FEATURE
The first factor is considered “universal”,
suggests that the bigger the chain, the help to dutyholders on water treatment and more likely it has people in position that hygiene, says in order for an individual to as low levels of legionella can enter water
will understand the legal requirements of develop Legionnaires’’ disease there must systems through the mains at very low, non-
implementing the Health and Safety at be a number of factors in place: hazardous levels, and in risk assessments
Work Act.” 1. A source of legionella bacteria it is “a given that there can be legionella
2. Conditions favourable for bacteria to in any water system at a low level”. The
WHAT IS LEGIONNAIRES DISEASE?
multiply to high levels
second factor is where operators of waters
Matt Morse, principal consultant at the 3. T
he creation of water aerosol (tiny droplets) systems have the most control over the
Dragonfly Water Consultancy, which 4. The presence of susceptible people risk of legionella growing. “Where water is
provides independent consultancy and
exposed to the aerosol
warm (20-45 centigrade), stagnant and has
nutrients for bacterial growth present (scale,
debris, algae, rust), legionella will rapidly
grow from low non-hazardous levels to
significant hazard levels,” says Morse.
“The third factor is most applicable
to applications like showers, cooling
towers or spa baths as fine spray is part
of the design,” he says. “Droplets or
aerosol with viable legionella bacteria can
survive in some conditions for hours and
travel significant distances.” The fourth
point is critical in assessing risk as some
individuals will be far more likely to develop
Legionnaires’ disease than others. As
mentioned by Koumi, Morse says smokers,
males, older people and people with
reduced immunity will be more susceptible.
DO HOTELS DEAL WITH OUTBREAKS
EFFECTIVELY?
“The answer to the question here is
typically no,” says Koumi. Containing the
disease lies on the enforcement notice
placed upon the hotel by the Health and
September 2018
www.hotelowner.co.uk
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