Legionnaire's Disease; 10 Things An Employer Should Know

Richard Mills, The RedCat Partnership Ltd

Legionnaire’s Disease; The Top 10 Things You Need to Know
The outbreak of Legionnaire’s Disease in Edinburgh has caught media headlines; one fatality, 88 in hospital (14 in Intensive Care), three Improvement Notices from HSE. It’s been 10 years since something similar has happened (Barrow-in-Furness; 180 cases, 7 fatalities, one manslaughter conviction). As it can be a work-related health and safety hazard, we thought it about time to dust off the key facts for you.

1. What is it? The illness is caused by a bacterium, Legionella pneumophila, which is very common in the environment.

2. How Do I Catch It? The germ likes water systems. Once inside these systems, in the right conditions, it will multiply. The contaminated water then needs to be sprayed into a mist, vapour or aerosol. The victim breathes in the contaminated aerosol, introducing the germ to the nice, warm, moist lungs. It then causes illness.

3. How Bad Is It? As it’s in the lungs, it causes a form of pneumonia. At one end of the scale, it can be a mild respiratory illness (normally called Pontiac Fever), up to fatal. Fatality rate varies, maximum 30% in extreme cases

4. How Bad Is It (2)? As always there are more vulnerable groups; infants, the elderly, people already ill, and (interestingly but not surprisingly) smokers.

5. Which organisations need to take heed? “At risk” water systems are (no surprise) those that produce water vapour or mist. Examples we’ve looked at include;

  • Showers are the most common we come across; hotels, sports clubs, etc but don’t forget emergency showers.
  • Spa baths. Those in swimming pools tend to be well managed, but in hotels things like “Jacuzzi” baths a can be overlooked (think of all that dirty water sitting in the bottom of the pump systems....)
  • Fire sprinkler and wet riser systems
  • Lathe and machine tools, where a cooling liquid is jetted onto work-pieces or cutting blades
  • Horticultural misting systems
  • Car washes
  • Indoor fountains/water features
  • Large air conditioning or industrial cooling systems (such as the three in Edinburgh that have so far been served with Improvement Notices). These are larger systems that include an “evaporative condenser” like power station cooling towers. These are actually notifiable to the HSE or Local Council, as they give off large clouds of water vapour from systems that can readily be colonised by the bacterium.

6. What Do I Need To Do If I Have An “At Risk” System Under My Control? A risk assessment (no surprise there), and, if controls need to be put into place, then these need to be part of a management system. These both need to be recorded if you have 5 or more employees (management arrangements usually in your Safety Policy).

7. What goes into a risk assessment?
a. How likely is the contamination of the system? Have a guess from the picture below...)
b. How likely is it that the bacteria will multiply to dangerous levels? This in turn includes looking at water temperatures (highly important; the bacteria prefer water at 20-45OC), flow rates (stagnant water or little used outlets), shelter for the bacteria (scale, rust, poor materials used in plumbing, etc) and food for the bacteria (things like slime inside water tanks)
c. Likelihood of a mist/vapour being formed (a certainty with all of the systems mentioned above)
d. Likelihood on someone breathing the vapour, and if any of those people are more vulnerable. How many people, how often, distance from the source of vapour, etc.
What do you mean by “management arrangements”? There are some specifics in HSE Codes of Practice, including; nominating someone to take responsibility for putting control measures into place having a schematic (diagram) of the water system the water system’s operating settings, etc (a “Normal Operating Procedure”). This might include thermostat settings, for example. Staff awareness training, especially for anyone managing the water systems, but could also include cleaners.
Precautions might include things like how to make sure little used water outlets are managed (e.g. hotel showers that haven’t been used over winter).
These arrangements will also include monitoring, as one of the most important control measures is temperature control. Who is going to measure water temperatures, where, how often and how? Where and how should this be recorded? What should they do if water is found to be between 20 and 45OC?

8. Are there any local examples of Legionnaire’s Disease? In my former life as a H&S inspector I investigated one fatal outbreak in King’s Lynn. As a consultant, one tourism client was implicated in a fatality (as the victim had stayed with them), but having a decent risk assessment (plus clearly implemented improvements) and management plan eliminated this business from the investigation. The business could show that the water system had been properly assessed, and that controls/monitoring were in place (through documented procedures) and robust.

9. What Should I Do Now? Decide if you have an “at risk” water system. Make sure you have a decent risk assessment that looks at the factors in 7 above. If you have an assessment, has it been reviewed regularly (e.g. have water systems been changed)? Does your safety policy include the necessary management arrangements?

10. Some examples of how not to do it....



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