INDAQSIndoor Air Quality Simulator

with Interactive Consumer & Lab Interface

Janet Guntly and Amber Loftis

Advisors: Dr. Tauritz and Dr. MorrisonMentors: Ekaterina Holdener and Meredith Springs

Department of Computer ScienceDepartment 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

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Equations•Steady state rate model

•Nazaroff (1986)5 and Carslaw (2007)6

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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 user-selected unknowns

• Employs the GNU Scientific Library (GSL) for Multidimensional Root-Finding9

Consumer Interface

Lab Interface

Summary

• Indoor air quality is a critical, but under-researched 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 SponsorComputing 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

References1 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?