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IIOAC - Common Questions and Answers

Q: How should I send comments to you about IIOAC?

A: EPA is interested in your feedback from both a scientific and a computer user perspective.

Eva Wong, U.S. EPA
U.S. Environmental Protection Agency
Office of Pollution Prevention and Toxic
Risk Assessment Division

Q: Where can I find information about how the model calculates concentration in the environment and exposures?

A: The IIOAC user manual documents all equations used in the model.

Q: Has the IIOAC been peer reviewed?

IIOAC is an adaptation of EPA’s AERMOD. AERMOD is EPA’s recommended air dispersion model and has been subject to peer review and model evaluation.

Q: When will OPPT use IIOAC?

A: IIOAC, based on AERMOD, provides another air dispersion model that OPPT can use to estimate air concentrations and air deposition. Depending on the specific modeling requirements of a chemical substance, OPPT may use Screen3 (within E-FAST), IIOAC, or AERMOD itself to estimate air concentrations.