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Legionella and Construction: How ASHRAE Standards 188 Helps Manage Risk

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Second of two presentations delivered by Dr. Janet Stout at Buffalo Industrial Chemical conference on April 28, 2017.

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Legionella and Construction: How ASHRAE Standards 188 Helps Manage Risk

  1. 1. © Special Pathogens Laboratory Janet E. Stout, PhD President & Director Research Associate Professor University of Pittsburgh LEGIONELLA AND CONSTRUCTION How ASHRAE Standard 188 Helps Manage Risk
  2. 2. © Special Pathogens Laboratory "Whoever wishes to foresee the future must consult the past…” Machiavelli
  3. 3. © Special Pathogens Laboratory Topics for Today 1. Legionnaires’ disease and risks associated with construction 2. ASHRAE Standard 188: design and construction requirements 3. Infection Control Risk Assessment (Water ICRA?) 4. Final Thoughts
  4. 4. © Special Pathogens Laboratory New Focus On Legionella Prevention
  5. 5. © Special Pathogens Laboratory First Legionella standard in the United States ANSI Approved June 26, 2015
  6. 6. © Special Pathogens Laboratory CDC Focuses on Effective Water Management For Legionnaires’ Disease Prevention (AKA ASHRAE 188)
  7. 7. © Special Pathogens Laboratory
  8. 8. © Special Pathogens Laboratory “9 out of 10 CDC investigations show almost all outbreaks were caused by problems preventable with more effective water management”
  9. 9. © Special Pathogens Laboratory LONG HISTORY OF LEGIONELLOSIS ASSOCIATED WITH CONSTRUCTION
  10. 10. © Special Pathogens Laboratory Many Studies Identified Construction Related Risk of Disease Reference Cases / Deaths Construction Risk Haley et al, 1979 49 / 15 Entry of soil into piping? Thacker et al, 1978 81 / 14 Entry of soil into piping? Parry et al, 1985 5 / 0 Entry of soil into piping? Mermel et al, 1995 2 / 2 Re-pressurization of piping Sharp, 2005 2 / 1 Water system not operated (stagnation) Stout et al, 2000 6 / 0 Water system not operated (stagnation) Sutherly, 2011 11 / 1 Water system not operated (stagnation) Reuters, 2000 4 / 0 Water system not operated (stagnation)
  11. 11. © Special Pathogens Laboratory Construction-Related Factors Impact on Water Quality • Excavation • Water main breaks • Depressurization (pressure changes) • Disruption of biofilm = brown water events • Materials of construction • Dormant periods prior to occupancy
  12. 12. © Special Pathogens Laboratory Construction Pathways for Contamination • New construction materials • Cross connections, backflow, mixing  Existing contaminated water supply  Water tempering  Disinfectant loss • Sediment disturbance  Physical  Pressure Waves • Reduced capacity of existing systems
  13. 13. © Special Pathogens Laboratory First Publication Implicating Construction
  14. 14. © Special Pathogens Laboratory First Hospital Outbreak • St. Elizabeth Hospital, Washington, DC , 1965 • 81 cases and 14 deaths • Legionella pneumophila serogroup 1 in the hospital water system • Construction  Excavation
  15. 15. © Special Pathogens Laboratory Three Episodes of Legionnaires’ Disease Related to Construction
  16. 16. © Special Pathogens Laboratory What Happened? • Three outbreaks over 10 years; 2 deaths • Legionella pneumophila serogroup 1 in the hospital water system • All associated with construction  Excavation, pile driving, re-pressurization, water main break
  17. 17. © Special Pathogens Laboratory Recommendations • Culture water system before, during and after excavation or shut down and re-pressurization of supply to the hospital • Cultures for Legionella should be carried out, especially if the supply services areas for immunocompromised patients
  18. 18. © Special Pathogens Laboratory Recommendations • Persistent discoloration of potable water should be reported to maintenance personnel and infection control
  19. 19. © Special Pathogens Laboratory Annals of Internal Medicine. 1983; 99:172-178 New Hematology-Oncology Unit
  20. 20. © Special Pathogens Laboratory Annals of Internal Medicine. 1983; 99:172-178 New Hematology-Oncology Unit • Over 10 month period  24 cases, most immunocompromised  11 deaths • 88% (21/24) admitted to recently completed hospital addition • 16 were in new hematology-oncology unit
  21. 21. © Special Pathogens Laboratory 2014: Cases Follow Renovation of Hematology-Oncology Unit
  22. 22. © Special Pathogens Laboratory New Unit • May 2014, 10 cases following completion of new hematology-oncology unit • L. pneumophila, serogroup 1 isolated from 50% (17/34) heme-onc sites • Cases stopped following shock disinfection and installation of Point-of-Use (POU) filters
