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Total Risk Integrated Methodology (TRIM) Air Pollutants Exposure Model Documentation (TRIM.Expo / APEX, Version 4.5)

The Air Pollutants Exposure model (APEX) is part of EPA’s overall Total Risk Integrated Methodology (TRIM) model framework. The documents below are for APEX 4.5.  The User Guides and Technical Documentation support the TRIM.Expo Inhalation / APEX model.

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