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Mick Noonan  
#1 Posted : 01 August 2013 15:20:30(UTC)
Rank: Forum user
Mick Noonan

Hello All, I'm looking for some specific information here. Is there a connection between these two? Are there any legionella experts out there? Should we be testing our sprinkler system water for this? Does anyone out there actually test their sprinkler water for this or have additives to prevent this (does such a thing exists)? Lots of questions, I know. Over to you. Mick
phargreaves04  
#2 Posted : 01 August 2013 15:44:27(UTC)
Rank: Forum user
phargreaves04

I would have thought this would be pretty negligible as they are normally closed systems. Also the water would be below 20 degrees where Legionella is dormant. If spinlers come on hopefully people are getting or are out the building.
kevkel  
#3 Posted : 01 August 2013 15:47:16(UTC)
Rank: Super forum user
kevkel

Hi Mick, Not a legionella expert by any means but yes as a stored water system (by default) they do pose a risk of legionella as do hose reels. They can be flushed out using a chlorine solution and of course water sampling should be completed. There are some organisations who can do this work for you if you do an internet search.
Ron Hunter  
#4 Posted : 01 August 2013 15:57:38(UTC)
Rank: Super forum user
Ron Hunter

I understand that there is a collective acceptance that whilst there is a risk if (and only if) the sprinklers are activated, this is far outweighed by the resultant benefit of extinguishing a fire.
David Bannister  
#5 Posted : 01 August 2013 16:11:54(UTC)
Rank: Super forum user
David Bannister

Water in sprinkler distribution pipework will be an excellent medium for legionella growth: high-ish temperatures at roof level, oxidised steel pipework, static water. Sprinkler engineers should take suitable precautions when draining down a system to avoid creation of and exposure to aerosols. There is the very small risk of exposure when a forgetful FLT driver brings down a pipe or bangs a head in the racks. If there is sufficient heat to cause a sprinkler head to activate nobody should be left in the area anyway and as Ron says, it's a balance of risk in favour of sprinklers. So far as the storage tank is concerned, UK summers are not likely to raise the temperature above 20 degrees and wasting that large volume of water to do a clean and swill with chlorine is just not reasonably practicable. I am not aware of any outbreak traced back to exposure to sprinkler water. As an aside, fork lift drivers only tend to crack a pipe once. They either get sacked or realise that it's not good practice!
Mick Noonan  
#6 Posted : 01 August 2013 16:20:13(UTC)
Rank: Forum user
Mick Noonan

Clearly it's the lesser of two evils when it comes to a fire situation, however, my research (such as it is) tells me that the risk is there (however small). My concern is more focused on those that work with sprinkler systems and are therefore a more high risk group due to the nature of their work. The more you think about it, however, the more it's clear that we are all at risk at any moment. Not to be alarmist but you could extend this arguement to people who work with air conditioning systems or plumbers who specialise in hot water systems, or Legionnaires (apparently). Jokes aside, the extension also runs to excavations & muddy puddles. Now we really are into the realm of conkers bonkers. Mick
Lisa Boulton  
#7 Posted : 02 August 2013 16:17:40(UTC)
Rank: Forum user
Lisa Boulton

There are different types of sprinklers, wet systems that hold water continuously in the system and dry systems that hold the water back under pressure, so it will also depend on the type of sprinkler system that you have. As previously stated during a fire the benefits of a sprinkler far outweigh the risk of legionella infection, but you need to consider maintenance and testing and abnormal operations or breakdown of the unit and whether the risk of infection would be an issue then. Not particularly helpful but what you decide for your scheme of control will be determined by your risk assessment. Regards Lisa B
jarsmith83  
#8 Posted : 03 August 2013 11:45:01(UTC)
Rank: Super forum user
jarsmith83

Lisa Boulton wrote:
There are different types of sprinklers, wet systems that hold water continuously in the system and dry systems that hold the water back under pressure, so it will also depend on the type of sprinkler system that you have. As previously stated during a fire the benefits of a sprinkler far outweigh the risk of legionella infection, but you need to consider maintenance and testing and abnormal operations or breakdown of the unit and whether the risk of infection would be an issue then. Not particularly helpful but what you decide for your scheme of control will be determined by your risk assessment. Regards Lisa B
Good advice from Lisa. Sprinkler systems are low risk and depending on the system would normally be fitted with back check valves or air gaps to minimise contamination to the rest of the system as per bs en 806-5 2012. As already mentioned the greater good of the system outweighs the risk and the system has been installed for emergency situations only. The system is not regarding as a little used outlet so does not require weekly flushings. Page 58 of L8 details the 'control measures' required and simply states "minimise aerosol release during maintenance/blow downs". You would need to then refer to the maintenance regime recommended by the installer and maintainer of the system and ensure they have RAMS for this process. Accidental release is not regarded as high risk, as this is not the original intended design of the installation. Similar to unwanted accidental activation of fire alarm systems, the accidental incident should be investigated and remedial actions implemented and recorded to ensure or minimise the reoccurrence. If tank fed then the tank would require 6 monthly and 12 monthly checks, this would be to check temps as per L8 and to ensure condition & compliance with BS6700 (at least I think that is the standard but don't have this to hand as its the weekend :-), it's basically the specification for how tanks should be installed. Just finished the BS23 course and this was discussed in length. Hope this info helps.
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