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WMSoc Questions and Answers

The advice offered in this section has been drawn up in the spirit of general guidance. If there is any doubt, in any case, expert advice must be sought.

Responsibilities

Q1) The Responsible Person

When looking to draw up a management structure recently the following question arose. Where a Council has delegated the management of its Housing stock to an ALMO Organisation, who becomes the responsible person the Council or the Almo (outsourced facilities management company), and if it is the Council is there a need for a named individual to take ultimate responsibility?

A1)

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Q2)

For the client/employer/controller of workplace premises to use a contractor as the ‘Responsible Person’ under L8, what authority and power would the client have to allocate to the contractor in order they can actually fulfil their duties?

A2)

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Q3) Responsibilities

Could you please let me know who is responsible for the legionella testing and health & safety in a building, which consists of individual flats and common areas? (The flats are supplied from a common main, but each flat pays rent that includes the water supply. They also pay their own electricity. This includes water heating).

A3)

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Multi-occupancy Buildings

Q1) Towel Rails

I have a couple of issues that have been put to me by a consultant and wondered if you could help?

The building in question is a residential block of some 75 flats, currently served be two massive calorifiers that are now well past their sell by date, it is our intention to replace these with direct fired hot water generators. The system currently includes towel rails that are connected to the open hot water system. We have been advised that the towel rail should not be connected to the water system and that this is in accordance with currently imposed regulations. I have been through the regulations and cannot find any reference to this claim. Can you help?

In addition when we disinfect the new generators do we have to disinfect the entire distribution network including the cold water services? There may be a situation where, when disinfecting, there is cross contamination through mixer taps.

A1)

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Q2) Council/housing associations & Legionella risk assessment

Should all properties under the control of Council Housing Associations (2500 domestic dwellings in one case) have a legionella risk assessment carried out?

Also what monitoring regime should be initiated (if any) for the water systems within these properties?

There is a mixture of multi occupancy flats with communal storage tanks and calorifiers, individual houses with their own tanks and calorifiers, and flats/houses with mains fed cold water services.

A2)

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Q3) Retirement Homes

The interpretation and application of the ACOP L8 in Retired Development and private dwellings is becoming something of a trial to all concerned and I would appreciate clear guidelines.

We live in a Retirement Development of 38 Flats. Each living is independent of the other. Each Flat with its own tank and water supply, and each heating their water supply as required.

We understand why the 300lt limit was removed in 2000 and can see the practical application and the benefits in the case of Residential Care Homes, Pre-School Nurseries, Nursing Homes, small businesses etc. where there might be one or two water tanks and the water heated to constant temperature. But in a Development of 38 Flats, each living.

A3)

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Q4) Hot Water Temperatures in Care Homes

What hot water temperatures do I need achieve in a Care Home I am responsible for?

A4)

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Q5) Care Homes and Water Temperatures

What is the correct temperature for hot water in a care home, to control the risk of legionella and avoid the risk of scalding?

A5)

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Q6) Multi-occupancy - Residential Flats

I am the chairman of the Management Committee of a block of residential flats. The building is made up of three side-by-side blocks, seven stories high. On the roof we have six tank rooms containing water tanks that hold over 2000 litres each, fed from the mains supply. Our Managing Agent has told me that because we are the representatives of the Owner and we are supplying water to each of the 55 flats within the blocks, legislation demands that we have a Legionella risk assessment programme. Mains water is also fed directly to each flat.

We have had a survey and risk analysis done, but the company who carried it out are suggesting that we should include temperature checks on all water taps within all the flats every six months. We believe that this far exceeds our responsibility and is largely motivated by commercial factors.

I would greatly appreciate some guidance on what we are obliged to do, bearing in mind that we are only responsible for the supply of cold water to residents.

A6)

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Q7) Multi-occupancy Buildings

In a high-rise block of flats, how many hot water taps should be checked and how often? Gaining access to private dwellings is proving difficult, due to being seen as intrusion.

