Indoor Air Quality Project

Please visit the [[Indoor Air Quality|IAQ Summary Page]] for a list of the aims, investigators, and materials associated with the Indoor Air Quality (IAQ) hosted project.

The IAQ project hosted here investigates a wide variety of factors that impact the concentrations of air pollution that can occur in typical indoor environments. These factors include building construction, mass emission rates of different sources, ventilation rates, particle deposition rates, chemical reaction rates (including surface interaction), and indoor-outdoor particle penetration rates.

A key goal of the IAQ project is the validation and application of models for predicting indoor concentrations. Through the use of real-time monitoring techniques, it is possible to verify the performance of indoor air models, as well as to estimate model parameters. The indoor air models used in this project typically rely on a simple mass balance approach. The [[Multi-Chamber Indoor Air Quality Model (MIAQ)|MIAQ model]] is a good example.

Several key studies of the IAQ project have illustrated the combined approach of measuring airborne pollutants in specific microenvironments and validating or parameterizing deterministic models (e.g., [[A Multiple-Smoker Model for Predicting Indoor Air Quality in Public Lounges|Klepeis et al. 1996]] and [[Analytical Solutions to Compartmental Indoor Air Quality Models with Application to Environmental Tobacco Smoke ...|Ott et al. 2003]]).

Since many investigations for the IAQ project involve the general study of ventilation, they are relevant to a range of different sources of indoor air pollution. However, because secondhand tobacco smoke (SHS) is a ubiquitous pollutant and information is needed to understand exposures in everyday locations, much of the work for the IAQ project has been focused on SHS. For example, investigators have estimated source strengths for cigars and cigarettes and particle deposition for SHS emissions (e.g., [[Determining Size-Specific Emission Factors for Environmental Tobacco Smoke Particles|Klepeis et al. 2003]]).

In the remaining sections of this chapter on the IAQ project, we describe its various sub-projects in more detail.

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The MIAQ Software Project


MIAQ is a Multi-chamber Indoor Air Quality model orginally authored by William W. Nazaroff as part of his Ph.D. disseration research in the Environmental Engineering Science Department at the California Institute of Technology, Pasadena, CA.

The current maintainer of MIAQ is Dr. Neil E. Klepeis.

The program simulates concentrations of airborne particles and gaseous species taking into account processes such as deposition, ventilation, filtration, coagulation, and chemical reactivity.

MIAQ is highly-configurable research software written in Fortran-77. The source code is known to compile with GNU g77 and Absoft F77. The model requires, as input, a text file containing detailed commands.

MIAQ is free software and is released under the GNU General Public License.

The Software Distribution

[Download the complete distribution in a single compressed archive]

Note: To uncompress the tar.gz archive on Unix or GNU/Linux, use the following command in the directory where you wish the software distribution to be located:

tar zxvf miaq.tar.gz

Note that the gzipped Unix archive can be uncompressed using a variety of free and commercial Windows utilities, such as WinZip. Please visit for more information.

In the software distribution directory you will find the following text files containing useful information:

  • CONTACT - web and email addresses for more MIAQ info
  • COMPILING - how to compile MIAQ
  • EXECUTING - how to execute MIAQ
  • CHANGES - latest changes to the MIAQ source code
  • COPYING - rules for copying MIAQ
  • LICENSE - the MIAQ distribution license (GPL)
  • HISTORY - the history of MIAQ

...and the following sub-directories containing
the essential files:

  • ./src - the MIAQ Fortran-77 source code
  • ./doc - the MIAQ user's guide and manual in HTML format
  • ./bin - a pre-compiled MIAQ binary for Intel GNU/Linux
  • ./examples - some example MIAQ input and output files


[MIAQ manual in HTML Format]

The MIAQ manual, included in the software distribution, contains a complete command reference and an example input file. To use MIAQ do the following:

  • Either compile the Fortran-77 source code yourself or use the provided Intel GNU/Linux binary. See the COMPILING file in the software distribution for more information.

  • Move the binary to a location in your path (e.g., ~/bin or /usr/local/bin).

  • Type the name of the binary (e.g., miaq) on the command line followed by your chosen rootname. Do not use an extension. The MIAQ input file should have the name 'rootname.dat' and be in the current directory.

  • Please consult the MIAQ manual (included in the 'doc' subdirectory of the software distribution) for the proper format of the MIAQ input file.

  • The MIAQ output files will begin with your chosen rootname followed by a descriptive extension (e.g., 'rootname.doc' or 'rootname.aer').

  • Please see the MIAQ user's manual for a complete description of each output file.


Please cite the following references when publishing or presenting work that uses MIAQ:

  • Nazaroff and Cass (1989) ``Mathematical Modeling of Indoor Aerosol Dynamics.'' Environmental Science and Technology 23 : 157-166
  • Nazaroff and Cass (1986) ``Mathematical Modeling of Chemically Reactive Pollutants in Indoor Air.'' Environmental Science and Technology 20 : 924-934

Important Note

MIAQ is research software, intended for use by indoor air quality and exposure scientists. It has been used in a variety of studies, but has not been thoroughly tested in all respects. It currently may be executed as a stand-alone program, or as a shared library. For example, the [[Human Exposure Research Package (heR)]] includes a function for executing MIAQ aerosol dynamics simulations.

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