Legionnaires Disease - A reminder

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
27/12/2010 12:53

The thread below makes very interesting reading and those of you involved directly or even indirectly (Holidaying in property with Solar) be warned. Take steps to flush out the system before use if on holiday and do it without aerosolation. Those living in TRNC beware, keep that water moving. Flush water systems before use when the property has been empty for over a week. Need a method statement on this, email me. This goes for any owners in hot climates (CYPRUS SPAIN TURKEY etc). Those in the UK with Solar also take note.



If the solar industry ever claims to the public that there are no cases of Legionella linked to solar thermal, their claim is mistaken. In fact there was a major outbreak as long ago as 13 years ago in Antigua. There is also new evidence linking solar and Legionella from Turkey.



The claim that any risk is negligible is not supported by the evidence either.

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
27/12/2010 12:55

Indeed people may even be dying now, with the figure depending on what increased risk, if any, really attaches to solar thermal.



1/ Direct attribution of Legionella infection to solar water heating apparently exists.



Here is a case of Legionella which is apparently attributable to solar. I quote from:



http://www.q-net.net .au/~legion/Legionnaires_Disease_England_Wales_1996.htm

Tenakoutou



Joined: 27/07/2009
Posts: 4110

Message Posted:
27/12/2010 13:01

Interesting stuff, Vaughan - but will people take the warnings seriously, or just think 'it can't happen to me!' ?



It would be a very sound New Year's resolution to conform to the advice! - Thanks for this posting!

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
27/12/2010 13:09

Sorry for broken link:



http://www.q-net.net .au/~legion/Legionnaires_Disease_England_Wales_1996.htm

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
27/12/2010 13:11

Try again:



http://www.q-net.net .au/~legion/Legionnaires_Disease_England_Wales_1996.htm

nurseawful



Joined: 06/02/2009
Posts: 5934

Message Posted:
27/12/2010 13:12

Pathogenesis



Legionella live within amoebae in the natural environment.[6] Legionella species are the causative agent of the human Legionnaires' disease and the lesser form, Pontiac fever. Legionella transmission is via aerosols — the inhalation of mist droplets containing the bacteria. Common sources include cooling towers, swimming pools (especially in scandinavian countries and other countries such as Northern Ireland), domestic hot-water systems, fountains, and similar disseminators that tap into a public water supply. Natural sources of Legionella include freshwater ponds and creeks. Person-to-person transmission of Legionella has not been demonstrated.







The advise we were given when a patient in the ward was diagnosed with this was always to run the shower for at least 1 minute before getting in same with the washhand basins before brushing teeth. And we definately did not have solar panels at Law Hospital in Carluke Scotland.



Chris

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
27/12/2010 13:18

Chris,



You can drink water that is contaminated with Legionella, no problem. It is the inhalation of them that is dangerous. Showers are major sources as the water is sprayed into vapour and droplets which are inhaled. Many hospitals have wet cooling towers on the roof and these are extremely risky.

Legionella exists in stagnant water anywhere, not just in solar panels.

nurseawful



Joined: 06/02/2009
Posts: 5934

Message Posted:
27/12/2010 13:29

Vaughan,



Your link is still not working for me.



My point was that the tip about running the water for at least 1 minute I still use today and then in the early 90's when infection control told us about this we strictly adhered to this and never had another case in the hospital.



The danger seems to be from the stagnant water in the pipes rather than in the tanks / cooling towers etc. Hence the reason for running the water prior to getting in.



Chris

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
27/12/2010 14:58

There is a space just before ".au" which needs closing. I've tried but every time I copy and paste, the space comes back.



In some pipework systems there are what is known as dead-legs - for instance spur pipework that leads to taps in a rarely used spare bedroom en-suite. Although water is running through the building, water stagnates in these dead-legs. These taps need regular running through.

Water in water tanks contains Legionella - I guarantee you this - it's when it never gets used and replenished for long periods that the Legionella multiply in the warm/hot summer weather and they become a health hazard.