A7)

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Q8) Care Homes and Dip Slides

Is water testing for legionella or with dipslides necessary or desirable in a care home of the elderly?

A8)

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Q9) Care Home Hot Water Systems

A Care Home has been advised to keep water temperature down to 43-44OC at the hot taps, to prevent scalding. The owner is aware that water must be stored at 60 OC and recirculated at 50 OC to minimise potential problems with Legionella in the pipework between any temperature control valve and the outlet(s). How does he reconcile the apparent differences in demands?

 

A9)

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Cooling Systems

Q1) Cooling Systems

Are there any concerns about the use of Antimicrobial Fill Pack for Cooling Towers?

A1)

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Q2) Cooling Towers

If a cooling tower or evaporative condenser is standing idle, how often should it be put into operation?

A2)

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Q3) Cooling Systems

I have recently commissioned a report upon the operation of two Cooling Towers I am in charge of, with a view to test the competency of the contractor who is managing them on my organisations behalf. It has thrown up a number of areas of improvements, that I am unclear as to how significant they are and indeed the contractor in question is disputing that some of them are in fact true or relevant. I would be grateful therefore if you can find someone to offer an impartial view upon their significance and correctness.

The main areas of concern are: 1) I am located in a hard water area and the contractor has been dosing using treatment chemicals and Bromine Tablets. The report states that this regime is not ideal for a hard water area and one of the treatments, if anything would be used for de-scaling the tower and is not a recognised inhibitor. The other has H&S implications with manual handling and fuming and there are interaction issues with the Bromine. The Bromine can oxidise with the biocide greatly reducing its efficiency. The contractor providing me with this regime states that this method of control is perfectly safe and acceptable and refutes any of these statements. A third opinion would be handy?

2) The Bromine Drums were either left open or had had access flaps cut into them. My report also states that it is bad practice to use tablets and ACOP L8 recommends liquids. The contractor refutes that ACOP L8 states this and that it is an issue. Which is correct and is this big a issue?

3) I have no bund walls present. How significant is this?

4) I have poor site management i.e. no displayed COSHH handling sheets, no displayed emergency numbers, no schematic drawing in the plant room etc. How significant is all this, is it a requirement or best practice? The contractor doesn't see these as big issues and is happy to provide them if I want them.

5) There are holes log book - There is no schematic - the contractor says there is one in the risk assessment. Should there be one in the Log Book? COSHH Sheets are not in the Log Book - Should they be there? Responsibilities are not filled in - Is this significant?

The question I am asking myself here is am I on the right side of L8?

There are many other issues that have been picked up, but I think these are enough to give you a flavour of where we are. I appreciate that there is a lot here for comment, but would be very grateful if you could find someone to afford me five minutes. I would not hold them to any comments that they make.

 

A3)

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Q4) Cooling Towers

I am H&S consultant to a company in West Yorkshire, who operate a small cooling tower installed in 1987. Passage of time and changes of staff mean that the current maintenance regime is something that has been passed down by word of mouth over the years and I am concerned that the practices followed may be inadequate particularly in respect to control of legionella.

I have been unable to trace successors to the manufacturers to get advice from them. Can you make suggestions as to whom I should contact to get information that will help us to confirm that current practices are adequate or, if not, to set up appropriate treatments and records?

A4)

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Q5) Removal and decommissioning of Cooling towers

Is there a procedure for the removal and decommissioning of cooling towers? Are there any legal aspects we need to be aware of?

A5)

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Q6) Cooling System Controls

Have you heard of document produced by EHO in central London apparently making the following recommendations:-

Monthly TVC samples on cooling systems.

The use of a non-oxidising biocide with oxidising biocides?

You kindly responded to a previous question regarding non-oxidising biocide and we have not been using this form of biocide, but we have been very heavy criticised by one of our central London clients. We are using oxidising biocide successfully and using monthly dipslides as a further check along side the sites weekly dipslide results.

A6)

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Q7) Cooling Systems and the powers of EHOs.

