Welcome to the Model Aquatic Health Code Network Webinar. Indoor Air Quality and Swimming Facilities Featured Presenter: Ernest R. Blatchley III, Ph.

Transcription

1 Welcome to the Model Aquatic Health Code Network Webinar Indoor Air Quality and Swimming Facilities Featured Presenter: Ernest R. Blatchley III, Ph.D Tuesday, January 22, 2018 Join the MAHC Network! and request to be added to the mailing list. Please use your computer speakers to listen to today s presentation. Questions may be submitted via the chat box. This webinar is being recorded. We will begin at 1:30 PM Eastern. Thank you for your interest and attendance!

2 MAHC NETWORK CMAHC UPDATES January 22, 2019 Douglas Sackett, Executive Director Council for the Model Aquatic Health Code

3 CMAHC UPDATES: CMAHC Ad Hoc Committee Update- Indoor Aquatic Facility Ventilation Design and Air Quality Membership

4 Indoor Aquatic Facility Air Quality Issue Poor indoor air quality has increasingly been linked to health effects Increased reporting of health events Large indoor facilities have proliferated Bather exposure times longer in these facilities Does not appear that ventilation standards are adequate to keep up with aquatics needs

5 CMAHC UPDATES Ad Hoc Committee Indoor Aquatic Facility Ventilation Design and Air Quality Chair: Ralph Kittler, Seresco Members: Michael Beach, CDC Douglas Sackett, CMAHC Chip Blatchley, Purdue University Jason Schallock, Anderson Poolworks Jeff Nodorft, Councilman-Hunsaker Stephen Springs, Brinkley Sargent Wiginton Architects James Harrison, GMB HVAC and pool water filtration designer Harry Milliken, retired from Desert-Aire Gary Lochner, Innovent Sandy Kellogg, Fairfax County Park Authority Don Baker, Paddock Pools

6 CMAHC UPDATES Ad Hoc Committee Indoor Aquatic Facility Ventilation Design and Air Quality Objectives and Outcomes Identify and assess the factors affecting air quality at indoor aquatic facilities, including: Air handling/air distribution system design, effectiveness, and operation Water quality/water chemistry Pool water treatment operation and maintenance Pool types (flat water, agitated water, water features, hot water)» Evaporation rate calculation. Bather load Spectator areas

7 CMAHC UPDATES Ad Hoc Committee Indoor Aquatic Facility Ventilation Design and Air Quality Objectives and Outcomes (continued) Review and evaluate current Model Aquatic Health Code (MAHC) requirements to determine if identified factors affecting air quality are adequately addressed. Develop revisions to the MAHC design and operational standard/best practice recommendations and corresponding Annex content to address ventilation/air quality design and operational criteria, as appropriate

8 CMAHC UPDATES Membership Renew your membership for the Conference Cycle or join for the 1 st time! (memberships expired Nov. 2017)

9 MAHC More Information: Search on CDC MAHC or visit the Healthy Swimming MAHC Website: CMAHC More Information: Search on CMAHC or visit the CMAHC Website:

10 Contact Information Doug Sackett Executive Director, CMAHC Phone:

11 Indoor Air Quality in Swimming Facilities Ernest R. Blatchley III, Ph.D., P.E., BCEE, F. ASCE Lee A. Rieth Professor in Environmental Engineering Lyles School of Civil Engineering and Division of Environmental & Ecological Engineering Purdue University Presented as a Webinar for the Council for the Model Aquatic Health Code 22 January

12 Overview Background/motivation Why do we chlorinate pools? DBPs in pools and their precursors Health effects of DBP exposure in pools Effects of swimmers on indoor air quality (IAQ) Physics of DBP transfer from water to air Planned research Scope of work Methods Pool selection Modeling Expected outcomes Relationship to other IAQ in other facility types Q&A 12

13 Swimming as Exercise, Recreation, Therapy Second most common form of exercise in the U.S. Benefits Cardiovascular health Fitness Used as therapy for a wide range of medical conditions 13

14 Water Management Systems for Pools Physical separation for particles Filter Membranes Disinfection/Oxidation Chlorine is most common Alternatives UV Ozone Monopersulfate Combinations Image from: 14

15 Chlorination of Swimming Pools Advantages Effective against bacteria, viruses Powerful oxidant Inexpensive, simple to use Disadvantages Ineffective against protozoa, especially Cryptosporidium Disinfection Byproducts (DBPs) E. coli O157:H7 Image from: e.net/figure/e-coli- CDC_fig1_ Human Norovirus Image from: Kniel (2014) The makings of a good human norovirus surrogate, Current Opinion in Virology, 4, From: Hlavsa et al. (2015) Outbreaks of Illness Associated with Recreational Water United States, , MMWR, 64, 24, Cryptosporidium parvum Oocyst Image from: html 15

