Legionella Bacteria and Microorganisms in Data Center HVAC Systems

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1 Legionella Bacteria and Microorganisms in Data Center HVAC Systems Rob Rottersman, MS, CIH Principal Ramboll #DATACENTERWORLD #CPEXPO CHANNELPARTNERSCONFERENCE.COM DATACENTERWORLD.COM

2 Data Center World Certified Vendor Neutral Each presenter is required to certify that their presentation will be vendor-neutral. As an attendee you have a right to enforce this policy of having no sales pitch within a session by alerting the speaker if you feel the session is not being presented in a vendor neutral fashion. If the issue continues to be a problem, please alert Data Center World staff after the session is complete.

3 OUTLINE 1) Introductions and Interests 2) History of Legionnaires Disease 3) Illness and Outbreaks 4) Legionella Growth Requirements 5) Current Standards and Guidelines 6) Evaluation 7) Controls

HISTORY SETTING THE STAGE July 1976: Philadelphia Bi-centennial Strains of flu with similar to the 1918 flu pandemic recently found in pigs Heightened fear of another global pandemic Michael Crichton

4 HISTORY SETTING THE STAGE July 1976: Philadelphia Bi-centennial Strains of flu with similar to the 1918 flu pandemic recently found in pigs Heightened fear of another global pandemic Michael Crichton s book Andromeda Strain to the best seller list > 4000 WWII Vets in the city for American Legion s Convention Approximately 600 staying at the Bellevue Stratford Hotel participants started getting ill fever, cough, difficulty breathing As days passed, more got ill and some died 221 people were infected and died

5 INVESTIGATION AND DISCOVERY Philadelphia inundated with investigators cause of disease elusive Theories of communists trying to take out veterans. A doctor claimed the only real consensus to develop among scientists was that this was not a bacterial disease! The cause would not be known until early 1977 Dr. Joseph McDade working to investigate another potential pathogen responsible for the disease Observed insignificant bacteria contaminating his samples Bored at a party, went to the lab and looked at the bacteria strange things were happening New experiments were done on the bacteria Legionella discovered

221 people got sick but 72 were not involved with the convention BUT.

6 WHY WAS IT HARD TO FIND? Will not grow under typical conditions. Specific requirements to culture in lab Likes high temperatures Where did it come from? 221 people got sick but 72 were not involved with the convention BUT.those 72 all walked by the Bellevue Stratford Hotel Bacteria was found in the cooling tower The bacteria was traced back and found to be responsible for many unsolved outbreaks Some as early as the 1950s.

7 Terminology Legionella the bacteria that causes legionellosis Legionella pneumophila serogroup 1 the type of Legionella most likely to cause disease Legionellosis one of two types of illnesses caused by Legionella Legionnaire's disease A type of pneumonia. Mortality rate about 10% but much higher in immune compromised Tends to affect older population Pontiac fever Flu like symptoms. Resolves untreated. Not believed to be fatal Tends to affect younger people

8 Requirements for Disease 1. Legionella bacteria must be present In sufficient quantity and Pathogenic species 2. Water containing bacteria must be aerosolized into a fine mist Respirable size droplets 3. The mist must be inhaled by a susceptible person Risk factors: advanced age, suppressed immune system, smoking, cancer, male, diabetes

9 Legionella Where and How does it Grow Legionella Bacteria is common low levels found in rivers, lakes, ponds, etc. Some survive water treatment and enter the potable water system Find a niche in building systems and multiply Biofilm, biofilm, biofilm Can live within amoeba or other protozoa Temperature important factor in growth 77 to 113 degrees F growth range rapid growth can occur between 90 and 108 degrees Starts to die at 122 degrees (slow death). Rapid disinfection above 150 degrees F

10 6,100 reported cases of Legionnaires disease in the United States in ,000 18,000 estimated

11 Where Legionella Grows in Buildings Water tanks Aerators Infrequently used equipment Water heaters Faucet flow restrictors Ice machines Water hammer arrestors Showerheads/hoses Hot tubs Expansion tanks Pipes/valves/fittings (dead end legs) Decorative fountains Water filters Evaporative coolers Cooling towers/evaporative condensors Faucets Aerosol (non steam) humidifiers Medical devices (CPAP, bronchoscopes, etc.)

12 Standards & Guidelines World Health Organization Legionella and the prevention of legionellosis 2007 ASHRAE Legionellosis: Risk Management for Building Water Systems first published in 2015 New York State Sanitary Code Part 4 Protection Against Legionella, July 2016 CDC Developing a Water Management Program to Reduce Legionella Growth & Spread in Buildings June, 2017 Center for Medicare and Medicaid Services - June, 2017 OSHA e-tool and Technical Manual Section III Chapter 7

ASHRAE - 188 Evolved from ASHRAE Guideline 12-2000 Took over 10 years to reach consensus Compliance is voluntary Unless

13 ASHRAE Evolved from ASHRAE Guideline Took over 10 years to reach consensus Compliance is voluntary Unless jurisdiction makes compliance mandatory Written in mandatory and code intended language for easy adoption into codes and regulations

14 ASHRAE 188 Building Survey Cooling Towers or Evaporative Condensers Building is more than 10 stories high (include below grade) Whirlpools or Spas Health care facility with >24 hour stays Ornamental fountains, misters, atomizers, air washes, humidifiers or other aerosol source Treatment of burns, cancer (chemo), organ or bone marrow transplant Other nonpotable water systems or devices that release water aerosols in the building or on the site. Building designed to house occupants over 65 years old Building has multiple housing units with centralized water heater

CDC Toolkit https://www.cdc.gov/legionella/maintenance/wmp-risk.

