AIHce Indianapolis



PDC 705
Exposure Modeling: Using Mathematical Models to Estimate Exposure

intermediate | 2.67 CM Points/ 16 Contact Hours/ 2.0 CEU/COC Points | Saturday & Sunday | 8:00 a.m. - 5:00 p.m. | Limit: 35

PublicationOnline Community

Exposure Assessment Strategies, Risk Assessment and Management

This PDC reviews the basis and application of exposure-modeling techniques to evaluate airborne contaminant concentrations relevant to IH exposure issues. His will use models to estimate concentrations when monitoring is unavailable, including:

  • Emergency response scenario pre-planning;
  • Exposure event reconstruct, and
  • New chemical/process approvals.

European REACH legislation is one of the current drivers for model use. Fundamental laws of chemistry and aerosol science upon which the models are based, and seven of the most common room models will be presented. The benefits and limitations of each model will be discussed. Case studies will illustrate how to use these models and will provide participants with experience in how to select the most appropriate model for their exposure scenario.

Value Added:
Receive a copy of Using Mathematical Models for Estimating Occupational Exposure to Chemicals. A Microsoft Excel–based spreadsheet will be provided to explore models for estimating exposure.

Understanding of Microsoft Excel and enabling macros.

Learning Aids:
Participants must bring a laptop and have the capability to install software.

Upon completion, the participant will be able to:

  • Appropriately apply, and interpret models covered in the PDC.
  • Describe the role of mathematical modeling in exposure assessment.
  • Use the mathematical models presented in the PDC.
  • Select the appropriate models for different scenarios, and will identify the differences in prediction using different models.
  • Recognize the mathematical basis of the models.
  • Complete a simple uncertainty analysis of model exposure estimates.


  • Day One
    • Introduction (why model?) and background brief background on IH modeling
    • Physical chemical principles
    • VP
    • Ideal Gas Law
    • Raoult’s Law (with/without activity coefficients)
    • Henry’s Law
    • Generation rates
    • More examples
    • Exercises
    • Open IH Mod small spill
    •  Alpha calculation
    • Well-mixed box, also with back pressure (work IH model)
    • WMR, exp decreasing ER (ALPHA)
    • Q&A
    • Review
  • Day Two
    • Two box model: Constant emission rate
    • Two box model: Exponentially decreasing contaminant emission rate
    • Turbulent eddy diffusion models
    • Dermal modeling
    • Small spill model (IH Mod)
    • Stochastic modeling discussion, examples
    • CFD
    • EPA sites (WPEM, emission factors, NERL) expert system models (ART)
    • Statistical models, possibly more as time permits
    • Additional case studies and applications
    •  Closing review

Transfer of Knowledge:
Instructors will evaluate participants understanding of the materials presented based on:

  • Post course test
  • Hands-on demonstrations and practicum
  • Practice exercises
  • Workshops
  • Group activities
  • Interactive games

Sponsoring Committee:
Exposure Assessment Strategies

Important PDC dates:

  • May 18 — E-handout download instructions are e-mailed.
  • June 1  — Contact the AIHA if you have not received your e-handout e-mail.
  • June 1  — AIHce 2012 online communities for collaborative learning open.
  • June 15-17 — AIHce 2012 PDCs are presented. Participants must bring a printed or electronic copy of their PDC handout.
  • August 31 — AIHce 2012 online communities for collaborative learning close.
  • August 27 Educational transcripts updated and available for download