known for their sound reputation in the industry.

What are the most important elements you look for in a contractor?

The most important elements for me are timely communication and a conscientious, effective manner. Due to the nature of the work Dantek provide, I also look for clear paperwork and accurate paper trial. We do consider the price, but it is not the only factor. When it comes to compliance, we must make sure we are choosing the right supplier who has the knowledge and systems which we require.

What do you like about working with Dantek?

I am very happy with their work in general. Three things stand up for me in particular:

  1. All engineers are professionals and knowledgeable, DBS checked and employed directly. They will always provide a service that goes beyond their contractual requirements and nothing we ask is ever an issue.
  2. The level of knowledge and expertise the company holds is impressive, they clearly know their stuff. I am also very impressed with the fact that on the rare occasion when they come across something they don’t know; they will go away to research for the right solution. It really demonstrates how competent they are and allows me to trust their advice implicitly.
  3. The electronic logbook is helpful and saves me a lot of time. It means I always have the data I need available to me and we never miss any tests and activities we need to complete.

How do they stand out against the competition?

As mentioned before, Dantek has a strong reputation in the industry. I think the main elements that make them stand out for me are as follows:

  1. The concise and timely completion of every job
  2. The electronic logbook which allows me to stay on top of compliance requirements, documentation and paperwork
  3. The level of knowledge and expertise they demonstrate about water treatment and legionella control
Marlborough College Case Study (PDF)

 

Public Health England report on Legionnaires’ disease

How many cases of Legionnaires’ disease were there in 2018?

Read about the latest number of confirmed cases of Legionnaires’ disease in England and Wales since January 2018. The report gives a breakdown of where the cases occurred geographically and how it was contracted, for example, whether it was through travel or in the community.

Monthly legionella report November 2018 (PDF download)

Do get in touch if you have any concerns about how to prevent and control legionella bacteria and what you are legally required to do to keep your water safe.

New office in Staffordshire

Expanding Legionella Control Services in Staffordshire

Legionella control Staffordshire: In response to the successful expansion of our business in the Midlands region over the past year, Dantek is proud to announce the opening of a new office in Staffordshire. This strategic move allows us to better serve both new and existing clients in the Midlands area. Over the initial 12-month period, our central team has secured multiple contracts.

With over two decades of collective experience in legionella control, our Midlands team is led by Holly Jakes, a seasoned professional with a decade of tenure at Dantek. Holly’s unwavering dedication to maintaining the highest service standards and preventing Legionnaires’ disease has been instrumental in driving our growth in the region, all while upholding Dantek’s core values.

Reflecting on our achievements, Holly remarked, “The past year has been marked by significant success, with Dantek’s reputation in the Midlands spreading through word of mouth and recommendations. Our comprehensive services cover all aspects of legionella control, from risk assessments to monthly water monitoring, water treatment, cooling towers, and plumbing remedials. While we benefit from the support of our Thornbury head office, our local management ensures a seamless experience for our clients, from initial inquiry to project completion.”

Based in Cannock and Gloucester, our central team continues to expand, collaborating closely with local businesses, schools, and universities to promote water safety and hygiene.

For more information on how Dantek can assist you in safeguarding your water systems, please contact sales@dantek.co.uk.

http://www.dantek.co.uk

Employee profile: David Edwards Legionella Risk Assessor

Legionella L8 assessment
Legionella risk assessing

When did you join Dantek?

I have been working at Dantek for 10 years, I started doing monitoring, tank cleaning, remedial works and cooling tower disinfections. I then progressed into Legionella risk assessing about 5 years ago.  Before joining Dantek, I was at another company cleaning and disinfecting cooling towers and carrying out remedial works on cooling towers as well as tank cleaning and disinfection work. So, by the time I came here as a lead engineer I already had a wealth of experience in the industry.

Becoming a Legionella risk assessor?

Most of my training has been on the job, I started at bottom and have worked my way up by building on experience. I am a qualified plumber so that really helped with my career as it meant I have a solid understanding of how buildings are plumbed and how water systems work. Particularly now as a risk assessor I can easily identifying risk as I know what looking at. I have done every single aspect of water hygiene so can draw on my knowledge when risk assessing a building.

I have spent years of my life stripping cooling towers and working in cooling towers so risk assessing them came very naturally as I have a thorough understanding of how they work.

Of course, I do have formal qualifications in legionella risk assessing but I firmly believe the best way to learn is from practical experience rather than academic study alone.

 

Where do you start when carrying out a legionella risk assessment?

I tend to start in main plant areas and work my way from there, generally they are the biggest areas of risk. Start with tanks and calorifiers and then move to identifying blinds ends, dead legs and return loops.  I will also request to see any records or previous risk assessment on the building which can be a helpful starting point, although of course it needs to all be updated and schematics drawn to ensure they are accurate, and everything is up to date.

