And not so neat. We visit some neat places. Legionella Basics 3/12/2018 UF TREEO Presentation Agenda

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1 UF TREEO 2018 Presentation Agenda Managing Risks of Legionella in Building Water Distribution Systems Legionella Management Legionella Basics Regulations/Guidelines Legionella Control Legionella Field Survey VA Medical Site Suggested Best Management Practices 30+ Years in Business 250+ Municipal and Industrial/Commercial Clients Cross Connection Programs/Surveys Legionella Water Management Water Distribution Quality Studies Sampling Programs Pipe Labeling Studies System Drafting (Chilled Water, Waste Water, etc.) One Goal We visit some neat places Legionella Basics And not so neat 1

2 Recent Legionnaires Disease Cases City of Flint ( ) VA Hospitals/Properties Playboy Mansion?!?! Hotels Hospitals The Happiest Place on Earth?!?! No, Florida is not Exempt Oh No, Do not mess with our BEER!!!! Whether or not the Warsteiner brewery is found to be the breeding ground for the Legionella bacteria, officials have been making it clear that the beer is completely safe to drink. Legionella Basics Bacteria which thrives in aquatic environments - groundwater, biofilms, surface waters, soils, etc. Found in man made/engineered systems: Domestic water supplies, cooling towers, domestic hot water supplies, showers, spas, misters, decorative fountains, etc. Categorized in 1976 (at least 50 species today): Legionnaires convention Cooling Tower-cause of illness/death Legionellosis Many cases of pneumonia type illnesses throughout USA caused by Legionella bacteria (LB) Estimated 8000 to 18,000 cases per year-likely many more 1 Legionnaire s Disease/Pontiac Fever caused by inhaling/aspirating Legionella bacteria US standard/guidelines for control, management of LB: Few states have guidelines (MD, TX, and PA) PA has highest rate of reporting disease likely due to increased vigilance/monitoring 1. Marston BJ, Plouffe JF, File TM Jr, Hackman BA, Salstrom SJ, Lipman HB, et al. Incidence of community-acquired pneumonia requiring hospitalization. Results of a population-based active surveillance Study in Ohio. The Community-Based Pneumonia Incidence Study Group. Arch Intern Med. 1997;157(15):

3 Legionellosis-Data (CDC) 87% of Legionellosis cases reported ages >40 Men twice as likely to become ill vs. women Children < 15 years of age rarely become ill Most cases reported are sporadic not associated with outbreak Age, gender, smoking, alcoholism, immunosuppression, autoimmune diseases risk factors Legionellosis Preventable, and treatable with antibiotics NOT communicable 90% of cases have incubation period of 3 to 14 days At Risk Water Systems: Hot water systems, cooling towers, high pressure wash systems, Spas, decorative fountains, irrigation systems Legionella Bacteria Growth Requirements 1. Water ph 5 to 9 2. Growth range = 68 to 122 F (98 optimal) Significance? 3. Moist environments 4. Oxygen 5. Iron, sediment, scale, biofilm City Water Suppliers PWS must meet EPA National Primary Drinking Water Standards, BUT No enforceable MCL for Legionella! Only Maximum Contaminant Level Goal (MCLG) Is Legionella controlled 100% of the time in city water distribution systems? What level is safe or dangerous? City can mitigate legionella by: Chlorinating effectively Flushing programs/eliminate terminal end mains Cross Connection Control Program Water quality monitoring/treatment Private Water Systems Private Water Users must adhere to OSHA , Plumbing Code, Health Department for drinking water quality OSHA General Duty Clause Hotels, Offices, Hospitals, Factories, Grocery Stores, etc. have had reported Legionella related illnesses New standard for Legionella mitigation/risk management. ASHRAE 188 Standard General Water Management Plan Development 1. Develop Water Process Flow Diagrams (Potable and Non-Potable Water Systems) 2. Perform Hazard Identification, Analysis and Risk Characterization 3. Identify/establish Critical Control Points 4. Establish control measures/limits for critical control points 5. Plan Validation (i.e., Sampling) and Verification (Program Management) 3