The EHO for my area of London has requested daily visits to monitor a cooling tower on a site we maintain. Can you advise on recommendations with regard to monitoring and testing intervals?

 

A7)

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Q8) Biocides in cooling systems: Chlorine activated bromine micro-organism control mechanism.

I have a client in the city of London where we are running a chlorine activated bromine micro organism control mechanism.

The system has on line filtration, redox and conductivity control. Generally culture slide results are less than 10cbm3 and 4 consecutive months testing for legionella has not detected any contamination. In view of the L8 116 should I be dosing a secondary biocide to act as a surfactant? According to the Nalco handbook chlorine activated bromine programmes will penetrate bio film section 22:12. By not dosing a secondary biocide would I be leaving myself open to criticism.

We are also dosing a product for corrosion/scale control which has dispersant properties.

A8)

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Dead Legs

Q1) Dead-legs

What are the recommendations regarding dead-legs?

A1)

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Q2) Dead-legs

Would an unused washbasin in a vacant room be a dead-leg?

A2)

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Q3) Dead-Legs

The water supply to feed and expansion tanks and close system pressurisation units are infrequently used. What advice could you give us on the way to approach this when carrying our a Legionella Risk Assessment? Do we treat the supply to these tanks as deadlegs?

A3)

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Calorifiers and Hot Water Systems

Q1) Calorifiers

Why is it ,that the hot water secondary water always returns to the centre of the calorifier and not to the base. This would eliminate the use of de-stratification pumps.

A1)

HWSR lines connect to the calorifier at mid or upper level so that the circulation does not disrupt stratification and the hot water can float on cold water at the base. Connecting them at lower level mixes the entire contents of the vessels, so any hot water usage and consequent cold water make up cause a reduction in temperature throughout the stored water, making the thermostat switch on and then off at very frequent intervals, an effect known as "hunting".

Q2) Hot and Blended Water System Temperatures

Can you tell me the required Hot Water and Blended Water Temperatures in building systems?

A2)

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Q3) Calorifiers and Water Temperatures

Please could you help? I have a client who operates a hot water system, which is pumped and reaches 50oC on the calorifier return during the week. At weekends the system heating is turned off, but water can still be drawn to outlets if there are workers on site, but these will be few in comparison to the usual workforce.

I have been asked whether this is acceptable add find it hard to judge in view of the following:-

Paragraph 154 (L8) indicates that periods of less than 1 week may be acceptable. However, paragraph 169 recommends storage at 60oC and tap temperature of 50oC within 1 minute. This would not be the case at weekends.

Further, paragraph 185(6) recommends weekly lp tests where the control regime is not consistently achieved, which would happen at weekends.

A3)

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Q4) Calorifiers.

Please could you comment on the following?

I have a client who has a number of older style calorifiers, which have a pumped ring main returning to the middle of the calorifiers.

Would it be acceptable to re-pipe the return water into the cold water down service feed provided non-return valves are fitted? Or should I insist that shunt pumps be fitted?

A4)

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Q5) Electric Water Heaters

We have a problem in so much that when taking temperatures of small electric water heaters the delivery temperature is often 46 - 49 deg C, possibly due to a recent use and insufficient time to allow the water to heat up again.

As there is no adjustment on these, how much time should be left from it's last use which could have emptied it until a temperature is taken? How much under the 50 deg C is acceptable?

A5)

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Q6) 'Fortic' Tanks

Please could you help me with the following?

I have recently carried out a risk assessment and compiled a scheme to minimise the risk from legionella, for a housing association. The property is sheltered accommodation for the elderly where the occupants have their own flat/bedsit.

Hot water is provided in each flat/bedsit by individual fortic tanks.

As the temperature in the cold section in each of these tanks is around 360C, usage could be small and stratification in the hot water part of the system could occur, I have identified this as a high risk of legionella proliferation.

The landlord has asked whether these tanks could be excluded in the assessment as they are residential flats and they do not consider themselves responsible for the necessary monitoring and treatment considering the risk identified?