 

What challenges do you come across?

Cooling towers are challenging, as the legionella risk is potentially so much higher.

Buildings can also be deceptive as a straight forward looking 2 storey building could house any number of systems for example; there could be a lab or have reverse osmosis system, so you need to wait until you discover what is inside.

 

What work are you most proud of?

Herm Island is definitely my proudest achievement as I have risk assesses every single property on the Island.  All the water is fed from a bore hole, so it has its complications.  I go there every 2 years to update the risk assessments and am so impressed as they have carried out all the recommendations I made in my initial risk assessment. Given they cannot just pop to B&Q as they are an island, they must ship every single part and material in order to do all the remedials, but they have done it all and taken everything on board, which I am afraid to say not everyone does so thoroughly.

I also enjoy going into places and finding tank, calorifiers and even taps that people are unaware they even have.  I am often told there are “no tanks in our building” only to find there were hidden behind a panel or roof space.  It is really satisfying to know you have done a thorough job and being naturally inquisitive has helped me to make sure every tank, calorifer and tap are assessed.

 

What are the best features of our risk assessment reports?

I think customers find the asset register and photos useful as it clearly sets out exactly what you have on site.  The risk score is also highly valued by customers because it shows what your risk is now and what your projected risk could potentially be if you put in place the control scheme suggested and carry out the remedial work.

We also explain why the risk score has been given with an in-depth explanation for customers. I think this is good because it helps to prioritise where to take action first to make the most impact to reduce the risk on their sites.

 

What do you enjoy about your job?

I love the freedom of the job and being out and about visiting different places.  I like the trust the responsibility of the job and the satisfaction of knowing the work I do can make a difference by helping to ensure no one suffers with Legionnaires’ disease.

 

What do you like doing for fun?

I really enjoy sea fishing and try to do as much as I can.  I support Cardiff City both at home and away.  I am currently planning a holiday to Vietnam for next year which will be a great experience and hopefully I will be able to fit in a bit of fishing while I am there.

How much should a Legionella risk assessment cost?

 

How long does a legionella risk assessment take
How much is a legionella risk assessment?

Your concerned about compliance and you want a good company, but still, budgets are tight, you need the best value, so what do you need to tell contractors to get a fair price? Or get quotes you could compare? And how do these people work it out anyway? I will attempt to throw some light on the occasionally opaque world of Legionella or water risk assessment pricing.

As a start point I have assumed that you are only going to be dealing with reputable contractors who are specialists in the industry, generally members of the Legionella control association, possibly UKAS accredited, who can prove they are competent and have a solid track record. There have been operators in the marketplace who will ‘buy’ risk assessment contracts with the intention of raking the money back on follow-on works and contracts, this is a clear conflict of interest, and I advise avoiding it.

A Legionella risk assessment is a form of consultancy, which means it is, for the most part, a labour only service. This means the big question is – how long is it going to take? Once we figure this out, multiply the time by a day rate and bingo! A price.

Top tip; Ask what the standard day rate is for a surveyor, but be careful, some include administration time some don’t.

Estimating how long a survey will take is a fine art, but there are some variables to consider:

Geography

Where is the site? Or where are the sites? Travel time is working time, and you pay for it. Ideally, you’ll use someone local if you have a big single site or cluster of buildings, but sometimes this isn’t practical. If you have many disparate sites, you can get some great economies on a round robin or road trip type basis. Also, these are fun for the surveyors. Years ago, I risk assessed every driving test centre in Scotland on a road trip basis and had a great time.

Once you understand the logistics of getting the surveyor to and from the site, how long will they be there? The two big factors in this debate are; what water services have you got? And how hard will they look? The second point can be contentious, so I’ll deal with what you’ve got first.

Water Assets and system complexity

I have seen many different approaches to convey what is on site, varying from line item asset registers, copies of the previous risk assessments to lists of the gross internal areas of properties. The surveyor’s point of view generally stems from, how difficult is this system going to be for me to understand and how many assets do I have to survey? For example, a large modern office block could seem like a big beast but in reality, may have plant room in the basement, a single wet riser by the lift shaft, toilets and kitchenettes on each floor plus a couple of cleaners cupboards, simple. In contrast, a stately home converted to halls of residence can contain multiple systems and a dog’s breakfast of assets and pipework that would reduce the finest to tears.

Top tip: Give what information you have, including building use, number of stories, and location

 

The industry refers to all hot and cold-water systems for toilets, sinks, showers etc. as domestic systems. These are almost universally included in risk assessments, but what about cooling towers, industrial uses of water, humidifiers, water features, medical equipment? The survey should cover all water assets one way or another.

In the industry, we benefit from huge amounts of experience so in talking about your buildings we build a picture of what we are dealing with, by being as honest and open as you can you will get the most realistic estimate possible.