16 DBPs in Pools > 100 DBPs identified Include volatile and non-volatile (polar and ionic) forms Volatile DBPs Inorganic chloramines (NH 2 Cl, NHCl 2, NCl 3 ) Organic chloramines (CH 3 NCl 2 ) THMs (CHCl 3, CHBrCl 2, CHBr 2 Cl, CHBr 3 ) Halogenated nitriles (CNCl, CNBr, CNCHCl 2 ) Present in all chlorinated pools From: Weaver et al. (2009) Volatile disinfection by-product analysis from chlorinated indoor swimming pools, Water Research, 43, 13,

17 Inorganic Chloramines in Pools: Where Do They Come From? Only trace quantities of NH 3 in pools Reduced-N in pools Urine Sweat Urea Urea 343 mmol/d Creatinine 12.9 mmol/d Uric Acid 3.0 mmol/d Creatinine Uric acid Amino acids Glycine 1.80 mmol/d Histidine 1.10 mmol/d Arginine mmol/d Free Amino Acids: 5.7 mmol/d 17

18 Sources of DBP Precursors in Pools Urine ml/bather (Gunkel and Jessen, 1986) ( g Urea/Swimmer) ml/bather (Erdinger et al., 1997) ( g Urea/Swimmer) Sweat Production is Highly Variable Competitive Swimmers: 1 L/Person/Hour (1.5 g Urea/Swimmer/hr) Less for others Natural Moisturizing Factor (NMF) Skin Attract and Retain Water from Atmosphere Amino Acids, Urea, Lactate, Easily Removed from Skin with Water (0.2 g Urea/Swimmer) Based on values reported by Institute of Sport and Recreation Management (ISRM, 2009) Image from: 18

19 Health Effects Associated with Chemical Exposure in Chlorinated Pools Bernard et al. (2009) Impact of Chlorinated Swimming Pool Attendance on the Respiratory Health of Adolescents, Pediatrics, 124, 4, CONCLUSIONS. Our data suggest that infant swimming practice in chlorinated indoor swimming pools is associated with airways changes that, along with other factors, seem to predispose children to the development of asthma and recurrent bronchitis. 19

20 Health Effects Associated with Chemical Exposure in Chlorinated Pools Bougault et al. (2009) The Respiratory Health of Swimmers, Sports Med., 39, 4, Although swimming is generally beneficial to a person s overall health, recent data suggest that it may also sometimes have detrimental effects on the respiratory system. Chemicals resulting from the interaction between chlorine and organic matter may be irritating to the respiratory tract and induce upper and lower respiratory symptoms, particularly in children, lifeguards and high-level swimmers. The prevalence of atopy, rhinitis, asthma and airway hyper-responsiveness is increased in elite swimmers compared with the general population. Fantuzzi et al. (2013) Airborne trichloramine (NCl 3 ) levels and self-reported health symptoms in indoor swimming pool workers: dose-response relationships, Journal of Exposure Science and Environmental Epidemiology, 23, In conclusion, this study shows that lifeguards and trainers experience ocular and respiratory irritative symptoms more frequently than employees not exposed. Irritative symptoms become significant starting from airborne NCl 3 levels of 40.5 mg/m 3, confirming that the WHO-recommended value can be considered protective in occupational exposure to airborne NCl 3 in indoor swimming pools. 20

21 Chiu et al. (2017), Respiratory and Ocular Symptoms Among Employees of an Indoor Waterpark Resort Ohio, 2016, MMWR, 66, 37, July 2015: complaints of respiratory and ocular symptoms January 2016: site visit Survey of employees Water, air quality measurements Chloramines in water* Endotoxin, microbial causes unlikely HVAC system problems 21

22 Health Effects Associated with Chemical Exposure in Chlorinated Pools Respiratory Problems Research in US, Europe > 100 Articles Since 1976 Asthma, Other Adverse Respiratory Endpoints Children Elite Athletes Swimming Instructors and Lifeguards Swimming Often Prescribed for Asthmatics Bladder Cancer (Villanueva et al. [2007] American Journal of Epidemiology, 165, ). Linked to THM Exposure Swimming Enhanced Risk Eye Irritation 22

23 Effects of Swimmers on Gas-Phase NCl 3 Gas-phase NCl 3 Concentration (mg/m 3 ) Bather Loading Gas-Phase NCl 3 WHO (2006) NCl 3 Guideline Bernard et al. (2006) NCl 3 Guideline Bather Loading /15 6/22 6/29 7/6 7/13 7/20 7/27 8/3 Date, Time 0 23

24 0.8 Effects of Swimmers on Gas-Phase NCl 3 Total NCl 3 Concentration - Pool Deck NCl 3 Concentration m Above Deck NCl 3 Concentration (mg/m 3 ) WHO (2006) NCl 3 Guideline Bernard et al. (2006) NCl 3 Guideline Bather Number :00:00 14:00:00 15:00:00 16:00:00 17:00:00 0 Time 24

25 IAQ Monitoring Data [NCl 3 ] (mg/m 3 ) NCl 3 Bather Load Bather Load [CO 2 ] (ppmv) Relative Humidity (%) [VOC] (ppbv) /27/17 11/28/17 11/29/17 11/30/17 12/1/17 12/2/17 12/3/17 12/4/17 Date 25

