Keeping on top of the legionella issue

Published:  02 July, 2014

maintenance, refurbishment, legionella, DHW, Legionnaires' Disease, Pontiac Fever, ACOP, Airmec
The threat of inspection — Andrew Steel.

Andrew Steel of Airmec reminds us that there are no magic wands when it comes to legionella control.

There’s no shortage of advice about legionella control — so why aren’t we all confident that we get it? If you understand fully the new guidance and latest regulations and have a clear idea of what inspectors are looking for — and how to avoid hefty intervention charges they can levy if they don’t like what they see — turn the page. The other 99.999% of you may wish to read on…

The nagging fear of failing in your duty of care is a powerful incentive to reach for the latest panacea. But before you sign up for the latest big idea, take time to ponder how you can best balance the law and code of practice guidance with your real-world budget.

The current frenzy of news about legionella control has surrounded last year’s publication by the Health & Safety Executive of the fourth edition of what is known as ‘ACOP L8’, the ‘Approved code of practice and guidance on regulations for the control of bacteria in water systems’. To be clear, an ACOP is not actually a law, but it does enjoy special legal status.

In a nutshell, the latest, fourth edition of the ACOP contains revisions intended to simplify and clarify the text. In practice the main changes centered on removing the technical guidance, which is now published separately as HSG 274. It is only upon reading the fine print of HSG 274, Parts 1 to 3 dealing, respectively, with evaporative cooling systems, hot- and cold-water systems and other systems, that you may find that some of the intended clarity could be lost on you.

However, the way to achieve certainty and clarity is probably not to throw money at what might not be a problem after all. It may be far better to take an holistic view of the systems in your premises, review your schematics and risk assessments — and then tailor preventive measures to what you can afford and have the resources to do properly. There’s no point in fitting devices if you are unaware of their limitations. Look, for instance, at the trend towards UV sterilisation of taps and shower heads, which might seem, at first glance, to be a panacea — indeed they are a good innovation. Such devices are, however, only part of a potential solution when combined with a robust water-management plan. There may be alternatives that are less capital intensive but just as effective. Can you afford to manage that risk as well as to service the capital cost and maintenance of the units? If so, all well and good, if not, perhaps a more pragmatic approach is called for?

There is, at the end of the day no magic wand. Risk management always starts with a comprehensive risk assessment, which should be treated as a live working document and not something that can be filed away for two years.

It might be thought that every responsible organisation already has such a live risk assessment, but surprisingly few do. There is a lot of work out there that is either outdated or just plain inaccurate. Yet the cost of dealing with a positive laboratory analysis or even an outbreak rises dramatically, as does the cost of business disruption, if there is not a good risk assessment to work from.

Let’s be clear, this is not a criticism on the HSE’s technical guidance; producing it is a massive achievement, but there are bound to be teething troubles as it beds in.

maintenance, refurbishment, legionella, DHW, Legionnaires' Disease, Pontiac Fever, ACOP, Airmec
No shortage of advice about legionella control.

There is, however, no leeway to stand back and watch that happen because the inspectors can come knocking any day. We’ve been aware, for instance, of a Health & Safety executive focus on evaporative cooling towers in recent months — after all a third of cases Legionnaires’ Disease and Pontiac fever are attributed to cooling towers and poor risk management.

There have been some significant ‘intervention fees’ slapped on firms whose risk assessments do not meet requirements that only came into force in December 2013, so forget the idea of two-yearly risk assessment that we are all rather used to. If it was undertaken before last Christmas, it’s probably wrong!

The HSG guidance clearly states that assessment of risk is an ongoing process and not merely a paper exercise; now they are showing that they really mean it! No matter how good your risk assessment, if you thought it could sit on the shelf for two years before review, think again.

While the use of cooling towers is declining as other more efficient heat exchangers gain in popularity, legionella prevention in hot and cold water should remain high on anyone’s agenda. The market has come up with no end of solutions, but none of them offer a complete answer.

Inspectors rightly look for proof that you understand the risks in your premises and have a plan to deal with them — and they want to see documented proof that you carry out that plan.

Whether that plan involves fitting brand new hardware or flushing old taps regularly or, more likely, a combination of both is up to you. Just be sure that you have enough knowledge of your own systems to make the right management choices and never, ever take your eye off the ball. There, quite simple, are no fit-and-forget solutions to be had.

Andrew Steel is managing director of Airmec.

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