Welcome to the

Model Aquatic Health Code Network Webinar

Indoor Air Quality and Swimming FacilitiesFeatured Presenter: Ernest R. Blatchley III, Ph.D

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Please use your computer speakers to listen to today’s presentation.

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This webinar is being recorded.

We will begin at 1:30 PM Eastern.

Tuesday, January 22, 2018

Thank you for your interest and attendance!

MAHC NETWORKCMAHC UPDATES

January 22, 2019

Douglas Sackett, Executive Director

Council for the Model Aquatic Health Code

CMAHC UPDATES:

▪ CMAHC Ad Hoc Committee Update-▪ Indoor Aquatic Facility Ventilation Design and Air Quality

▪ Membership

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

CMAHC UPDATESAd Hoc Committee

❑ Indoor Aquatic Facility Ventilation Design and Air Quality ▪ Chair: Ralph Kittler, Seresco

▪ Members:Michael Beach, CDCDouglas Sackett, CMAHCChip Blatchley, Purdue UniversityJason Schallock, Anderson PoolworksJeff Nodorft, Councilman-HunsakerStephen Springs, Brinkley Sargent Wiginton ArchitectsJames Harrison, GMB HVAC and pool water filtration designerHarry Milliken, retired from Desert-AireGary Lochner, InnoventSandy Kellogg, Fairfax County Park AuthorityDon Baker, Paddock Pools

CMAHC UPDATESAd 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

CMAHC UPDATESAd 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

CMAHC UPDATESMembership

▪ Renew your membership for the 2018-2020 Conference Cycle or join for the 1st time! (memberships expired Nov. 2017)▪ https://cmahc.org/membership-signup-form.php

MAHCMore Information: Search on

“CDC MAHC” or visit the Healthy Swimming MAHC Website:

www.cdc.gov/mahc Email: mahc@cdc.gov

CMAHCMore Information: Search on “CMAHC”

or visit the CMAHC Website: www.cmahc.org

Email: info@cmahc.org

Contact Information

Doug SackettExecutive Director, CMAHC

E-mail: DouglasSackett@cmahc.orgPhone: 678-221-7218

Indoor Air Quality inSwimming 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

blatch@purdue.edu

Presented as a Webinar for the Council for the Model Aquatic Health Code

22 January 2019

11

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

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

Water Management Systems for Pools

• Physical separation for particles• Filter

• Membranes

• Disinfection/Oxidation• Chlorine is most common

• Alternatives• UV

• Ozone

• Monopersulfate

• Combinations

Image from: https://www.inyopools.com/Blog/how-a-swimming-pool-works/

14

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:H7Image from:

https://www.researchgate.net/figure/E-Coli-

CDC_fig1_311753193

Human NorovirusImage from: Kniel (2014) “The makings of

a good human norovirus surrogate,” Current Opinion in Virology, 4, 85-90.

Cryptosporidium parvum OocystImage from:

https://esemag.com/archive/0103/crypto.html

From: Hlavsa et al. (2015) “Outbreaks of

Illness Associated with Recreational Water –

United States, 2011-2012, MMWR, 64, 24, 668-672.

15

DBPs in Pools

• > 100 DBPs identified

• Include volatile and non-volatile (polar and ionic) forms

• Volatile DBPs• Inorganic chloramines (NH2Cl, NHCl2,

NCl3)

• Organic chloramines (CH3NCl2)

• THMs (CHCl3, CHBrCl2, CHBr2Cl, CHBr3)

• Halogenated nitriles (CNCl, CNBr, CNCHCl2)

• Present in all chlorinated pools

From: Weaver et al. (2009) “Volatile disinfection by-product analysis from chlorinated indoor swimming pools,” Water Research, 43, 13, 3308-3318.16

• Only trace quantities of NH3 in pools

• Reduced-N in pools• Urine

• Sweat

• Urea

• Creatinine

• Uric acid

• Amino acids

Inorganic Chloramines in Pools:Where Do They Come From?

Uric Acid3.0 mmol/d

Urea343 mmol/d

Creatinine12.9 mmol/d

Arginine0.025 mmol/dGlycine

1.80 mmol/d

Free Amino Acids: 5.7 mmol/d

Histidine1.10 mmol/d

17

Sources of DBP Precursors in Pools• Urine

• 30-35 mL/Bather (Gunkel and Jessen, 1986)(0.6-0.7 g Urea/Swimmer)

• 60-78 mL/Bather (Erdinger et al., 1997)(1.3-1.7 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: https://jezebel.com/5914953/an-anonymous-interview-with-a-grown-man-who-pees-in-the-pool

18

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, 1110-1118.

“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.”

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Health Effects Associated with Chemical Exposure in Chlorinated Pools

Bougault et al. (2009) “The Respiratory Health of Swimmers,”

Sports Med., 39, 4, 295-312.

“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(NCl3) levels and self-reported healthsymptoms in indoor swimming pool workers: dose-response relationships,” Journal of Exposure Science and Environmental Epidemiology, 23, 88-93.

“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 NCl3 levels of 40.5 mg/m3, confirming that the WHO-recommended value can be considered protective in occupational exposure to airborne NCl3 in indoor swimming pools.”

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Chiu et al. (2017), “Respiratory and Ocular Symptoms Among Employees of an Indoor Waterpark Resort — Ohio, 2016,”

MMWR, 66, 37, 986-989.