Wet, closed-loop cooling towers are paradise for Legionella.

I suspect that what went on behind the scenes in your hospital by your engineering staff accounted more for your success in controlling Legionella, than running the taps for a minute, but as they say at Tescos - "Every little helps".

colly


Joined: 31/07/2008
Posts: 297

Message Posted:
27/12/2010 23:36

quite right Vaughan,

for many many years dead legs with previously heated water that is cooling in hospitals and public buildings have been outlawed. It is something like a maximum of 1 metre from the point where the hotwater (at over 55 degrees so normally in excess of 60 degrees) is mixed with cold water to a temperature of between 43-45 degrees (to prevent scolding). For quite some time (in hospitals) showers have also had to have self draining valve to drain the water left in the riser pipe as well. Recently spray mixer taps in hospitals have also been avoided.

The old systems in the hospitals used a common mixer with long runs to shower heads and terminal points.



Now as for houses in the TRNC and other hot places the risk comes from the cold side as well as the hot cooling, with the amount of stored water we have flushing would not be practical as you may have to run some 10 tons or more water through, is there a treatment that can be added to the stored water?

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
28/12/2010 10:58

Hi colly,



Shower heads in public buildings are also superheated in autoclaves to kill of the Legionella.

The problem with LD is realizing that someone has died from it as, like bird flu, etc., it often kills people who are vulnerable with other conditions, the elderly for one, hence the name of the disease.



For domestic purposes, like villas in TRNC, draining, cleaning, disinfecting and flushing of tanks and pipework would be the norm. In the UK where water is cheaper(er) and plentiful (usually), this is OK but in TRNC it isn't and will become more unrealistic, particularly if it has to be done several times a year.

A far more practical method would be by silver/copper ionization, similar to the system we at Octopus Pools use in swimming pools, the Aligator.

http://www.aligator.co.uk

JohhnyLee


Joined: 25/04/2009
Posts: 2495

Message Posted:
28/12/2010 12:48

I reckon TRNC is probably a hot spot for legionaires, How many Air con machines are actually reguarly serviced ? or are they allowed to just keep running until there is a problem.



Also a very simple thing. If you do not intend to use a shower , (riser rail type not fixed head) for a few days. then leave it hanging down, to allow excess water to drain out, and as Nurse Awful quite rightly says let it run for a while before standing under it.



That little u bend that is created by the hose if you leave it in situ. is an ideal little pool of water to breed the disease. Then hey presto when you turn your shower , it will get you full on.



You need to be very careful, even hosepipes that are left outside, especially in hot weather.

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
28/12/2010 13:14

We should also take into account that Belediye water may not be as well "treated" as we might like it to be. Coming, as most of it does from well-water, if you wouldn't drink it because of what you suspect is in it, do you want to breath it in?

Allan


Joined: 28/12/2010
Posts: 40

Message Posted:
28/12/2010 16:23

Please send me a method statement for the flushing of a solar system



Many thanks

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
28/12/2010 16:35

I will post a method statement here rather than send it to you.

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
28/12/2010 16:42

Allan,



Just checked your profile and e-mail address.

Why do you need a method statement from me? You should have them coming out your ears.

Simonfrench


Joined: 27/12/2010
Posts: 2

Message Posted:
28/12/2010 22:01

Hi all,

I have sent a method statement to Vaughan for flushing. A point to be made here. If you stand in front of the shower when flushing without using a bag to minimise spray you may as well get in it to avoide wasting water! The point of flushing is to remove the Legionella assumed to have built up in the stagnant water. If you stand in the aerosols that you create you are likely to catch it. Not a good idea.



ANY flushing should be carried out using a bag as in Vaughan's method statement. Be especially careful in solar powered heating systems and make sure your hot tub is run correctly as well as this is supposed to be the second biggest killer from Legionella.