  23. 23. © Special Pathogens Laboratory HOSPITAL OUTBREAK LINKED TO NEW CONSTRUCTION
  24. 24. © Special Pathogens Laboratory Hospital Construction • New $135M 12-story patient tower • Media coverage and legal proceedings • $61k for outbreak management
  25. 25. © Special Pathogens Laboratory Hospital Construction • New $135M 12-story cardiac care patient tower opened in 2010 • 11 cases; 1 death shortly after opening • 74% of distal outlets positive for Legionella within 1 month of opening
  26. 26. © Special Pathogens Laboratory No Disinfection Prior to Occupancy
  27. 27. © Special Pathogens Laboratory
  28. 28. © Special Pathogens Laboratory Identified Factors • Low flow, poor circulation due to inadequately sized pumps • Increased heat loss and low heater set point = low hot water temperature (38o C/100.4o F) • Stagnant conditions between construction and occupancy
  29. 29. © Special Pathogens Laboratory JAGS 2000; 48:1589-92
  30. 30. © Special Pathogens Laboratory
  31. 31. © Special Pathogens Laboratory Construction Impacts Water Quality
  32. 32. © Special Pathogens Laboratory
  33. 33. © Special Pathogens Laboratory Pressure Change Increased Legionella • Isolation of Legionella pneumophila from the hospital water supply • Upsurge in cases following a pressure drop caused by a pump failure • Documentation of a 30-fold increase in concentration of Legionella in the water when this “pressure shock” was artificially recreated.
  34. 34. © Special Pathogens Laboratory Pressure Change Increased Legionella 150 CFU/mL 1140 CFU/mL 5370 CFU/mL
  35. 35. © Special Pathogens Laboratory What’s in Your Water? Cross section of 4 inch pipe from hospital hot water system
  36. 36. © Special Pathogens Laboratory Community Water System Outbreak: Senior Apartment Complex Legionnaires’ disease case-finding algorithm, attack rates, and risk factors during a residential outbreak among older adults: an environmental and cohort study Benjamin J Silk, Jennifer L Foltz, Kompan Ngamsnga, Ellen Brown et al. BMC Infectious Diseases 2013, 13:291
  37. 37. © Special Pathogens Laboratory Probable Causes 1. Elderly population with comorbidity 2. Water heaters had low temperatures at the bottom of tanks (range: 70–100°F/21.1–37.8°C) 3. Low or no chlorine 4. Interruptions in water service
  38. 38. © Special Pathogens Laboratory Interruption in Water Service 1. Three-quarters (75%) of residents who were interviewed noted at least one interruption in water service since August 1st. 2. More than half of residents (56%) reported changes in the taste, odor, or color of their water during the same period.
  39. 39. © Special Pathogens Laboratory Flint Michigan
  40. 40. © Special Pathogens Laboratory Brown Water In Flint Michigan
  41. 41. © Special Pathogens Laboratory Flint Legionnaires’ Disease Outbreak
  42. 42. © Special Pathogens Laboratory Outbreak Flint, Michigan: 91 cases and 12 Deaths • April 2014 switch source water from Lake Huron to Flint River • 45 cases from June 2014 to 2015 • 46 cases from May to October 2015 • October 2015 switch source back to Lake Huron and incidence back to baseline
  43. 43. © Special Pathogens Laboratory Water Quality and Legionnaires’
  44. 44. © Special Pathogens Laboratory Water Flow and Legionella Liu et al 2006 J Appl Microbiol
  45. 45. © Special Pathogens Laboratory Study of the Effects of Flow on Legionella • Model water system constructed • Flow regimes by Reynolds number  Laminar <1000  Turbulent >10,000 • Legionella cultures of biofilm and bulk water Turbulent Laminar Stagnant
  46. 46. © Special Pathogens Laboratory Turbulent Higher Counts Recovered in Biofilm of Turbulent Flow
  47. 47. © Special Pathogens Laboratory Results and Conclusions • Results failed to show that stagnation promoted growth • Increasing flow velocity leads to higher biofilm density due to mass transfer • Higher transfer rate results in greater particle deposition
  48. 48. © Special Pathogens Laboratory Materials of Construction (Piping) and Effect of Temperature
  49. 49. © Special Pathogens Laboratory
  50. 50. © Special Pathogens Laboratory
  51. 51. © Special Pathogens Laboratory
  52. 52. © Special Pathogens Laboratory
  53. 53. © Special Pathogens Laboratory
  54. 54. © Special Pathogens Laboratory Design Elements Increase Risk • UMASS study  Sampling of newly opened BMTU identified Legionella associated with hydrostatic shock controls and electronic faucets
  55. 55. © Special Pathogens Laboratory Infection Control Hospital Epid 2012 University Study 2012
  56. 56. © Special Pathogens Laboratory Design Elements Increase Risk • Johns Hopkins study  Newly installed electronic faucets found to have greater risk for Legionella than existing standard fixtures.
