INDAQS
Indoor Air Quality Simulator
with Interactive Consumer & Lab Interface
Janet Guntly and Amber Loftis
Advisors: Dr. Tauritz and Dr. Morrison
Mentors: Ekaterina Holdener and Meredith Springs
Department of Computer Science
Department of Civil, Architectural, and Environmental Engineering
Sponsored by CRA-W
Motivation
• Among top five environmental health
risks1
• Americans spend 90% of time indoors2
• Exposure to pollutants can result in
allergies, irritations, respiratory
illnesses, and cancer4
• Costs US roughly $160 billion a year3
Goals
• Raise consumer awareness
• Improve consumer health
• Provide easy computational research
tool
• Undergraduate research
◦ Interdisciplinary collaboration
◦ Extracurricular learning
◦ Exposed to graduate style learning
Questions
• Consumer
◦ What happens to the air quality in my
home when I use cleaning supplies?
◦ Is my air purifier improving my indoor
air quality?
• Researchers
◦ What is the deposition velocity and is
a mistake possible?
◦ What is the concentration of ozone in
the chamber for α-pinene
experiments?
Existing Simulations
• CONTAM
◦ Overly complex for consumers
◦ http://www.bfrl.nist.gov/IAQanalysis/
• University of Texas at Austin
◦ Insufficient for our types of questions
◦ No data interpretation
◦ http://www.ce.utexas.edu/bmeb/index.cfm
Equations
•Steady state rate model
  V  CO ,o  EO    V  CO ,in   qa a  CO3 ,in 
3
3
3
a
1


1

1
  Ai  CO3 ,in 
i  v 
v
 t ( f    (1  f )   ) 

j
i

4  O3 ,i
k
O3 , j
 C j ,in  CO3 ,in
j
  V  C j ,o  E j    V  C j ,in

Y
n ,O3 , j
j
 kO3 , j  C j ,in  CO3 ,in 
q
a
a  C j ,in
a
•Nazaroff (1986)5 and Carslaw (2007)6
Developing Model Input
• Determined acceptable ranges and
estimated default values
• Aggregation of values identified during
extensive literature search
Example: Air Exchange Rate
• Murray and Burnmaster (1995)7
◦ Range: 0.05 - 6.5
◦ Mean for US: 0.5
◦ Mostly for windows closed
• Howard-Reed (2002)8
◦ Range: 0.10 – 0.82 windows closed
0.44 - 1.66 windows open
Simulation Engine
• Common backend for consumer and
lab interfaces
• Solves the set of equations for userselected unknowns
• Employs the GNU Scientific Library
(GSL) for Multidimensional RootFinding9
Consumer Interface
Lab Interface
Summary
• Indoor air quality is a critical, but underresearched health concern
• Determined acceptable variable ranges
and values for common indoor air
equations
• Common simulation engine powers
both lab and consumer interfaces
Future Work
• Validate solutions and acceptable
ranges
• Dynamic temporal-spatial equations
• Lab tests for a specific emission or
source
• Add more features to the interfaces
◦ More scenarios
◦ Add animation
◦ Advanced integrated interface
Impacts
• Template simulation engine for other
uses (i.e., medical)
• Empower consumers to make informed
decisions
• Increase productivity of researchers
Primary Sponsor
Computing Research Association
Committee on the Status of Women in
Computing Research (CRA-W)
Program: Multidisciplinary Research
Opportunities for Women (MRO-W)
Missouri S&T Sponsors
• Department of Computer Science
• Department of Chemical Engineering
• Department of Civil, Architectural and
Environmental Engineering
• Women’s Leadership Institute
• Academic Affairs
• Intelligent Systems Center
References
1 Guide to Air Cleaners in the Home. United States Environmental Protection
Agency. Office of Air and Radiation, Oct. 2007.
2 Spengler, John and Samet, Jonathan. Indoor Air Quality Handbook. New York:
McGraw-Hill, 2000.
3 Fisk, William. E-Vision 2000 Conference, 11-13 Oct. 200, Washington DC. Health
and Productivity Gains from Better Indoor Environments and Their. Berkeley:
Lawrence Berkeley National Laboratory, 2000.
4 Godish, Thad. Sick Buildings: Definition, Diagnosis and mitigation. Boca Raton:
Lewis Publishers Inc., 1995.
5 Nazaroff, William W., and Glen R. Cass. "Mathematical Modelling of Chemically
Reactive Pollutants in Indoor Air." Environmental Science & Technology 20
(1986): 924-34.
6 Carslaw, Nicola. "A new detailed chemical model for indoor air pollution."
Atmospheric Environment 41 (2007): 1164-179.
7 Murray, Donald M., and David E. Burnmaster. "Residential Air Exchange Rates in
the United States: Empirical and Estimated Parametric Distributions by Season
and Climatic Region." Risk Analysis 15 (1995): 459-65.
8 Howard-Reed, Cynthia, Lance A. Wallace, and Wayne R. Ott. "The Effect of
OPening Windows on Air Change Rates in Two Homes." Journal of the Air &
Waste Management Association 52 (2002): 147-59.
9 <http://www.gnu.org/software/gsl/manual/html_node/
Multidimensional-Root_002dFinding.html>.
Questions?