4 Personal Rooms, Bath Rooms, Laundry Room (POUA) Personal Rooms, Bath Rooms, Laundry Room (POUB) Decorative Fountain (DEF1) Personal Rooms, Bath Rooms, Laundry Room (POUC) Personal Rooms, Bath Rooms, Laundry Room (POUD) Personal Rooms, Bath Rooms, Public Restroom (POUE) Kitchen and Cafeteria (POUE) 3/12/2018 Project Scope Legionella Field Survey Medical Site 1) Developed detailed domestic hot and cold plumbing drawings -12 buildings ID all plumbing equipment, evaluate cross connection measures, dead legs, operating inefficiencies 2) Assist in developing Legionella Water Management Plan for each building 3) Recommendations/Corrective Actions/Report Basic Concept-Water Safety Plan Development Process Flow Diagram Sample Evaluate Water Systems and ID Hazards Biological, Physical, Aerosol, Chemical, Radiological Can this water system allow for Legionella bacteria to amplify, become aerosolized and exposed to people? PROCESS STEPS 1. RECEIVING 2. COLD WATER POINT OF ENTRY CRITICAL CONTROL POINT 3. DECORATIVE FOUNTAIN CRITICAL CONTROL POINT 4. HOT WATER HEATING Pod A (POEA) Community Water Supply (CWS1) Pod B Pod C Pod D (POEB) (POEC) (POED) Pod E (POEE) Potable cold water system generally supplies bathing showers and sinks, toilets, urinals, ice machines, drinking fountains, laundry equipment, hose bibbs, utility sinks in Pods A through D. Pod E also has makeup to heating system, eyewash, kitchen equipment, hose bibbs, and utility sinks. Hot Water Heating Makeup Refer to Building 100 Process Flow Diagram Develop Water Management Plan - Establish Hazard Control Measures for Critical Control Points High Risk Systems Validate controls are working (Legionella sampling, etc.) 5. COLD WATER POINT OF USE CRITICAL CONTROL POINT 6. DOMESTIC HOT WATER MAKEUP CRITICAL CONTROL POINT 7. DOMESTIC HOT WATER DISTRIBUTION SYSTEM CRITICAL CONTROL POINT 8. WASTE Domestic Hot Water Supply Domestic Hot Water Return Sanitary Sewer Heat Exchanger #1 Heat Exchanger #2 Softened Hot Water Central Hot Water Central Hot Water Supply from Building 500 Supply Supply (DHW3) (Pod E Mech. Room) (Pod E Mech. Room) (DHW1) (DHW2) Thermostatic Mixing Valve Domestic Soft Hot Water Supply Domestic Soft Hot Domestic Hot Water Water Return Distribution System (DHWS1) Domestic Soft Hot Water Domestic hot water system Supply and Return from supplies kitchen operations, Building 500 to Pod E bathing showers, sinks and Kitchen only - not in use commercial clothes washing with no zone mixing/anti-scald valves. Building Field Survey-Potential Areas of Risk for Legionella Building domestic cold water supply Cross connections, dead legs, low turnover areas Domestic Hot Water Tanks/Plumbing Systems Cooling water systems Ice machines, eyewashes, baths/pools Building humidification, decorative fountains Plumbing System Risks Legionella Growth!!! Dead legs/low use water lines (hot and cold) Low chlorine Heaters below 140 F and hot water piping systems below 124 F Recirculating/return pumps not working effectively Oversized tanks/vessels or piping in relation to water demand (residence time > 24 hours) Cross connections with sanitary sewer, irrigation, etc. No insulation on piping Cold water piping becoming heated Significant water hammer/ pressure fluctuations Old piping/tanks Rubber materials, plastics vs. copper pipe 4