  57. 57. © Special Pathogens Laboratory Water-Saving Low Flow Faucets Manual Faucet Sensor Faucet
  58. 58. © Special Pathogens Laboratory Disturbing Findings
  59. 59. © Special Pathogens Laboratory Anatomy of an Electronic Faucet A = aerator B = solenoid valve C = check valve D = inline filter
  60. 60. © Special Pathogens Laboratory BEST PRACTICES: CONSTRUCTION
  61. 61. © Special Pathogens Laboratory PLANNING
  62. 62. © Special Pathogens Laboratory Role of Infection Control Am J Infect Control 2000; 28:156-69
  63. 63. © Special Pathogens Laboratory • First Legionella standard in the United States. • Approved June 26, 2015
  64. 64. © Special Pathogens Laboratory New Responsibilities BUILDING OWNERS & FACILITY MANAGERS • Responsible for implementing ASHRAE 188 requirements and safeguards to protect against Legionella • Assist building owners with Program development and review, monitoring water systems and results interpretation WATER MANAGEMENT TEAM
  65. 65. © Special Pathogens Laboratory • Section 8. Requirements For Designing Building Water Systems
  66. 66. © Special Pathogens Laboratory Requirements for Designing Building Water Systems • General • Final Installation Documents • Balancing • Commissioning
  67. 67. © Special Pathogens Laboratory Section 8.1 General • Documentation needed when designing for construction and renovations:  System overview and intended mode of system operation  Design compliance to address hazardous conditions
  68. 68. © Special Pathogens Laboratory 8.2 Final Installation Documents • Drawings and documents of installation shall be provided to building owner
  69. 69. © Special Pathogens Laboratory Final Installation Documents • Drawing of the water distribution piping system • Material specifications for all building water system components • Safety data sheets for materials used for building water system treatment, cleaning, flushing, disinfecting • Start-up requirements for all equipment • Location of all outdoor air intakes
  70. 70. © Special Pathogens Laboratory 8.3 Balancing • All water systems shall be balanced and a balance report for each system shall be provided to the building owner.
  71. 71. © Special Pathogens Laboratory HOSPITAL OUTBREAK LINKED TO NEW CONSTRUCTION
  72. 72. © Special Pathogens Laboratory Hospital Construction • New $135M 12-story patient tower • 11 illnesses & 1 possible death after opening • Media coverage and legal proceedings • $61k for Outbreak Management
  73. 73. © Special Pathogens Laboratory No Disinfection Prior to Occupancy
  74. 74. © Special Pathogens Laboratory 8.4 Commissioning • Disinfection and flushing completed within 3 weeks prior to whole or partial beneficial occupancy • Procedures for flushing and disinfection shall meet:  Requirements of AWWA C651 or AWWA C652 or  Comply with all applicable national, regional and local regulations.
  75. 75. © Special Pathogens Laboratory Addresses A Known Risk: Delayed Occupancy
  76. 76. © Special Pathogens Laboratory Delayed Occupancy • If beneficial occupancy is delayed more than 2 weeks but less than 4 weeks after disinfection, flushing of all fixtures shall again be completed. • If beneficial occupancy is delayed 4 weeks or more after disinfection, the need for disinfection and/or flushing for unoccupied areas shall be determined by a risk assessment conducted by the Program Team.
