ADVICE & OPINION
COMPLIANCE
LEGIONELLA: THE HIDDEN RISK
Eric Myers, Senior Industry Technical Consultant at Ecolab and a Waterborne
Pathogen Risk Reduction Strategist, on how the unique circumstances for
buildings that wouldn’t typically experience months-long shutdown may have
increased the risk of legionella and how to mitigate that risk https://en-uk.ecolab.com
Many businesses around the world have
had little to no occupancy during the
COVID-19 pandemic. Low occupancy could
potentially become a public health threat within
commercial o ice buildings that have remained
dormant. Many facility managers could be caught
unprepared if these risks are not appropriately
examined and addressed as businesses begin
return-to-o ice plans.
One o en over-looked risk is Legionella. As
buildings experienced reduced occupancy during
the last two years, water flow within buildings
has also decreased, which can increase the risk
of a Legionella growth and spread. Legionella, a
waterborne pathogen, can grow in stagnant water
systems. When inhaled as an aerosol or water mist,
it can have severe health risks - causing symptoms
similar to pneumonia, high rates of hospitalisation
and increased risk to the immunocompromised.
According to the CDC, one out of 10 Legionnaires’
disease cases are fatal, making it a critical risk for
facility managers to address.
WATER SAFETY MANAGEMENT PLANS
While many facilities have water safety management
plans already in place, the last two years have
presented a unique situation. Factors such as
water stagnation, insu icient disinfectant and poor
temperature controls can lead to conditions that
allow the growth and spread of Legionella from
common water access points like water fountains,
14 MAY 2022
sinks and showers. Cases are projected to continue
increasing with urbanisation, ageing populations,
and water systems. Not only can Legionella cause
severe health risks, the World Health Organisation
estimates an outbreak can cost an average of $10.6
million in tangible expenses like remediation and
lost productivity, plus so costs like damage to brand
reputation.
Return-to-o ice plans should consider and address
Legionella risks before building occupancy increases.
The five points outlined below can help identify and
mitigate the risk of Legionella in your building.
Review or develop a water management plan
- Taking a water system inventory, developing
process flow diagrams, and assessing risk
It is important to create a written plan for the water
systems first. The plan should include identification
of at-risk water systems, specification of proper
operation parameters and control measures, and
guidelines for maintenance. Technology such as 3D
TRASAR™ Cooling Water Technology gives facility
managers the platform to measure and monitor
risks. Further, Water Safety Intelligence , powered
by ECOLAB3D, enhances traditional water risk
management by providing 24 / 7 visibility to help
identify and mitigate potential risks.
Give consideration for long-term supplemental
disinfection - Choosing the optimal solution
Complex water systems, lack of potable water
In association with
disinfectant residuals and ideal temperatures
for the growth of Legionella may drive the need
for supplemental disinfection. Supplemental
disinfection remains among the best strategies to
limit microbial growth in a building’s domestic water
system. Domestic cold and hot water systems can
provide ideal conditions for pathogen growth, and
system complexities can be challenging to address.
However, current technology generates chlorine
dioxide or chlorine onsite to help address these
unique challenges and support proper control of the
disinfectant application.
Point-of-use water filters can be a short-term fix
Point-of-use water filters can be used in an emergency
to allow time to implement remedial action or as
a long-term control strategy for high-risk of critical
areas. These filters are commonly used in showers, ice
machines or other water fixtures.
Implement short-term remediation procedures
Short-term remediation procedures can be
performed on many types of water systems
including cooling towers, potable water systems,
decorative water features and potable water storage
tanks. Remediation involves not only cleaning and
chemical disinfection, but also providing the proper
documentation to verify the process was completed.
Seek the help of an experienced and competent
service provider to ensure proper procedures are
safely followed.
Legionella monitoring using culture and
molecular testing
Molecular-based tests for Legionella identify the
presence of Legionella DNA in water and provide
results in genomic units within one to four-days.
Monthly test results can show if Legionella bacteria
are increasing and can complement quarterly
Legionella culture testing to ensure the e ectiveness
of a water management plan. The molecular-based
test can also be used to confirm the e ectiveness of
remedial cleaning and disinfection procedures.
With varying occupancies and operational changes,
the conditions facing facility managers are unlike any
we have experienced before. It is now more important
than ever for facility managers to view water safety as
a continuous process of assessing, acting, analysing,
adjusting, and repeating. Identifying water risks is an
essential step before o ice employees can confidently
return to a new version of business-as-usual.
/en-uk.ecolab.com