15 CDC Toolkit Asks 8 yes or no questions about your building. Click see results and will tell you if the program applies

16 Legionella Management Program 1. Assign a program team 2. Describe building water systems 3. Evaluate water systems for hazard risk 4. Identify where control measures must be applied or maintained within limits 5. Establish monitoring plan and corrective actions 6. Confirm that the program is being implemented (verify and validate) 7. Document and communicate

17 Step 1 Program Team Assign a team leader with to own and oversee the program Team members based on skills and type of building. May include: - Building owner - Building manager - Maintenance & Engineering - Risk management - Equipment contractors/vendors - Industrial hygienists/microbiologist/safety - Local health officials

18 Step 2 Describe the Building Water System

19 Step Identify Water System Risks Identify Areas Where Legionella 3 Could Grow & Spread from CDC Toolkit Areas for potential bacterial growth Sources where water could be aerosolized Locations with higher risk populations

20 Step 4 Controls and Corrective Actions Control Measures & Corrective Actions: The Basics from CDC Toolkit Identify how bacteria will be controlled Based on risks identified in step 3 What are ways to control bacteria in building water systems?

21 Step 5 Implement Monitoring and Corrective Actions See Decide How to Monitor Your Control Measures from CDC Toolkit Visual inspection Temperature Keep hot water distribution above ideal growth but beware of scalding Residual disinfectant Surrogate microbial (dip slides, plate counts, ATP) Air sampling for Legionella almost never recommended

22 Controls Once established in a system controlling Legionella can be Time consuming Expensive Frustrating Select the best control for the source. Some common options: - Clean - Eliminate source of mist - Maintain temps - Separate mist from people (barriers/contain) - Disinfect - Remove dead end legs

23 Secondary Treatment Options Supplements primary controls (some examples) Chlorine Ozone Chlorine dioxide Heat and flush Monochloramine Point of Use UV Hyperchlorination Copper/Silver Ionization

24 Step 6 Verify and Validate Verification: are we doing what we said we were gonna do? Audit Validation: is what we are doing effective May include periodic water testing for Legionella bacteria Air sampling for Legionella bacteria is almost never recommended

25 Legionella Bacteria to Test or not to Test From ASHRAE The Program Team shall determine whether testing for Legionella shall be performed and, if so, how test results will be used to validate the Program. If the Program Team determines that testing is to be performed, the testing approach, including sampling frequency, number of samples, locations, sampling methods, and test methods, shall be specified and documented. The Program Team shall include the following as part of the determination of whether to test for Legionella: a. Program control limits are not maintained in building water systems, including in water systems with supplemental disinfection. b. A health care facility provides in-patient services to at risk or immunocompromised populations. c. A prior history of legionellosis is associated with the building water system.

26 Guidelines for Data Interpretation and Response (example is from OSHA s e-tool) Table 1. Colony forming units (CFU) of LDB per milliliter Action Cooling tower/evaporative Condenser Potable water Humidifiers and Misters ,000 The levels requiring action vary for the source of exposure, based on the assumption that some routes of exposure result in a greater dose to the lung. For this reason humidifiers and similar devices (such as misters and evaporative condensers) produce aerosol mists and, therefore, need to be controlled to lower levels than cooling towers and domestic water supplies to minimize the risk of inhalation. Levels of LDB equal to or greater than the values in the table constitute a need for action, as described below: Action 1 Cleaning followed by biocide treatment of the system, if appropriate. Action 2 Cleaning and or biocide treatment Take immediate steps to prevent employee exposure.

27 Tables 3.1 & 3.2 in the AIHA Book provides additional guidance on interpretation from Culture Samples

28 Step 7 Document and Communicate Document (Pulls in steps 1-6) Program team members: names, roles, responsibilities Building description (age, use, etc) Water system description, flow diagrams, description of risks Control measures including what to monitor, where to monitor, frequency and acceptable/unacceptable results Confirmation. How will the program be verified? How will it be validated? Document collection and maintenance. Who will do the testing? How will lab reports be managed? Communicate let them know before they ask.

29 DISCUSSION

What is Legionnaires' disease?

What is Legionnaires' disease? Understanding Legionnaires disease: A Fact Sheet For Workers Organization(s): New York Committee for Occupational Safety and Health Other languages: Spanish Summary Statement: This NYCOSH fact sheet is