The control of legionella The control of legionella Bacteria in Water Bacteria in Water

SystemsSystems

June 2013 – Bakery Water June 2013 – Bakery Water SystemsSystems

IT HAS LEGAL STATUSIT HAS LEGAL STATUS

This code has been approved by the health and safety This code has been approved by the health and safety commission with the consent of the secretary of state. It commission with the consent of the secretary of state. It gives practical advice on how to comply with the law. If gives practical advice on how to comply with the law. If you follow the advice you will be doing enough to comply you follow the advice you will be doing enough to comply with the law in respect of those specific matters on which with the law in respect of those specific matters on which the code gives advice. You may use alternative methods the code gives advice. You may use alternative methods to those set out in order to comply with the law.to those set out in order to comply with the law.However the code has a special legal status. If you are However the code has a special legal status. If you are prosecuted for breach of health and safety law, and it is prosecuted for breach of health and safety law, and it is proved that you did not follow the relevant provisions of proved that you did not follow the relevant provisions of the code, you will need to show that you have complied the code, you will need to show that you have complied with the law in some other way or a court will find you at with the law in some other way or a court will find you at faultfault..

WHERE TO STARTWHERE TO START

Risk AssessmentRisk Assessment

Schematic drawings of water systemsSchematic drawings of water systems

Written Scheme of actions required to both Written Scheme of actions required to both monitor and control bacteria in water monitor and control bacteria in water systemssystems

RISK AREASRISK AREAS

Any water system that has the potential to Any water system that has the potential to support support legionella bacterial growth, and growth, and the means to create water droplets that the means to create water droplets that can be inhaled.can be inhaled.

LEGIONELLA GROWTHLEGIONELLA GROWTH

Food – bacteria, corrosion deposits, Food – bacteria, corrosion deposits, contaminants, general sludge and debriscontaminants, general sludge and debris

Temperature – 20Temperature – 20ºCºC to 45 to 45ºCºC

Habitat – scale, tanks, dead legs, stagnant Habitat – scale, tanks, dead legs, stagnant water areas, biofilmwater areas, biofilm

LEGIONNAIRES DISEASELEGIONNAIRES DISEASE

Approximately 40 species of Approximately 40 species of legionella bacteria exist. exist. Legionella Pneumophila Serogroup 1 is most Legionella Pneumophila Serogroup 1 is most commonly causes 82% of all known cases of commonly causes 82% of all known cases of legionellosis.legionellosis.12% of reported cases are fatal.12% of reported cases are fatal.Incubation takes 2-10 daysIncubation takes 2-10 daysMost at risk are males aged 45 who are Most at risk are males aged 45 who are alcoholics and smoke and have diabetes, cancer alcoholics and smoke and have diabetes, cancer and chronic respiratory or kidney disease. i.e. and chronic respiratory or kidney disease. i.e. the immunosuppressed.the immunosuppressed.

HIGH RISK WATER SYSTEMSHIGH RISK WATER SYSTEMS

Cooling towers / evaporative condensersCooling towers / evaporative condensers

Basket washers / tub washesBasket washers / tub washes

Bread coolersBread coolers

Pressure washersPressure washers

Hot and cold water domestic systemsHot and cold water domestic systems

Lorry washersLorry washers

Splitters / sprayersSplitters / sprayers

COOLING COOLING TOWERS/CONDENSERSTOWERS/CONDENSERS

BASKET WASHERSBASKET WASHERS

BREADCOOLERSBREADCOOLERS

HOT AND COLD DOMESTICSHOT AND COLD DOMESTICS

Written schemeWritten scheme

Details all required tests, actions, Details all required tests, actions, monitoring required to minimise the growth monitoring required to minimise the growth and dissemination of legionella bacteriaand dissemination of legionella bacteria

Defines what tests are to be done, by Defines what tests are to be done, by whom and at what frequency.whom and at what frequency.