A6)

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Q7) Fortic Tanks

Would you treat the cisterns on top of "fortic" style heaters and flatbacks the same as main cold roof tanks /cisterns, with regard to legionella management.

Assuming that the heater is used on a regular basis and the hot water temperature is correct would they need to be checked for cold water temp twice-yearly etc. Invariably there is a heat transfer from hot to cold sections and correct temps in the cold tank are difficult to achieve. Is this negated by the pasteurising effect of the heating process?

A7)

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Q8) Scalding

At what temperature would water scald? The personnel coming into contact with the water are people of working age.

A8)

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Q9) Calorifier vents

Could you tell me where it is written that calorifier open vents must be direct to drain via a tundish?

There is a diagram in ACoP L8 implying this but the Water Regs and the Fittings & Materials Directory have plenty showing the vent going back to the cold water storage cistern.

 

A9)

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TVC Levels

Q1) TVC levels

A UKAS accredited laboratory has just informed me that there are no limits For TVC levels now but they still use the old limits of 100 & 1000 cfu/ml as a guideline. Is this correct? What actions would you recommend be undertaken, on the hot and cold water systems and associated storage vessels, if the test results show levels above these guidelines e.g. 3840 at 37°C and 2400 at 22°C?

A1)

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Cleaning and Disinfection

Q1) Disinfection of Water Supply Systems

Could you please confirm if there is a British Standard or ACOP covering the disinfection or sanitisation of water supply systems?

A1)

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Q2) Mains Water

What is the procedure for chlorinating mains water systems?

A2)

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Mains Water Temperature

Q1) Mains Water Temperature

The temperature of the incoming mains water to my site is often at or above 25oC during summer months. What can I do about this?

A1)

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Q2) Mains Temperature

I have a client who owns three 25 storey tower blocks in London.

Last summer I recorded incoming mains water temperatures over 20°C. I wondered if you had any comments/guidelines regarding this problem or could put me in touch with other Members that have experienced similar problems?

A2)

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Drinking Water and Mains Fed Equipment

Q1) Drinking Water

Can WMSoc supply a set of guidelines that clearly outline the tests required when having drinking water analysis conducted on our premises?

A1)

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Q2) Mains fed showers

I have a client who has installed mains fed electric showers. I have recommended they run the showers weekly at 50 deg C as a measure to prevent legionella contamination. They recently had a low level of legionella in one of the showers. The installers have stated that 50 deg C will not be achieved as the max temperature setting is 48 deg C. They refer to water regulations Ref R18.5/G18.5 that terminal fittings at the outlet should not exceed 43 deg C.

A2)

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Q3) Mains Fed Equipment

I am a trustee of a registered charity providing community services from a 'shop' fitted as an internet cafe.

I should like advice please whether the two devices we use would require us to take action under the regulations outlined in HSE Pamphlet IAC27(rev2) - "A Guide for Employers".

First device. A water main fed, electric powered, hot blown air hand dryer of the type widely fitted in washrooms across industry, pubs and public buildings etc. Although it does NOT emit a spray of water it does cause water on the hands to be vaporised presumably taking bacteria with it and spreading at least as far as a fine spray. If this device is seen as a threat, what possible precautions can we take short of taking it out of use and reverting to less hygienic towels. We can hardly ask users to stop breathing while drying their hands.

Second device. A water main fed perfectly standard ceramic wc with conventional low-set cistern holding flush water until flush operated by a handle. No spray is generated but it is possible that the tumbling flush water will cause droplets to be thrown up. We could ask ladies to remain seated until the flush has finished (perhaps not) and ask gentlemen to lower the seat cover before flushing.

A3)

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Q4) Tanked Drinking Water

A4)

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Cold Water Storage Tanks

Q1) Water Tanks and Monitoring

What are the requirements for the monitoring of water storage (header) tanks? Where do they come from?

A1)

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Q2) Tank cleanliness and stored water

I have recently chlorinated a development of a block of brand new apartments, which have boosted water and an 8000ltr break tank.