26 Gas-Liquid Transfer: Two-Film Model NCl 3(g) Diffusion (liquid) Diffusion (gas) Gas Film Liquid Film Gas-Film Resistance NCl 3(aq) 1 H2 O = + K L RTC Hk g 1 k Overall Resistance Liquid-Film Resistance l 26

27 Gas-Liquid Transfer: Two-Film Model Gas Film Liquid Film 1 H2 O = + K L RTC Hk g 1 k l Overall Resistance Liquid-Film Resistance 27

28 From: Weng, S.C.; Weaver, W.A.; Afifi, M.Z.; Blatchley, T.N.; Cramer, J.; Chen, J.; Blatchley III, E.R. (2011) Dynamics of Gas-phase Trichloramine (NCl 3 ) in Chlorinated, Indoor Swimming Pool Facilities, Indoor Air, 21, 5, Compound Typical Liquid- Phase Concentration (mg/l) Henry s Law Constant (atm) Equilibrium Gas- Phase Concentration (mg/m 3 ) Reported Gas-Phase Concentration (mg/m 3 ) HOCl N.A Cl N.A NH 2 Cl N.A NHCl N.A NCl CHCl CHBr 2 Cl CHBr CNCl N.A CNCHCl N.A CH 3 NCl

29 Liquid Resistance/Total Resistance (K L / ) Fraction of Total Gas-Transfer Resistance In Liquid-Phase: Two-Film Model HOCl = 0.05 Equal Resistance CNCHCl 2 NH 2 ClNHCl 2 CHBr H (atm) CHBr 2 Cl CNCl CH 3 NCl 2 CHCl 3 NCl 3 Cl 2 Rn 29

30 Water chemistry Factors that Affect Air Quality in Indoor Pool Facilities Mixing in liquid phase (swimmers, spray features) Mixing in gas phase (HVAC system design, operation) Water treatment, management practices But... quantitative understanding is lacking 30

31 Study Objectives Define relationships among design, operational parameters of swimming pools and IAQ NCl 3 as a sentinel compound Proxy measurements Define (quantitatively) mass transfer rates associated with mixing Baseline conditions Swimmers Water features Develop recommendations for facility design and operation to improve IAQ 31

32 Project Scope Phase I (6 months) Collaboration with Michigan State University (College of Medicine) Water Chemistry Air Chemistry Pool Characteristics Water treatment HVAC Bather Load Human Physiology Competition Pools Before/during competitions Effects of heavy bather load Phase II (12 months) Water Chemistry Air Chemistry Pool Characteristics Water treatment HVAC Bather Load Expand Range of Pool Types Therapy pools Splash parks Broad Geographic Distribution Pool Selection by 2-Stage Survey 32

33 Measurements Water Quality Urea (digestion, colorimetric) TOC ph Residual chlorine (DPD/KI) T Volatile DBPs (MIMS) Air Quality IAQ Monitoring Device NCl 3, RH, CO 2, VOCs NCl 3 (air sparging) RH CO 2 VOCs Radon (Rn) Corrosion coupons 33

34 Measurement of NCl 3 in Air Air Pump Air Flow A B DPD/KI solution 34

35 Membrane Introduction Mass Spectrometry Outlet to Mass Spectrometer Inert Gas Inlet Solution Inlet Pervaporation Membrane Solution Outlet 35

36 Pool Characterization Bather Load (digital camera) Air Handling System (return air flow, location of supply/return vents, dehumidification, heating, cooling, air T) Water Management (recirculation rate, water volume, locations of drains/returns, methods of water treatment) Maintenance (filter backwash method/frequency, water replacement method/frequency, cleaning methods/frequency) 36

37 Photos and Data Provided by Jessica Maloney Wisconsin Department of Health Services Madison, WI 37

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40 Turning on more aeration, windows closed Weekend Reducing aeration processes, windows opened. 40

41 Radon Out O 2 In 2 MGD Aerated Groundwater 2 MGD Groundwater 41

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43 Process Model: Mass-Balance Approach Mass emission rates Ambient circulation Swimmers Water features Compare model results with measurements Calibrated/verified model used as basis for development of recommendations for facility design, operation 43

44 Expected Outcomes Quantitative information about relationships of IAQ to: Pool design Pool use Water treatment HVAC system Recommendations for pool design and operation Input from swimming community 44

45 Thank You! Ernest R. Blatchley III, Ph.D., P.E., BCEE, F. ASCE Lee A. Rieth Professor in Environmental Engineering Lyles School of Civil Engineering and Division of Environmental & Ecological Engineering Purdue University 45

46 Abstract In response to need expressed by the Council for the Model Aquatic Health Code (CMAHC), a study will be launched in January 2019 to collect data illustrating relationships between the operational features of indoor swimming pool facilities and indoor air quality (IAQ). The study will involve parallel measurements of water/air chemistry in indoor pools, along with measurements of human physiological responses to exposure to the indoor air environments at these pools. Join the CMAHC, NACCHO, CDC, and principal investigator Dr. Ernest Blatchley for a presentation of this novel research. 46