TYPICAL WRITTEN SCHEMETYPICAL WRITTEN SCHEME - - DAILYDAILY

Check systems are operating correctlyCheck systems are operating correctly

Check Check water treatment chemicals are stocked and dosing

Report any unusual conditions Report any unusual conditions immediatelyimmediately

All of the above must be loggedAll of the above must be logged

WEEKLY CHECKSWEEKLY CHECKS

Flush little used outlets, dead legs etc.Flush little used outlets, dead legs etc.

Test cooling towersTest cooling towers

Test breadcoolersTest breadcoolers

Test basket washersTest basket washers

Clean breadcoolers, basket washers, Clean breadcoolers, basket washers, splitters, tub washers etc.splitters, tub washers etc.

DIP SLIDE RESULTSDIP SLIDE RESULTS

TOWER TESTS - WEEKLYTOWER TESTS - WEEKLY

ConductivityConductivity

pHpH

Free HalogenFree Halogen

TVCTVC

1000-20001000-2000

6.5 - 9.06.5 - 9.0

0.5 - 3.00.5 - 3.0

<10<1055

BREAD COOLER TESTS - WEEKLYBREAD COOLER TESTS - WEEKLY

Conductivity / concentration factor to Conductivity / concentration factor to demonstrate chemical retention timedemonstrate chemical retention time

pH to ensure correct environment for pH to ensure correct environment for chemical activitychemical activity

Visual inspections for breadcrumb, mould Visual inspections for breadcrumb, mould etc.etc.

Dip slide for TVC and mouldDip slide for TVC and mould

Chemical tests where applicable.Chemical tests where applicable.

BASKET / TRAY / RACK BASKET / TRAY / RACK WASHERS - WEEKLYWASHERS - WEEKLY

Temperature in wash & rinse sectionsTemperature in wash & rinse sections

pH for chemical in wash tankpH for chemical in wash tank

Checks on pumps, drains, air blowers, Checks on pumps, drains, air blowers, tanks etc.tanks etc.

MONTHLYMONTHLY

TemperaturesTemperatures

Full Water analysis of towers, Full Water analysis of towers, breadcoolers, lorry washes etc by water breadcoolers, lorry washes etc by water treatment service providertreatment service provider

Bacterial analysis of varied water systems Bacterial analysis of varied water systems and random sample points.and random sample points.

Legionella tests of systems that are out of Legionella tests of systems that are out of specification and a cause for concernspecification and a cause for concern

QUARTERLYQUARTERLY

Legionella sampling of cooling towers sampling of cooling towers

Descale and sterilisation of showerheads Descale and sterilisation of showerheads and spray nozzles and spray nozzles

Bacterial analysis of incoming water Bacterial analysis of incoming water supplies to key water systems like cooling supplies to key water systems like cooling towers.towers.

Formal review of water treatment records, Formal review of water treatment records, results, checks and any corrective actionsresults, checks and any corrective actions

Bi-ANNUALBi-ANNUAL

Sterilisation of softener resin bedsSterilisation of softener resin beds

Cooling tower cleansCooling tower cleans

Full chemical deep cleans of breadcoolersFull chemical deep cleans of breadcoolers

Temperature of incoming water supplies to Temperature of incoming water supplies to water storage tanks and buildings.water storage tanks and buildings.

YEARLYYEARLY

Inspection of water storage tanksInspection of water storage tanks

Blowdown and inspection of hot water Blowdown and inspection of hot water calorifierscalorifiers

Review of written scheme, training Review of written scheme, training records, lines of communicationrecords, lines of communication

Re-issue of code of conduct, contractors Re-issue of code of conduct, contractors safe at work cert, risk assessments and safe at work cert, risk assessments and method statements for activities on sitemethod statements for activities on site

TWO YEARLYTWO YEARLY

Review of risk assessment.Review of risk assessment.

This is not limited to every 2 years. If any This is not limited to every 2 years. If any changes to a system occur, a review of the changes to a system occur, a review of the risk to that system must be completed risk to that system must be completed immediately.immediately.

FOR FURTHER FOR FURTHER INFORMATIONINFORMATION

Contact AKVO LtdContact AKVO Ltd

Tel 0844 244 8726Tel 0844 244 8726

Or visit Or visit www.akvo.co.uk