New Rules on Legionella Prevention
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Transcript of New Rules on Legionella Prevention
New Rules on Legionella New Rules on Legionella PreventionPrevention
N. BangertN. BangertTS Workshop 2005, ArchampsTS Workshop 2005, Archamps
Table of ContentsTable of Contents
• Diseases caused by LegionellaDiseases caused by Legionella• Living environment / Installations with riskLiving environment / Installations with risk• Cooling towers at CERNCooling towers at CERN
– Analysis and limitsAnalysis and limits– Preventive chemical treatmentPreventive chemical treatment– Corrective chemical treatmentCorrective chemical treatment– Annual preventive maintenanceAnnual preventive maintenance– Personnel protectionPersonnel protection– Conception and Follow up of Cooling TowersConception and Follow up of Cooling Towers
• ConclusionsConclusions
• Legionnaires’ DiseaseLegionnaires’ Disease– Pneumonia (collapse of Pneumonia (collapse of
respiratory function)respiratory function)– Incubation time: up to 10 daysIncubation time: up to 10 days– Mortality rate 5% to 30%Mortality rate 5% to 30%
Diseases caused by Legionella Diseases caused by Legionella = Legionellosis= Legionellosis
• Pontiac FeverPontiac Fever– Flue-like illness (fever and Flue-like illness (fever and
muscle aches)muscle aches)– Incubation time: few hours to 3 Incubation time: few hours to 3
daysdays
Living EnvironmentLiving Environment Warm stagnant waterWarm stagnant water
ShowersShowers
Installations with risksInstallations with risks
Cooling towersCooling towers
Whirlpool spasWhirlpool spas
Evaporative condensersEvaporative condensers
Cooling Towers at CERNCooling Towers at CERN2323
Power: 1.25 MW to 70 MWPower: 1.25 MW to 70 MW
Volume: 5 mVolume: 5 m33 to 4000 m to 4000 m33
LHC and SPS Cooling TowersLHC and SPS Cooling Towers
Cooling Tower
Cooling Towers at the Meyrin Cooling Towers at the Meyrin SiteSite
Cooling Tower
French / Swiss Border
Analysis and LimitsAnalysis and LimitsFrequency now on a monthly basis Frequency now on a monthly basis (In the past 2-4 times per year)(In the past 2-4 times per year)
Preventive chemical Preventive chemical treatmenttreatment
100 000 UFC/l100 000 UFC/l
Stop, disinfection, cleaning, Stop, disinfection, cleaning, purgepurge
Corrective chemical Corrective chemical treatmenttreatment
1 000 UFC/l1 000 UFC/l
0 UFC/l0 UFC/l
StopStop
Preventive Chemical Preventive Chemical TreatmentTreatment
• Continuous treatmentContinuous treatment– Anti-scaling reduces Anti-scaling reduces
formation of bio-filmsformation of bio-films
• Weekly treatmentWeekly treatment– Biocide targeted on Biocide targeted on
general bio-general bio-contamination (algae, contamination (algae, fungi, bacteria)fungi, bacteria)
Corrective Chemical Corrective Chemical TreatmentTreatment• Amount of chemical depending on Amount of chemical depending on
level of contamination and volume level of contamination and volume of circuitof circuit
– Bactericide targets Legionella Bactericide targets Legionella bacteriabacteria
– Bio detergent detaches slime Bio detergent detaches slime off the surfacesoff the surfaces
Slime Surface
Annual Preventive Annual Preventive MaintenanceMaintenance
• Mechanical cleaning Mechanical cleaning – Basins, structures, …Basins, structures, …
• Purge of circuit Purge of circuit – not always practicablenot always practicable– time consumingtime consuming
• Disinfection of circuitDisinfection of circuit– Similar to corrective chemical treatmentSimilar to corrective chemical treatment
Personnel ProtectionPersonnel Protection
• All personnel performing work in or All personnel performing work in or close to cooling towers need to be close to cooling towers need to be properly trained regarding risksproperly trained regarding risks
• Zones to be signaledZones to be signaled
• Respiratory protective equipment Respiratory protective equipment need to be carried in case of exposure need to be carried in case of exposure to aerosols or in cooling towers to aerosols or in cooling towers
Conception and Follow up Conception and Follow up of Cooling Towers of Cooling Towers
– Free of dead end pipesFree of dead end pipes– Drop separators installedDrop separators installed– Good quality of supply water (Problems: Good quality of supply water (Problems:
SPS, STP18)SPS, STP18)– Accessibility for inspection and cleaning Accessibility for inspection and cleaning
givengiven– Technical documentation up to dateTechnical documentation up to date– Installation logbook put in placeInstallation logbook put in place– Follow up of water consumption and purgesFollow up of water consumption and purges
Methodical Risk Methodical Risk AnalysisAnalysis
Conclusion I: In PlaceConclusion I: In Place
– Respect of frequencies and type of analyses Respect of frequencies and type of analyses (100%)(100%)
– Preventive and corrective chemical treatment Preventive and corrective chemical treatment defined (and applied if necessary) (100%)defined (and applied if necessary) (100%)
– Annual preventive maintenance (70%)Annual preventive maintenance (70%)– Completion and review of existing procedures Completion and review of existing procedures
about preventive and corrective activities about preventive and corrective activities (60%)(60%)
Conclusion II: To-Do-ListConclusion II: To-Do-List
– Carry out a methodical risk analysis on all Carry out a methodical risk analysis on all cooling tower circuitscooling tower circuits
– Put warning signs in place Put warning signs in place – Implementation of a cooling tower LogbookImplementation of a cooling tower Logbook– Training of personnel intervening on and Training of personnel intervening on and
operating the cooling towersoperating the cooling towers– Update of hydraulic plansUpdate of hydraulic plans– ……
Conclusion III: EvaluationConclusion III: Evaluation
– Hydraulic disconnection of north area Hydraulic disconnection of north area cooling towers to SPS ringcooling towers to SPS ring
– Hydraulic disconnection of STP18 from Hydraulic disconnection of STP18 from SPSSPS
– Put purge counters in placePut purge counters in place
Budget evaluation / Schedule : ?Budget evaluation / Schedule : ?
Questions ?Questions ?