5 Domestic Water Heaters Study Alary, et. al Water Temperature and Legionella 40% of homes with an electric water heater reported the detection of legionella in tank 0% of homes with gas heaters reported legionella in tank Homes in older areas of community more susceptible to detection of legionella Type, age and size main factors 82.2 C 76.7 C 71.1 C 65.5 C 60.0 C 54.4 C 48.9 C 43.3 C 37.8 C 32.2 C 26.7 C 180 F 170 F Disinfection Range 158 F- 176 F 160 F 150 F At 151 F, Legionella dies within 2 minutes 140 F At 140 F, Legionella dies within 32 minutes At 122 F, Legionella can survive but do not multiply 130 F 120 F 110 F Ideal Growth Range 95 F -115 F 100 F Tempered Water 85 F -110 F 90 F Legionella Growth Range 68 F F F Water Temperature effects on Legionella Bacteria ASHRAE Guideline 1. HW Min Storage Temp = 130 F for circulated tanks 2. HW Min Storage Temp = 140 F for uncirculated tanks 3. HWR Min Temp before return to HW tank = 124 F Water heaters need capability of heating water to 158 F for disinfection Commercial water heaters have a 180 F T-stat limit Residential water heaters have a 160 F T-stat limit Instantaneous heaters typically are not capable of heating water to disinfection temperature ranges 21.1 C 70 F 15.6 C 10.0 C 60 F Below 68 F, Legionella can survive, but are dormant. Cold water in storage tanks, piping, decorative fountains and other equipment, ideally, should be kept below 68 F 50 F Scalding Considerations Temperature Amount of Time to Cause Serious Burn 120 F More than 5 Minutes 125 F 1.5 to 2 Minutes 130 F 30 Seconds 135 F 10 Seconds 140 F 5 Seconds 145 F <5 Seconds 150 F 1.5 Seconds 155 F 1 Second Maintain tank temperature at >140 F Maintain hot water piping at > 124 F Routine tank/system pasteurization Routine system draining Domestic Hot Water Tank and Hot Water System Control Measures Inspect/test master mixing valves Return pump on at all times At least daily turnover of tank Ensure freshest water possible supplies tank (high Cl 2 ) Inspect expansion tanks regularly Install antiscald valves where required Maintain/disinfect shower heads and hoses Insulate hot water piping Flush stagnant/low flow areas Copper piping-hot water Domestic Hot Water Tank and Hot Water System Control Measures Mixing valves-install as close to end use as possible (i.e., sink, etc.) Use point of use/instantaneous water heaters where possible Cross connections (i.e., janitor sink soap dispensers) Domestic Hot Water Source DHW Return Pump Domestic Hot Water Systems Sinks, Showers, etc. 124 F Hot Water Supply Antiscald Protection Required 110 F required at outlets ASSE 1017, ASSE 1062, etc. Sinks, Showers, etc. 124 F Hot Water Return 5

6 Cross-Connection Improper Backflow Preventer Hot Water Source Cross-Connection Improper Backflow Preventer Hot Water Source Pipe supply material Pipe labeling Piping leaks Expansion Tanks Hot Water Vessel Temperature Settings Hot Water Outlet Temperature Hot Water Return Temperature Check Valve Installations Master Mixing Valves Hot Water Return Pumps Hot Water Vessel Recirculation Pumps Number of outlets served Types of outlets served Showers, sinks, kitchen operations Water Supply Soft Water, City Water Quality Might be time for a new tank? System Leaks May be indicative that equipment needs maintenance or replacement Impacts heating capacity Case Study- Insufficient Heat in System Case Study-Insufficient Heat in System Target Domestic Hot Water Piping System Temperature = 124 F Semi-instantaneous heat exchanger set F (Typ. 2) 5 Wing - Community Living Center Highest temperature in piping system is 112 F, recorded 15 feet from heat source Why? Target Domestic Hot Water Piping System Temperature = 124 F Semi-instantaneous heat discharge F Recirculating and return pumps working Highest use is immediately downstream = Kitchen Operations = high hot water use 6

7 Case Study-Insufficient Heat in System Case Study-Insufficient Heat in System Domestic Tempered Hot Water Master Thermostatic Mixing Valve Downstream Heating Tempered water temperature gauge = 124 F Domestic Hot Water 124 F Domestic Cold Water 15 Feet Downstream of Mixing Valve Gauge = 108 F Mixing valve and temperature gauge malfunctioned! Staff assumed hot water was at 124 F Case Study-Insufficient Heat in System Domestic Hot Water Return Piping System Temperature = 104 F Temperature difference of 4 to 8 F piping system from supply to return May possibly need supplemental return pump 2 separate return line systems, 1 pump Consider dedicated heater for kitchen operations Maintain temperatures <67 F Rotate booster pumps weekly Eliminate any dead legs in cold water piping system Flush known low use areas Test backflow prevention assemblies Manage expansion tanks, hammer arrestors Domestic Cold Water System Control Measures Flush strainers Insulate cold water piping, run cold water pipe below hot Maximize chlorine levels through flushing, strategic plumbing Eliminate cross connections New Construction utilize backflow preventer to isolate area, chlorinate new mains (AWWA C651-14) Cross-Connection Improper Backflow Preventer Ice Machines Eye Washes Water supply - backflow prevention Filters (type, change frequency) Hands free, manual scoop Water cooled vs. air cooled condenser Population Served (high risk population vs. general public) Ice Machines may require routine cleaning/disinfection/inspection Water supply cold vs. tempered Shared supplies Pipe supply material Shower vs. eyewash only Weekly Flushing Schedule 7