  77. 77. © Special Pathogens Laboratory Typical Water System Commissioning • Comply with minimum building codes  Building codes do not address Legionella  References disinfection approaches for water mains (AWWA C651)…building plumbing is different  Do not provide detailed specifications for documentation by contractors
  78. 78. © Special Pathogens Laboratory Typical Water System Commissioning • Demonstrate the sanitary installation and safety of potable water systems  Confirmation is by presence/absence of coliforms or total bacteria  No correlation between Legionella and other bacteria  Legionella more resistant to chlorine than other bacteria
  79. 79. © Special Pathogens Laboratory Typical Water System Commissioning • Document that the water system is free of biological contamination, at the time of the test  Plumbing commissioning often occurs well before occupancy  Microbiological conditions and water quality can change when water sits
  80. 80. © Special Pathogens Laboratory If Delay Prior to Occupancy • Draining system  Remove all water from low points (not just freeze protection)  Flush, disinfect, re-test and document prior to occupancy
  81. 81. © Special Pathogens Laboratory Plan to Manage Risk • Questions to ask: 1. Risk level of proposed occupants 2. Extent of water system work 3. Previous Legionella environmental surveillance 4. Features that may increase risk • Reference  FGI 2014 Guidelines on Safety Risk Assessment  Infection Control Risk Assessment (ICRA) Process
  82. 82. © Special Pathogens Laboratory Minimize Risk During Construction • Be aware of contamination  Construction materials  Stagnant water / Poor circulation  Existing water system • Isolate work areas • Commission before use
  83. 83. © Special Pathogens Laboratory How About a Water ICRA? • Step 1: Identify the type of construction project or activity • Step 2: Identify the patient risk group(s) that will be affected • Step 3: Select the class of precaution based on patient risk group and project type
  84. 84. © Special Pathogens Laboratory Type of Construction Project Activity (Type A-D) Type Description A Inspection and non-invasive activities B Small scale, short duration activities which create minor water service interruptions C Work that creates a major water service interruption D Major demolition and construction projects
  85. 85. © Special Pathogens Laboratory WHEN TO CONSIDER SUPPLEMENTAL DISINFECTION
  86. 86. © Special Pathogens Laboratory Questions to Ask • Was Legionella found in the water system?  Pathogenic species?  Extent of colonization?  Colonization in sensitive areas?
  87. 87. © Special Pathogens Laboratory DISINFECTION OPTIONS
  88. 88. © Special Pathogens Laboratory Building Disinfection Not the Same as Municipal Treatment Municipal Water Treatment Building Water Treatment Chlorine Chlorine Chlorine Dioxide Chlorine Dioxide Monochloramine Monochloramine UV UV * Copper-Silver Ionization * Point of Use Filters
  89. 89. © Special Pathogens Laboratory Choosing Disinfection Method Choice of method must include infection control in addition to engineering
  90. 90. © Special Pathogens Laboratory Experience
  91. 91. © Special Pathogens Laboratory Learn From Other’s Mistakes • Outbreaks and New Construction  With renovation, installation of low flow/electronic sensor faucets  Commissioning process ineffective for Legionella removal  Long dormant periods (months) before occupying
  92. 92. © Special Pathogens Laboratory Final Thoughts: Construction and Legionella • Legionnaires’ disease and Legionella bacteria contamination can occur in new buildings and during renovation of old buildings • Risk can be managed:  Assessment and water safety plans  Think (Legionella) differently about commissioning process  Test for Legionella before and after construction affecting water quality
  93. 93. © Special Pathogens Laboratory New Responsibilities (Liabilities?)
  94. 94. © Special Pathogens Laboratory Building Operating Management (Facilitiesnet.com) ASHRAE 188
  95. 95. © Special Pathogens Laboratory With Compliance Comes More Protection 95© Copyright 2012 Special Pathogens Laboratory Compliance with Standard 188 will provide you and your facility with a compelling defense against claims of negligence.
  96. 96. © Special Pathogens Laboratory • Once you have a plan, follow it! • Compliance is measured by:  ASHRAE 188 Elements  How your plan meets or exceeds 188  Whether you have followed your plan 96© Copyright 2012 Special Pathogens Laboratory Your ASHRAE 188 Water Safety Plan
  97. 97. © Special Pathogens Laboratory WWW.SPECIALPATHOGENSLAB.COM THANK YOU Dr. Janet E. Stout President, Microbiologist info@specialpathogenslab.com

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