The developer has called me and explained that the water tank and booster system that has been recently chlorinated will not be put into full use until 3/4 weeks time.

I have explained the tank requires a regeneration of water every 24hrs.

1. While this tank is out of use would it have to be drained down?

2. Would it have to be re-chlorinated?

3. Can it stay filled but with a dose of chlorine added?

4. Can it stay filled and then put into operation in 3/4 weeks time?

A2)

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Q3) Cold water tanks, storage and L8

We are currently running cold water tanks serving potable water to prison cells. If temperatures are not maintained to current guidance as outlined in HSG274 Part 2 what preventative measures do we take? If we are supplying non potable water from a storage tank what maximum temperatures are permissible? If they are not maintained what measure do we take?

A3)

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Disinfection

Q1) Cleaning & Disinfection

What is the origin of 50 mg/l and 25 mg/l free residual halogen for cooling water system disinfection?

A1)

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Elevated Cold Water Temperatures

Q1) Elevated Cold Water Temperatures

There is an outlet in a laboratory which is situated a considerable distance from the CWST and suffers from considerable heat gain, especially in summer, and has been above 20ºC for the last two monthly temperature surveys – ranging between 23 and 27ºC.

If the outlet is left to run the outlet temperature reaches tank temperature in approximately 5 minutes.

Is asking the lab technicians to purge the outlet (with minimal aerosol production) before use acceptable or does the increased risk of contamination prohibit such procedures?

The pipe run has been checked and there are no obvious unlagged sections or areas where the hot and cold piping is too close. Are there any engineering measures which could be implemented in this situation?

A1)

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Removal of Cold Tanks

Q1) Removal of Cold Water Tanks

Over the last few years we have been taking out most of the cold storage tanks from our schools where reasonably practicable. We are now wondering whether the ClO2 (which was introduced as an interim measure) should continue to be used in those schools where the tanks have been removed.

A1)

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Disinfection

Q1) Disinfection of Cold Water Storage Tanks

How do I disinfect a cold water tank in a hotel?

A1)

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Q2) Disinfection of Down Services

When disinfecting the down-services of a building is it acceptable practice to neutralise the chlorine and leave it in non-potable water?

A2)

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Q3) Neutralising free chlorine.

When sodium thiosulphate is used to neutralise free chlorine in water will it also help destroy combined chlorine, ie chloramines?

A3)

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Q4) Silver-hydrogen peroxide

I am looking for some advice on a new product.

A sales man has approached us from a company offering a product for the use in chlorinating cold water storage tanks. Apparently this product negates the need for physically cleaning the tanks too; I cannot see how this is possible.

We are wary of any product like this that contains silver traces, as silver is basically a poison. At the minute we would only use Sodium Hypochlorite for the chlorination of cold water storage tanks.

Is this product recognised as an acceptable product to be used in the control of legionella under L8?

A4)

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Q5) Chlorine dioxide in Schools

We have chlorine dioxide injection into water systems serving schools. The levels of treatment are maintained automatically via redox units. Once these dosing systems are installed, do the taps in the system still have to be turned on for a short duration every week?

In particular, during school holidays when the premises are hardly used, would it be a requirement to continue turning on the taps every week? Does dosing the water ensure that the water quality remains an acceptable quality?

If the water is being dosed continually with chlorine dioxide, is there still a risk of legionella growing in the system?

A5)

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Shower Descaling

Q1) Descaling of shower heads in primary schools

With regard to the cleaning of showerheads, if I was to replace the showerheads with brand new ones four times a year, am I complying with the regulations?

 

A1)

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Other Systems

Q1) Fire Fighting Systems

The information in L8 regarding Fire sprinkler systems is scant. Can you give some extra guidance?

A1)

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Q2) Fire Sprinkler Tanks

I have been asked questions with regards to the maintenance requirements for sprinkler water tanks. I cannot find any reference to them in L8. Should the customer be treating this tank as any other or are specific guidelines set down? If so where can they be found?

A2)

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Q3) Water Features

Are there any requirements to test for Legionella in natural outside ponds(with fish in etc) /water features?

