Ten (+) Ways to Protect Against Legionella and Other Waterborne Bacteria

Transcription

1 Ten (+) Ways to Protect Against Legionella and Other Waterborne Bacteria National Facilities Management & Technology Conference March 6, 2008 Baltimore Matthew R. Freije HC Information Resources Inc. Consulting Seminars Publications Training Research 6438 Opal Way, Carlsbad CA 92011, USA Copyright 2008, by Matthew R. Freije Outline Background Information Facts Guidelines Risk Reduction Strategies Ten (+) Key Preventive Measures to Minimize Health and Legal Risk 2

2 Legionella Rod-shaped bacteria Doubling time approx 2-6 hours Live in amoebae or biofilm 3 Biofilm Feeds Protects Can release dangerous levels Picture courtesy Montana State Univ. 4 Legionellosis Pontiac Fever Flu-like illness that doesn t require hospitalization Legionnaires disease Multi-system illness, with pneumonia, that can be fatal Initial symptoms non-specific (loss of energy, headache, nausea, aching muscles, high fever, chest pains 5

3 Contracting Waterborne Disease Contaminated source (water) Transmission (Inhalation; Aspiration) Susceptible host 6 Potential Sources of Contamination Domestic water systems (via showers, faucets, aerators, etc.)* Cooling towers* Respiratory care equipment* Humidifiers* Whirlpool spas* and baths Decorative fountains* Misters* Industrial equipment * Implicated in LD by subtype matching 7 Legionnaires Stats 8,000-18,000 cases annually in USA 65-80% cases occur sporadically 25% in hospitals, 75% community/travel Death rate roughly 5-30% 90-95% of cases go undetected 8

4 Government Guidelines Australia Belgium Czech Republic Denmark France Germany Ireland Italy Japan Latvia Malta Netherlands Norway Portugal Singapore South Africa Spain Switzerland United Kingdom United States 15 Definitions Preventive measures Designing, operating, and maintaining water systems to minimize growth Preventing transmission to people Environmental sampling Remediation Physical changes Disinfection Filtration 16 Overview of Government Guidelines Agency CDC 2003 EPA 1991 OSHA 1996 Australia EWGLI, 2003 UK (L8), 2000 WHO, 2002 PMs? Test Water Routinely? Consider in high-risk hospital areas Quarterly Valuable. Frequency not suggested. At least quarterly in DWS Quarterly for CTs. DWS if under temp minimums. Quarterly for CTs. DWS if under temp minimums. Prudent. No specific recommendation. CDC: EPA: OSHA: WHO: World Health Organization. Guidelines for drinking water quality EWGLI: European Guidelines for Control and Prevention of Travel Associated Legionnaires Disease

5 Industry Guide Documents ASHRAE, 2000 AIA, 2001 ASTM, 2002 AWT, 2003 CTI, 1996 JCAHO, Proactive: to sample to not Reduce Risk of LD Reactive Test and disinfect after LD identified Proactive Minimize Legionella in Water Systems Assume / React Assume control measures are effective until LD is identified Validate / Adjust Test water for Legionella and adjust control measures according to results. LD is Conducive to Lawsuits Environmental disease Matching strains Incubation period Guidelines and publications 20

6 Recommendations for Facility Operators Form a team Educate Assess water systems Write a management plan Implement preventive measures Test water systems routinely Remediate as necessary 21 Ten (+) Key Preventive Measures to Minimize Health and Legal Risk 22 Do s and Don ts for Domestic Water Systems 23

7 1. Ensure Cross Connection Control Have system analyzed for cross connections Install approved backflow devices where needed Test backflow devices at least annually Use All Pumps Daily Use HW Tanks Per Demand Under sizing results in low hot water temperatures Over sizing results in stagnation Retain water < 24 hrs 26

8 4. Use All Water Heaters Daily Flush Outlets In converted rooms In unoccupied rooms Before admitting a patient or guest to a room that s been vacant After plumbing repairs Chlorinate New or Renovated System Before Occupancy Also: Drain and valve off areas requiring no water Flush after minor plumbing repairs 29

9 7. Minimize Dead-legs!! Remove or cut accessible dead-legs (best) OR Valve them off (second best) OR Flush periodically (last resort) Establish policy of removing leftover piping. 30 Piping Left After Tank Removal 31 Water Meter Bypass Design A creates deadlegs between the Ts and the bypass valves, but design B does not. A M B M Drain 32

10 Dual Service Primary supply Primary supply Secondary supply Secondary supply A. The secondary supply, used only as a backup, will contain stagnant water that could contaminate the rest of the system when put into use. B. Both feeds are used continually, and tied together so that either can supply the entire facility. Ensure good flow in crossover lines. 33 Do s and Don ts for Cooling Towers Avoid Small Cooling Towers, Unless Closely Monitored Small towers implicated in numerous outbreaks Consider aircooled for load of < 150 tons Monitor small towers closely 35

11 9. Use Side Stream Filtration Approximately 3-5% of Circulated Water Reduces chemical demand Reduces suspended solids by 80-90% Select media based on particle size Backwash at least daily Poorly maintained filters create Legionella habitat Remove Deadlegs Use High-Efficiency Drift Eliminators 38

12 12. Locate Towers Far From Intakes, Accessible Areas, and Windows 39 Far From Outdoor Air Intakes 40 Away From Passers-by, Inaccessible 41

13 Locate Far From Windows 42 Web Sites for More Information epa.gov who.int cdc.gov osha.gov hcinfo.com legionella.org