legionella management & control. legionellaceae legionella = aquatic bacteria naturally...

LEGIONELLA

MANAGEMENT & CONTROL

Nemco U T I L I T I E S

LEGIONELLACEAE


• Legionella = aquatic bacteria• Naturally widespread in the environment• 52 different species identified (April 15)• Half of which associated with human disease• In excess of 70 serogroups. • Legionella pneumophila

– 96% cases Legionnaires’ Disease– 3 subspecies and 16 serogroups– LP Serogroup 1 = 84% of cases Legionnaires’ Disease

WHERE IS IT ACQUIRED?


MORTALITY BY SETTING


CHAIN OF EVENTS


Bacteria present

Water stagnation

Nutrient source

Temperature range 20-50°C

Aerosol

Susceptible individual

BACTERIA


STAGNATION


NUTRIENTS


TEMPERATURE


AEROSOL


SUSCEPTIBLE PEOPLE


CASE HISTORY

• Flower Show - The Netherlands 1999• 242 Cases - 28 died • Source - Whirlpool Spa exhibit• Fed from hose • 2012 Stoke on Trent – 21 cases, 3 deaths

– JTF discount warehouse hot tub display – £200K out of court settlement– Prosecution being considered


HOME BIRTHING POOLS

• Jan 2014 – 1 month old baby in Texas dies • June 2014 – UK infant contracts Legionnaires’ disease • PHE Patient Safety Alert issued‘heated birthing pools, filled in advance of labour and where the temperature

is then maintained by use of a heater and pump, should not be used in the home setting’

• Legionnaires’ disease is very rare in childhood • 1 case in 0 to 9 year olds reported in England 1990 to 2011


PROSECUTIONS

• Aug 15 – Chromalloy UK £110,000 (£77,252)• Aug 15 – Coilcolor Newport £75,000 (28,393)• June 15 – Brighton & Sussex Hospital Trust £50,000 + £1.7M• Sept 13 - NHS Basildon £100,000 (£175,000) • Aug 13 - Mother Redcaps Care Home £40,000 • Reading Borough Council being prosecuted• Edinburgh Outbreak (2012) – decision not to prosecute


GUIDANCE

– ACOP L8 (4th edition) 2013– HSG274

Part 1 - cooling water systems.Part 2 - hot and cold water systemsPart 3 - other risk systems.


ACOP L8 REVISION

• Removal of technical guidance (HSG274)• Scope and application expanded - spa pools• Risk Assessment given ACOP status = greater authority• Removal of requirement to review RA every two years

“reviewed regularly or if there is a belief that it is no longer valid”

• Potential for “Responsible Person” to be an external party• Dissemination of information & discussion with employees• Review of control measures given ACOP status = greater authority • Responsibilities of manufacturers, importers, suppliers and

installers expanded = more onerous


LOW RISK SITES DEFINED

(a) in a small building without individuals especially ‘at risk’

(b) water usage is inevitable / sufficient to turn over entire system

(c) cold water is directly from a wholesome mains supply (no CWST)

(a) hot water is fed from instantaneous heaters or local volume (<15L)

water heaters (supplying outlets at 50 °C)

• the only outlets are toilets and wash hand basins (no showers).


HSG274 – Part 1


• Focuses management on ‘desired outcomes’• Inspection frequencies based on system type• Cleaning based on assessment rather than twice yearly - traffic light• Need for pack removal based on practicability & inspection

HSG274 – Part 2 (hot water)


• Hot water - stored at 60°C + and distributed so that it reaches 50°C within one minute at the outlets. (55°C in healthcare, residential or care home premises)

• Water Heaters - frequency of inspection based on SIZE and TYPE– Greater than 15L requires monitoring monthly (including its sentinel outlets)– Tanks supplying combination water heaters need to go on the annual tank

inspection regime.

HSG274 – Part 2 (hot water)


• Representative outlets - need only be monitored annually where sentinel outlets would not capture the temperature profile.

• Calorifiers – inspected on an annual basis or as dictated by the degree of fouling.

– Remove hatch or use a boroscope and clean by draining the vessel. – Where there is no inspection hatch, purge debris in the base of the

calorifier to a suitable drain.– Collect the initial flush from the base to inspect clarity, quantity of

debris, and temperature.

HSG274 – Part 2 (CWST)


• Whenever the building use pattern changes, a record of the total cold water consumption over a typical day should be established to confirm that there is reasonable flow through the tank and that water is not stagnating.

Water tank inspections and temperatures are now annual and ideally in summer.

HSG274 – Part 2 (TMVs)


• Risk assess whether the TMV fitting is required, and if not, remove • Be installed within 2 meters of the outlet• Where needed, inspect, clean, descale and disinfect any strainers or

filters associated with TMVs • On an annual basis the TMV will

need a failsafe test – if it fails then a service will be required

HSG274 – LANDLORDS


2.138 Landlords who provide residential accommodation…have a legal duty to ensure that the risk of exposure of tenants to legionella is properly assessed and controlled

2.143 Landlords should inform tenants of the potential risk of exposure to legionella and its consequences and advise on any actions arising from the findings of the risk assessment

LeafletsNotices / StickersNewslettersResident groups

HSG274 – HANDOVER


SIMPLE CONTROL MEASURES:

•flushing out the system before letting the property; •avoiding debris getting into the system (e.g. ensure the cold water tanks, where fitted, have a tight-fitting lid); •setting control parameters (e.g. setting the temperature of the calorifier to ensure water is stored at 60 °C); •making sure any redundant pipework identified is removed; •advising tenants to regularly clean and disinfect showerheads.

HSG274 – VOIDS


• Weekly flushing for short periods or part occupancy• Mothballing for full site / long term (chemical treatment)• Don’t forget new building commissioning!

HSG274 – Part 3


• ‘Other risk systems’• Monitoring ‘as indicated by risk assessment’

– the source of the water – likelihood of legionella contamination– the potential for microorganisms to grow– the potential for aerosol release– the likelihood of people being exposed to aerosols– The susceptibility of people being exposed

COMPETENT / RESPONSIBLE PERSON

• Managerially responsible for implementation & supervision• Sufficient authority, competence and knowledge of the

installation• Ensure all involved are trained and competent• Regular refresher training should be given and the

responsible person should have a clear understanding of their role

• Manage contractors and suppliers• Maintain records• Ensure regular reviews are carried out


legionella management & control. legionellaceae legionella = aquatic bacteria naturally...

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