The depth of the survey

If you have been on the forums this is a hot potato; the fastidious independent contractors shout down the ‘stack’em high sell it cheap’ brigade for being cowboys and the quick ‘all done on an iPad survey’ crew retort about over-egging the pie. The truth is the risk assessment must be suitable and sufficient, just as the lower the risk, the less you have to do, the converse is also true. There is a place for the iAuditor type surveys on lower risk properties, retail outlets, provincial train stations and minor highways depots etc.

Conversely, if you’re looking after NHS estates, your burden is much greater. The best advice I can give is to view example documents on properties similar to yours, talk to the contractor and understand what they intend to return. You need to feel comfortable the contractor has your best interests front and centre, and they are not ‘flogging you what they’ve got’.

Begin with the end in mind

The Legionella risk assessment certainly ticks a box for compliance but if done well is a tremendous source of information regarding your water assets. Think about practical outputs, for example, how do you expect to see non-compliances reported? Do you want them separated in a way you could pass to a mechanical contractor or your onsite plumbing team?

Talking to your suppliers about Legionella control in a wider context beyond the risk assessment can pay dividends in understanding how the document could support your efforts to implement a successful control regime later on. You’ll be amazed what you can get for free during the risk assessment process just by asking, consider;

  • Do you want accurate schematics drawn in AutoCAD?
  • Would it be handy if the pipe runs are overlaid on your existing building schematics?
  • Would you like an electronic copy of the asset register in excel?
  • Do you want the assets in an electronic logbook as part of the deal?

A word about water samples

There is no hard or prescribed requirement to take microbiological samples during the risk assessment process, in our company we don’t take them as a matter of course but others do. I could write another thousand words on the pros and cons of sampling, but ultimately, to compare quotes you need to understand if they have been included for and if so how many. The current market rate for a Legionella test at a UKAS accredited laboratory is about thirty pounds so cost can be significant if a meaningful number of samples are taken.

 

At the end of the day

All risk assessment quotes have at their core an estimation of how long the survey is going to take and the report to produce, as a buyer you should understand and be comfortable that your supplier will do a job that is acceptable to you in the time they have quoted. At the bulk end of the market, if you are paying one hundred pounds or less for a risk assessment, your contractor is expecting to do four or more sites per day and is not expecting to find very much. Industry rates vary from three hundred to six hundred pounds per day for a qualified Legionella risk assessor as a guideline.

There are many decent companies out there all of them should welcome sensible discussions on the big question – how long is it going to take?

Dantek are a specialist provider of Legionella control services including Legionella risk assessments.

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NHS Trust fined £300k for failure to control legionella bacteria

Legionnaires disease fatality
HSE fine NHS

Royal United Hospitals Bath NHS Foundation Trust has been fined £300,000 after failing to control the risk to patients from exposure to legionella bacteria in its water systems.

Bristol Crown Court heard how, in July 2015, Mr Terence Brooks, a 68-year-old patient at Bath’s Royal United Hospital, died from legionnaires’ disease. Following Mr Brooks’ death, the Health and Safety Executive (HSE) launched an investigation which found that the Trust had failed to put in place all of the necessary precautions to minimise the risk to patients in the annex to the William Budd ward from exposure to legionella.  For full details about this case see the HSE bulletin below:

http://press.hse.gov.uk/2018/nhs-trust-fined-after-exposing-patients-to-legionella-risk/?utm_content=&utm_medium=email&utm_name=&utm_source=govdelivery&utm_term=

Mark Couchman invited to speak about legionella control

Our customer AFM have asked Mark Couchman to speak about “Legionnaires’ disease – roles and responsibilities” at an event they are holding on Jersey and Guernsey as part of World FM day.

Mark said “This is a great opportunity for people to learn about legionella control and what they need to do under current guidance -I am looking forward it and feel pleased to have been asked to take part”.

The event takes place on 26th/27th June.

What is World FM day?

World FM day legionella control
Mark speaking about legionella control.

World FM Day is a Global FM initiative to celebrate the importance of the FM profession. It aims to raise the FM profession profile around the globe, promoting facilities management’s ideals, not only within the profession and industry, but also among governments and the general business community. World FM Day takes place in June every year.
Objectives of World FM Day
• To draw attention to the aims, objectives and progress of the facilities management profession around the globe
• To highlight the valuable contributions sound facilities management has made and is making to sustainable global communities; productive, safe, healthy and secure work environments; and local and global economies
• To give worldwide coverage to the ideals of facilities management, not only within the profession and industry, but also to governments and among the general public.
Who can take part in World FM Day?
Every FM professional, organization working in the FM area and FM associations around the world can celebrate World FM Day and use the World FM Day logo.
How is World FM Day be celebrated?
FM associations will celebrate World FM Day by organising events, such as luncheons, seminars and workshops, Twitter debates or by undertaking any other activity to celebrate and promote facilities management.

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