8 Dead Legs Pressurized sections of water piping no use/flow Bacteria proliferation (i.e., Legionella) and corrosion issues May introduce water of poor water quality into active mains Dead legs should be eliminated/removed, or disconnected and capped in place Pipes Pressurized w/ Water and Capped Dead Legs Dead Legs? Dead Legs Pipes Pressurized w/ Water and Capped Pipe Pressurized w/ Water and Capped Operational Dead Leg-Backup Soft Water Domestic Soft Hot Water Backup Backflow Prevention Assemblies Test annually or as required Flush strainers at least annually Failed assemblies may allow for contaminated water to enter distribution system (i.e., bacteria such as Legionella), thus posing hazard Fire Systems take precautions during fire flow tests/assembly testing X Domestic Hot Water Supply 8

9 Cross-Connection Subject to Backpressure Chemically treated pressurized cooling water may contain Legionella backflow into potable water supply Processes and Kitchen Share Supply- Hospital Domestic Water System Exposed to Process Soft Water. What s wrong here? Potable water supply with no backflow protection Case Study Process Cold Soft Water Double Check Valve Assembly (Backflow Preventer) Water Softeners (2) Reverse Osmosis Systems/Process Heat Exchangers Humidification Ice Machine Domestic Hot Water Heat Exchanger Hospital Domestic Hot Water Supply Backup Line Hospital Domestic Cold Water Supply Backup Line/Dead Leg Kitchen Operations Automated Endoscope Reprocessors Ice Machine Supply.look closely.what is this?? Cross-Connection Improper Backflow Preventer Cooling Towers 9

10 Cross-Connection Improper Backflow Preventer Cooling Towers Water supply - backflow prevention Biofilm/growth Location of tower, relation to air intakes Chemical treatment program Dead legs/seasonal usage considerations Side stream devices Number of chillers/absorbers Free cooling Case Study - Capacity vs. Usage - Holding Tank Tank supply to Cooling Tower bypassed direct, highly chlorinated city water feed - Low turnover in tank frequent Legionella bacteria detected in samples Decorative Fountains Building Humidification Decorative Fountains Water supply - backflow prevention Biofilm/growth Location of fountain Chemical treatment program, aeration Water turnover Proximity of seating Requires routine cleaning, water turnover, biocide evaluation, etc. Softening Humidification Steam Generation Building Humidification Other Systems Building Humidification Water supply - backflow prevention Steam vs. water Water treatment (RO and chlorine depletion, softening, etc.) Water quality (turnover, temperature, quality, etc.) Pipe supply material Areas served Systems to Evaluate/ Inspect.. Dialysis Systems Dental Chairs/Lines Nebulizers/humidifiers Pharmacy/compounding Softeners Hydrotherapy/Baths And more.. 10

11 Best Management Practices FACILITY BEST MANAGEMENT PRACTICES 1. Perform an in-field assessment of building water systems for Legionella risk to include evaluating water equipment, cross connections, dead legs, plumbing materials, etc. 2. Develop a Legionella Water Management Plan 3. Maintain accurate data management/records, training, system drawings/information Benefits of Water System Program Management Minimize Risk Improved Safety Reduced Operational Costs (accurate documentation, mapping) Improved efficiencies Regulatory & internal guideline compliance Secondary Disinfection Methods Thermal Shock Treatment (Pasteurize) Shock Chlorination(>10mg/L residual) May require water tanks to be 20 to 50 mg/l Continuous Supplemental Chlorination (2-4 mg/l) Copper- Silver Ionization (continuous) Monochloramine Point-of-use Filtration Further Information Steve Fox sfox@hydrocorpinc.com HydroCorp 5700 Crooks Road, Suite 100 Troy, MI hydrocorpinc.com 11