• 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

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, 148-156).• Linked to THM Exposure

• Swimming Enhanced Risk

• Eye Irritation 22

Effects of Swimmers on Gas-Phase NCl3

Date, Time

6/15 6/22 6/29 7/6 7/13 7/20 7/27 8/3

Bath

er L

oadin

g

0

20

40

60

80

100

120

140

160

Gas-p

hase N

Cl 3

Concentr

ation (

mg/m

3)

0.0

0.2

0.4

0.6

0.8

Bather Loading

Gas-Phase NCl3

WHO (2006) NCl3 Guideline

Bernard et al. (2006) NCl3 Guideline

23

Time

13:00:00 14:00:00 15:00:00 16:00:00 17:00:00

Bath

er N

um

ber

0

10

20

30

40

50

60

NC

l 3 C

oncentr

ation (

mg/m

3)

0.0

0.2

0.4

0.6

0.8

Total

NCl3 Concentration - Pool Deck

NCl3 Concentration - 1.6 m Above Deck

WHO (2006) NCl3 Guideline

Bernard et al. (2006) NCl3 Guideline

Effects of Swimmers on Gas-Phase NCl3

24

25

Re

lative

Hum

idity

(%)

35

40

45

50

55

60

65

[NC

l 3] (m

g/m

3)

0.0

0.2

0.4

0.6

0.8

1.0

Ba

the

r L

oa

d

0

10

20

30

40

50

60

70

NCl3Bather Load

[CO

2]

(pp

mv)

0

1000

2000

3000

4000

Date

11/2

7/17

11/2

8/17

11/2

9/17

11/3

0/17

12/1

/17

12/2

/17

12/3

/17

12/4

/17

[VO

C]

(pp

bv)

0

20

40

60

80

IAQ Monitoring Data

Gas-Liquid Transfer: Two-Film Model

Liquid Film

Gas Film

NCl3(aq)

NCl3(g)

lg

OH

L kHk

RTC

K

112 +=

Overall Resistance Liquid-Film Resistance

Gas-Film Resistance

Diffusion(liquid)

Diffusion (gas)

26

Gas-Liquid Transfer: Two-Film Model

Liquid FilmGas Film

lg

OH

L kHk

RTC

K

112 +=

Overall Resistance Liquid-Film Resistance27

Compound

Typical Liquid-Phase

Concentration(mg/L)

Henry’s Law Constant

(atm)

Equilibrium Gas-Phase

Concentration (mg/m3)

ReportedGas-Phase

Concentration (mg/m3)

HOCl 1.2 0.060 0.053 N.A

Cl2 0.000012 767 0.0067 N.A

NH2Cl 0.30 0.45 0.10 N.A

NHCl2 0.10 1.52 0.11 N.A

NCl3 0.070 435 23 0.1-0.7

CHCl3 0.080 185 11 0.009-0.058

CHBr2Cl 0.0040 57.3 0.17 0.002-0.003

CHBr3 0.0010 21.5 0.016 0.0008

CNCl 0.0030 108 0.24 N.A

CNCHCl2 0.00080 0.21 0.00013 N.A

CH3NCl2 0.020 154 2.3 0.016-0.07

Fro

m:W

eng,

S.C

.; W

eave

r, W

.A.;

Afi

fi, M

.Z.;

Bla

tch

ley,

T.N

.; C

ram

er, J

.; C

hen

, J.;

B

latc

hle

y II

I, E

.R.

(20

11

) “D

ynam

ics

of

Gas

-ph

ase

Tric

hlo

ram

ine

(NC

l 3)

in

Ch

lori

nat

ed

, In

do

or

Swim

min

g Po

ol F

acili

ties

,” I

nd

oo

r A

ir, 2

1, 5

, 39

1-3

99

.

28

Fraction of Total Gas-Transfer ResistanceIn Liquid-Phase: Two-Film Model

H (atm)

0.01 0.1 1 10 100 1000 10000

Liq

uid

Resis

tance/T

ota

l R

esis

tance

(K

L/

)

0.0001

0.001

0.01

0.1

1 = 0.05

Equal Resistance

HOCl

CNCHCl2

NH2Cl

NHCl2

CHBr3

CHBr2Cl

CNCl

CH3NCl2

CHCl3

NCl3

Cl2 Rn

29

Factors that Affect Air Quality in Indoor Pool Facilities

• Water chemistry

• 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

Study Objectives

• Define relationships among design, operational parameters of swimming pools and IAQ• NCl3 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

Project ScopePhase 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 Survey32

Measurements

Water Quality

• Urea (digestion, colorimetric)

• TOC

• pH

• Residual chlorine (DPD/KI)

• T

• Volatile DBPs (MIMS)

Air Quality

• IAQ Monitoring Device• NCl3, RH, CO2, VOCs

• NCl3 (air sparging)

• RH

• CO2

• VOCs

• Radon (Rn)

• Corrosion coupons33

Measurement of NCl3 in Air

Air

Flow

DPD/KI

solution

Air

Pump

A B

34

Membrane Introduction Mass Spectrometry

35

Solution

Outlet

Solution

Inlet

Outlet to

Mass SpectrometerInert Gas Inlet

Pervaporation

Membrane

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

Photos and Data Provided by Jessica MaloneyWisconsin Department of Health Services

Madison, WI 37

38

39

Turning on more aeration, windows closed

Reducing aeration processes,

windows opened.

Weekend

40

41

2 MGD Groundwater

2 MGD Aerated Groundwater

O2 In

Rad

on

Ou

t

42

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

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

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

blatch@purdue.edu

45

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