A3)

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Q4) Indoor water features

I have a question with regard to indoor water features in atrium type premises. The water is re-circulated and bubbles out of a small nozzel at the top of a decorative sculpture - what regime should be adopted for ensuring that bacterial growth is prevented?

A4)

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Q5) Water treatment for indoor waterfalls.

I am part of a team of people tasked with engineering new ideas to treat our companies 5,000 gallon waterfall.

We are looking for a treatment system that will remove the pond water smell of the water and not have a chemical order either. The water falls on to marble tile so it can not produce any discoloration as some electronic pulse water treatment systems do. Our system utilizes a storage tank/pump unit that lifts the water up to a twenty foot waterfall.

Do you have any designed water treatment systems that will help us that are chemical free?

A5)

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Q6) Indoor water features.

I'm putting a water feature into an indoor restaurant and wanted an expert opinion on the best way to keep the water clean, safe and scale free. It's in a very hard water area.

The wall is 4m wide by 3m high with a water reservoir of 500 ltrs (4m x .35 x .35). The water is at room temperature and is pumped round at about 110ltrs /m. People may touch the water but it will not be consumed.

I've been told that distilled water may be the answer to the scale problem. If this is the case where could I get a supply of 500 ltrs for delivery to Hampshire?

A6)

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Q7) Process Water - Slurry

Slurry is produced from a chemical called promol and water. This is used to stop the rubber particles produced in manufacturing mills sticking together. Microbiological testing was carried out on three separate samples collected from the mills.

Can you help me with the following questions?

Does the high TVC count suggest there is presence of various bacteria's present in the slurry? The testing was carried out at temperature of 37 degrees. The manufacturing process involves the slurry heated at higher temperatures, will the bacteria not die at higher temperatures, thus eliminate the possibility of inhalation of bacterial droplets?

The possibility of the bacteria to be harmful to health will not be the case, as its presence in the steam generated at high temps will kill them. Can you give me any information on this please?

A7)

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Legislation and Guidance

Q1) Legislation and Guidelines

Please can you provide details-regulations on the correct labelling of taps on the following premises?

Hot water, cold water, storage tanks, non-drinking water and drinking water etc.

1. Hotels

2. Nursing homes

3. Residential homes

4. Care homes

5. Sports facilities

6. Offices

A1)

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Q2) The Irish L8

Is there an equivalent to L8 in use in Ireland?

A2)

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Risk Assessment & The Written Scheme

Q1) Risk Assessment

Is there a set format for conducting a Risk Assessment annual review/update as applied to buildings, i.e. what procedure is required to conform with ACOP L8 2001 as far as documentation is required?

Are we required to take water temperatures and bacteria tests etc?

We understand the requirement to report on changes to the building and system, but how far do we go with the already assessed systems without creating a completely new risk assessment?

A1)

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Q2) Legionella Risk

At what levels does legionella become a problem to human health?

A2)

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Q3) Risk Assessments

How often should audits be carried out?

The LCA state that a review should be undertaken at least annually, and in L8 there is no reference to review frequency (apart from risk assessment frequency). Is there any necessity or requirement to audit/review on a set frequency or is it annually unless there is a reason to review more frequently if higher risk or problems found?

A3)

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Q4) Negligible Risk

Sorry to be a pain but how can we decide what level of risk is negligible, this is the detail I am struggling hard to ascertain.

Being self employed surveyor looking at my PI cover has made me question things in great detail but in this case the possibility of infection is my prime motive. Would a consultant advise upon level of risk for occasionally used sinks etc. and if so how would he do it?

A4)

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Q5) Schematic Drawings

Are schematic drawings required for systems that have been assessed as of no risk?

A5)

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Q6) The Written Scheme

Please can you advise of whom, in your opinion, should write the written scheme?

A6)

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Q7) Risk Assessment of Outside taps etc.

We have had our main buildings risk assessed for legionella but I am not sure if such items as outside taps, standpipes in our parks and gardens, isolated sinks in stores which have mains fed hot water heater, etc need to be risk assessed.

