Pipes + taps + heater + water = risk of LD.

Starting point for that level of risk is pretty low though so long as the following assumptions are met:

- Mains water

- Incoming water below 20C, hot water supplied above 50C

- Daily use of water

That is the nature of the assessment/approach you could take in this scenario i.e. an assumed level of low risk with a means to test those assumptions and react accordingly to local context/variation.

Originally Posted by: Xavier123

Pipes + taps + heater + water = risk of LD.

Starting point for that level of risk is pretty low though so long as the following assumptions are met:

- Mains water

- Incoming water below 20C, hot water supplied above 50C

- Daily use of water

That is the nature of the assessment/approach you could take in this scenario i.e. an assumed level of low risk with a means to test those assumptions and react accordingly to local context/variation.

Many thanks for your reply and advice Xavier123. What about the lack of potential for any water to become aerosolised and therefore be inhaled to a persons lungs? 

^  What he said. ;) ^

Aerosols that can be inhaled deeply into the lungs are measured in microns. So we're not talking water droplets. Although frankly anywhere that a water surface is broken will produce them albeit in varying levels of quantity, size and velocity.

You don't often get outbreaks from them but I've investigated several cases of LD where the most likely source was a tap.

Morning Wayne,

You have identified a tricky problem for a lot of people engaged in smaller scale construction projects using small or mobile welfare units that use stored water supplies.

Yes the Legionella ACOP (via COSHH Regs) would apply.  Yes there is quite often a risk (certainly aerosol potential, certainly the potential for temperature excursions)

But how are these solved?  Lets not forget that the term risk assessment is often bandied about as a solution but risk assessment is only a process and doesn't magic up solutions in and of itself (despite the number of people whose answer to any tricky issue is "your risk assessment will tell you", which is my professional pet hate). 

So you hire in a top of the range self-contained mobile welfare unit (I happened to be sitting in a brand new 6 person 'Groundhog' type unit of very good quality from a national well known and professional hire company only yesterday). 

When the unit is selected you identify in your Legionella risk asessment that the water supply is static and stored in the main welfare area that is subject to the integrated heating system in the winter (may possibly get over 20c) or subject to being inside a metal box in the summer (probably get above 20c on hot days).  Then you have the requirement for 'warm' water from CDM and the integrated water heaters are not quite instantaneous and there is a small resevoir in each unit feeding a warm supply unlikely to exceed 50c.

So what do you do?  You can't modify the on-hire and award winning welfare unit.  You can't store the water outside as its integrated and in the summer it will also get warm outside.  You have no mains supply hook up.

You have identified your risk but can do nothing about it.  Your auditor 'needs' his bit of paper, that actually does nothing for you other than ticking a box on his audit proforma.

So what do you do?

Perhaps I've been doing this too long and have developed a level of cycisism or maybe I've been doing it long enough to understand the big picture of what we should all be trying to achieve with 'reasonably practicable' and 'record significant findings'.  It neither benefits H&S, our profession or more importantly the people in the front line of risk to create long and weighty documents that achieve little or nothing other than the creation of a document.  Absolutely, I am a staunch advocate of documents that record significant findings and provide users with valid evidence of compliance, however documents that meet a theoretical rather than practical need actually undermines the vital information communicated to users.

What I would do is engage the auditor and explain that yes there is a risk, however it is not significant therefore no record of the risk assessment 'needs' recording and everything is in place (thanks unit designers) to manage those risks 'as far as is resonably practicable'.  Answer the non-compliance formally in the same way if required.

Whats the alternative?  The good old days of urinating in the corner and popping off to the pub for anything more.  No, lets keep using these very good units that MAY have minor residual legionella risk.

Lets leave good, thourough L8 risk assessments for their real purpose, complex water systems, vulnerable persons, heated water systems in public areas (hot tub showrooms and water features in shopping sentres etc) and most importantly evaporative cooling systems.

(Crikey that was a long rant wasn't it ;))

I have to say I don't agree with Holliday - L8 does not contain the get out clause of "record the significant findings"  it is an absolute requirement.  Simple systems do not require a complex risk assessment or a very in depth and complex management plan but they still do need a risk assessment and a plan.  2 sheets of A4 should cover it nicely - job done.  Not onerous, not difficult but it is needed so do it!