Hope this helps you all. (more info on http://www.whtlimited.com )



Simon French

Simonfrench


Joined: 27/12/2010
Posts: 2

Message Posted:
28/12/2010 22:02

Not many down services nowadays are disinfected in the UK due to maintaining correct temperatures but if they are it is best to use chlorine dioxide or Hydrogen/Silver mix. Vaughan is correct in stateing the obvious in that it is unlikely that you will have correct temperatures for many reasons one of which is the luxury of living in a lovely warm country and the fact many have over 24 hours storage of water and running on sun light for heating. Your temperatre regime is likely to fail. Ionisation is the best bet without using chemicals.

50% of the problem is stagnation. Got to keep the water moving. Next is dead ends (those with a cap on the end) in the UK we have no permitted length. They must be removed. Unused outlets, well that covered in the method statement Vaughan has.

Regards, Simon



PS Shame this site hasn't got a spell check!!! Got to watch what I type.

Allan


Joined: 28/12/2010
Posts: 40

Message Posted:
28/12/2010 22:02

Hi TRNC Vaughan



Yes I do, but its a always to speak to other people in the business certainly with knowledge of Legionella control, and to see other points of view, especially overseas in a place like NC. Where ambient temperatures are generally much higher than in the UK, hence the risk is increased. Are you based in the UK or NC?

Lp is a disease that occurs naturally in rivers and water courses and when it enters man made systems the colony count will rise due to nutrients such as iron oxide, bio-film, scale, etc, that's when it becomes a real danger.

Also I would like to move out to NC and do some work in this field perhaps later in the year.

Cheers

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
29/12/2010 10:59

Hi Allan,



Simon French and I have known each other for many years and we worked together as contractors for Westminster Health Care.

Water treatment is sometimes seen as a bit of a Black Art, as the problem is not visibly apparent and often the consequences of not carrying out any treatment are also not immediately apparent.

I have tried to promote water treatment in TRNC for some time with little effect.

I fear people are reluctant to pay for work they didn't know they needed, and that they can't see the results for. My own opinion is that water treatment is done in commercial premises for reasons of "CYA".

nurseawful



Joined: 06/02/2009
Posts: 5934

Message Posted:
29/12/2010 11:12

Does anyone actually know if there has been a reported case of Legionella here presently or the past before everyone starts to panic?



Chris

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
29/12/2010 11:43

No need to panic.

I don't know definitely whether there have or haven't. Without a proper diagnosis, who knows? Is TRNC any better at recognizing the problem than the UK? My guess would be that they might not be.

The problem with LD is it affects older people with existing conditions. My understanding is that these existing conditions become more serious combined with LD as does Bird Flu, etc., in older people.

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
29/12/2010 15:22

Allan,



I have sent you a method statement, as requested.

As water tanks are often inaccessible and/or the flushing of them would be wasteful, the best advice I have been given is low level disinfection by ionization, as mentioned previously.

http://www.aligator.com/hot-water-systems.php

Allan


Joined: 28/12/2010
Posts: 40

Message Posted:
29/12/2010 21:08

Hi all



Not sure I agree entirely with Simon, down services are disinfected where possible, that's where bio-film will form, due to various factors such as dead legs, blind ends, transfer of heat from heating or hot water pipes and ambient heat or merely lack of use. I do agree with the bag over the shower head when flushing discharged at low level to minimise the risk of contamination.

I use hydrogen peroxide with silver in the majority of cases especially in hotels, office blocks & health care where disruption is kept to a minimum. Huw-a-san is more effective in removal of bio-film than sodium hypochlorite as it has a slight effervescent reaction so breaks down the bio-film. A really good advantage is that you do not need to neutralise as with Hypochlorite where you may use sodium thio-sulphate to neutralise. This will sometimes create a slight acidic reaction from the calorifier (scale or sludge) resulting in discoloured water through the outlets.

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
30/12/2010 10:45

If anyone finds the above of any interest and wants to know how it may concern them, feel free to e-mail me at:

vaughan@sunnycyprus.net