$295 Member/$345 Non-Member

Recorded at AIHce EXP 2021

This PDC provides an introduction to IH Mod 2.0, an Excel-based freeware modeling tool available on AIHA's website. IH Mod 2.0 is used for evaluating workplace and consumer inhalation exposures that include Monte Carlo Simulation. Participants will learn: a) about the IH Mod 2.0 exposure models and support files; b) to select the appropriate models and parameter inputs; and, c) whether predictions should be based on a deterministic or probabilistic approach. Case studies will illustrate these models: well-mixed room (box), two-zone (near field/far field), near-field plume, and turbulent eddy diffusion. The following topics will be presented: 1) characterizing exposure distributions using Monte Carlo simulation; 2) interpreting model outputs as concentration curves or time-weighted averages; and, 3) issues relating to data quality, model validation, and model limitations. A series of case studies/scenarios will demonstrate how to apply IH MOD 2.0 to IH exposures.


Participants should have a knowledge of Microsoft Excel, enabling macros and capability to install software prior to the course on a notebook/laptop.

Course outline

  • Mathematical Modeling in Exposure and Risk Assessment
  • Historical Evolution and Development of IH MOD
  • IH Mod 2.0 – Addition of Advanced Monte Carlo Simulation Tool
  • Variability and Uncertainty in Exposure Estimates
  • Description of Deterministic Versus Probabilistic Approaches
  • Overview of Exposure Models
  • Key Input Parameters
  • Case Study Examples
  • Data Quality Issues and Model Limitations
  • Future Directions
  • Q & A Review

Course outcomes

Upon completion, students will be able to:

  • Identify situations where exposure models may be useful.
  • Demonstrate knowledge of the types of models covered in the PDC.
  • Summarize the parameters required for each model and data sources.
  • Select appropriate model(s) for different exposure scenarios.
  • Determine whether to use a deterministic or probabilistic approach.
  • Define input parameters for point estimates and exposure distributions.
  • Apply models and interpret model results.
  • Recognize data gaps and model limitations.
  • Complete an uncertainty analysis of exposure estimates.

Time to complete

Participants will have 90 days from the date of purchase to view the session recordings and submit the online evaluation for credit.


Have questions or need additional information? Contact us.


Alan Rossner, PhD, CIH, FAIHA

Dr. Rossner is Director of the Environmental Health Science and Environmental Science & Policy undergraduate programs at Clarkson University. He is also Associate Director of Clarkson’s Institute for a Sustainable Environment. He received his Bachelor of Science degree in Biology from Clarkson University, Masters of Science degree in Environmental Health from the University of Washington, and PhD in Occupational Health from McGill University in Montreal, Quebec, Canada. Prior to coming to Clarkson University in 1995, he spent 10 years working as an industrial hygienist with Oregon OSHA (2 years), The Boeing Company (5 years) and as an industrial hygiene consultant (3 years) in the Northwest. His teaching and research interests are in human exposure to hazardous chemicals and agents. While at Clarkson, Dr. Rossner has conducted research in the areas of exposure assessment and environmental health science. Dr. Rossner has tried to direct his research in areas that minimize human exposure to contaminants, improve working conditions, improve living conditions and minimize risk of disease. His current research projects encompass three areas: 1) The development of air sampling methodologies, 2) Exposure assessment strategies for occupational and environmental air sampling, and 3) Indoor/outdoor air contaminant monitoring. Dr. Rossner has served as Chair of the AIHA’s Risk Assessment Committee and taught in a variety of Professional workshops over the last two decades. He is an AIHA Fellow as well as board certified in the Comprehensive Practice of Industrial Hygiene by the American Board of Industrial Hygiene. He served on the Board of Directors of ACGIH for six year.

Thomas Armstrong, PhD, CIH, FAIHA

Tom established TWA8HR Occupational Hygiene Consulting, LLC since 2008. Tom earned his degrees, last PhD in Environmental Engineering, from Drexel University. He is a CIH and a Fellow of the American Industrial Hygiene Association. Tom is a longtime member of the American Industrial Hygiene Association and often also the Society for Risk Analysis. He retired from ExxonMobil Biomedical Sciences in 2008. He developed and applied exposure assessment methods supporting many influential epidemiology studies. His research also includes mathematical methods to estimate exposures to chemicals, statistical methods for industrial hygiene data, quantitative risk assessments for Legionella and Legionnaires’ disease. He has numerous publications including chapters in books on exposure assessment strategies, mathematical modeling to estimate exposure, and risk assessment approaches. He remains active in AIHA risk assessment, epidemiology, and exposure assessment committee. He has been a member of National Academy of Sciences Risk Assessment review committees and peer review panels for US EPA occupational and consumer product chemical risk assessment.

Dr. Pamela Williams, MS, ScD, CIH

Dr. Pamela Williams is a Principal at E Risk Sciences, LLP, an independent scientific consulting firm that provides sound analyses and tools to support risk-based decision-making related to human health and the environment. She is also a Clinical Assistant Professor in the Department of Environmental and Occupational Health at the Colorado School of Public Health as well as a Fellow with the non-profit organization Toxicology Excellence for Risk Assessment (TERA). Dr. Williams specializes in assessing human exposures and health risks in environmental, community, and occupational settings. Her particular areas of expertise include human health risk assessment, exposure science, exposure modeling, and uncertainty analysis. She is past President of the Society for Risk Analysis (SRA) and past Chair of AIHA’s Risk Committee. Dr. Williams has both a Master of Science (MS) and Doctor of Science (ScD) degree from the Harvard School of Public Health. She is also a certified industrial hygienist (CIH).