As a fairly competent legionella risk assessor I would suggest that leaving a Groundhog unit be in the knowledge that you had inadequate temperature control and turnover could be non-compliant - albeit I respect that the risks themselves remain low in the grand scheme of things. This doesn't need complex or specialist assessment - if it can't achieve the standards recommended in HSG274 Part 2 then no massive leap of expertise is required. I'm not too fussed how many awards the unit has won and neither is legionella. There are further actions that can be taken in such situations.

With regard to documents - also can't stand them where unneccesary and detest overproduction. However a written scheme of control is nonetheless required (paragraph 58) where a risk is foreseeable. There are control measures in place - temperature, volume, turnover, nature of user etc. - and they form the basis on which assumptions of low risk are made. The asssessment is reviewed when the scheme is shown to no longer be effective. In very practical terms HSG274 suggests this could be 6 monthly temp check on the water/turnover.

The scheme could (and should) be as short as a paragraph in order to deal with the logistics of describing and testing this i.e. reviewing the assessment and conveniently double up as a record of that low risk assessment at the same time.

Good Afternoon All

Thank you to all who have contributed to date. The comments are assisting me in determining the appropriate response to the non conformance raised during our recent IMS audit. I would like to address, provide clarity on, some of the points i have read so far in the thread.

The hot wash toilet is a self contained electrical powered unit which is serviced and replenished by the supplier on a 7 day rota (the calc used =<7 persons working a 40hr week). 

Taps in welfare unit used as required according to site conditions etc. but used daily as a minimum.

Water supply to Groundhog may be by a tested mains connection, if the substation has an operational supply in place, or as Holliday42333 suggested a portable supply (IBC or similar approved water container). Some operatives still prefer to bring their own bottled water in to use even though all sites are set up as per CDM welfare requirements.

As Hsqaured4 suggested, i dont feel that we 'have been caught out' in any way and my rationale, which is exercised daily in my SHEQ role, is just fine. Im positive it wont take 2 sheets of A4 to explain it.

Thank you to Holliday42333 for taking the time to explain the issues with this type of small CDM construction site. My discussion with the IMS auditor was not to get into a disagreement with him about the technicality of a non conformance in relation to a lack of documented risk assessment but, as Holliday42333 points out, the expectation that this potential risk requires a comprehensive risk assessment carried out with a detailed water management plan.

During the onsite conversation between the auditor and I, it was evident that the auditors technical knowledge of Legionnaires was limited as he suggested, IMO, some extreme examples of where this type of risk may occur. All of these examples had crucial factors missing for the risk potential of Legionnaires to be anything else but insignificant. (i.e. lack of correct environment, temperature etc.)

I talked through how our small CDM sites are set up, and have been continuously improved, for well in excess of the past decade. There has been zero incidences of reported ill health from our own operatives or contractors that we supervise as Principal Contractor. I also talked through our standard 5x5 risk matrix and without writing the present control measures down we are already at a starting point of Low Risk. 

I agree with Dazzling Puddock that flushing is good practice and we are assured by our quality checked supplier that all Groundhogs are provided in a safe condition for use as described.

3 months hire time for these units is a maximum for our organisation and all quality documentation is supplied on delivery to site. This is checked and entered into our site CDM file.

In summary, i feel that considering we work in substations consisting of electrical equipment upto and including 400kV, (this extremely high risk environment and supporting docs were not interrogated by the auditor for reasons known only to himself) that i have spent an amount of valuable time during a 2 day audit discussing and dealing with a non conformance that is of low risk or worse, insignificant, to our operations.

Apologies for the length of this post but i hope it gives a clearer picture of events.

I'm sorry if you don't agree with me but L8 is very clear - ALL systems in the workplace require a risk assessment but not all require a comprehensive management plan.  For your very simple systems all that is required is a short risk assessment and I see no reason why given what you have said that it couldn't be done on 2 sheets of A4.  All you need to do is write up everything you have expounded on here as a risk assessment.  You could have written your risk assessment half a dozen times in the time you have taken on here to argue why you don't want to do one.  Just pull your finger out and do it!!  I'm not disputing that the risk is very low but you can't use that as an arguement with regards to L8 - there is no significant risk get out clause in L8.