A7)

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Legionella and Microbiological Monitoring

Q1) Legionella Sampling and Routine Monitoring

I am at present carrying out an audit on various procedures. Many of the procedures I had created over time, but the one relating to the taking of a legionella sample was derived from previous material and I do not know of its original source. I was wondering whether you know of any procedures relating to the optimum method of taking an lp sample. The main contentious area of our current procedure is the timing of the taking of the sample from the water flow. Our procedure refers to running the water flow for 2 mins.

A1)

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Q2) Legionella Levels

What is the significance of finding Legionella in my domestic water system? I am told the levels of infection are considered low.

A2)

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Q3) Legionella and Risk in disused buildings

What is the significance of the risk from Legionella in disused buildings?

A3)

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Q4) Legionella Tests

I currently have a wide cross section of commercial, industrial and local authority clients who contract us to manage their legionella control programmes. We carry out risk assessments, monitor temperatures and follow L8 guidelines as far as possible in managing their control programmes.

We also test for L. pn. on a regular basis and would like to firstly reassure our clients that across the board on domestic hot and cold water services a certain percentage of results come back positive. Obviously each one has to be investigated thoroughly to identify the reason behind the result. It would also be a very useful control statistic for ourselves to allow us to assess the effectiveness of our control measures compared to an industry average.

Do you have any figures on the average positive L.pn. sero group 1(or L. pn. species in general) as a percentage of samples submitted to laboratories in the UK?

A4)

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Q5) Microbiological Guidelines

Could you please supply me with the suggested microbiological guidelines for testing water samples?

I would like to know the guidelines for bacteria at 37 and 22 degrees Celsius for drinking water, cooling towers, showers, cold water storage tanks, cold water downs services and hot water services.

 

A5)

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Outdoor Systems, Rainwater Harvesting and Solar Panels

Q1) Water rides in Leisure parks

I am reviewing the water quality guidelines/standards that may, or are, to be applied to leisure park water rides, where there is an incidence of ride user contact with the water, typically through showering.

In association with the above what is the likelihood that dedicated water treatment would be required for what are typically enclosed water bodies?

A1)

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Q2) Golf course irrigation systems

I had a request from an agronomist to test for Lp on golf course irrigation systems and am seeking some help, guidance and or clarification on the same, as clearly this matter could be a minefield of practicalities. The system I have assessed thus far clearly presents a very high and significant risk, in summer operates above 20c,water is supplied to a 5kgal tank from a lake, is exposed to airborne contamination, tank has never been cleaned, during operation produces primary aerosol generation. Finally people more susceptible may contact said spray. It would not be practical or financially viable to clean/chlorinate the system every time a positive Lp result was confirmed, as the supply from the lake probably would be contaminated post cleaning process.Help !!

Any suggestions or help you can offer would be appreciated, for the record I have advised client to operate the system only between hours of 11pm/4.00am and when any members of staff are maintaining or checking equipment and spray, a full RPE PPE should be worn.

A2)

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Q3) Rain Water Harvesting

Is there any guidance available on Rain Water Harvesting for schools?

A3)

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Q4) Solar Heating

I have been looking at solar water heating systems recently. Most of them work through a heat exchange coil in a hot water cylinder. For compact systems there are two coils in the same cylinder. The solar coil being the lowest. This means that 5 months of the year at least a third of the cylinder is not heated to at least 50oC. Have you heard about any problems with them?

A4)

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Wet Scrubbers

Q1) Wet Scrubbers

Do you have any guidance on the control of Legionella in wet fume scrubbers used for the removal of odours?

A1)

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Refurbishment

Q1) Refurbishment of accommodation block

We are refurbishing a large soldier’s accommodation block, which has been empty for a number of months.

The refurbishment will include the stripping out of plumbing, heating, showers, tanks etc.

What tests do you feel are required to check for legionella prior to work commencing (if any) and what precautions should be taken during the work.

A1)

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