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Human Exposure Modeling -
Air Pollutants Exposure Model
(APEX/ TRIM.Expo Inhalation)
- General Information. The Air Pollutants Exposure Model (APEX) is a PC-based model that was derived from the
probabilistic NAAQS Exposure Model for carbon monoxide (pNEM/CO). A draft
report describing pNEM/CO is available. Reports describing prior
OAQPS applications of the pNEM to ozone also are available. APEX serves as the human inhalation exposure model within the
Total Risk Integrated Methodology (TRIM) model framework. See TRIM - General Information page for
historical information about TRIM and peer review of the TRIM and TRIM.Expo approach.
APEX is intended to be applied at the local, urban, or consolidated metropolitan
area scale and currently only addresses inhalation exposures. The model simulates
the movement of individuals through time and
space and their exposure to the given pollutant in various microenvironments
(e.g., outdoors, indoors residence, in-vehicle). The user may choose the number
and types of microenvironments to be included, select the time period of interest,
use either monitored
ambient air quality data or values provided from dispersion or other modeling
runs, and use either a mass balance approach or an empirical ratio-based (factor)
approach to estimate indoor and/or in-vehicle concentrations.
Results of the APEX simulations are provided as hourly and summary exposure and/or
dose estimates, depending on the application, for each individual included in
the simulation as well as summary statistics for the population modeled.
Two different versions of TRIM.ExpoInhalation (also known as APEX) are currently available:
APEX 3.3, for use within TRIM, and APEX 4.3, for stand alone use.
- Download Model
- User's Guide.
- Example Applications
- Peer Review and Publications
- Presentations at Scientific Meetings and Conferences
- Annual Meeting of the International Society of Exposure Analysis, 4-8 November,
2001. Charleston, South Carolina.
Overview of APEX (2.0): EPA's Pollutant Exposure Model for Criteria and Air
Toxic Inhalation Exposures. Richmond H, Palma T,
Glen G, Smith L.
- Joint Meeting of the Society of Exposure Analysis and International Society of Environmental Epidemiology. 11-15 August, 2002. Vancouver, Canada.
Further Refinements and Testing of APEX (3.0): EPA's Population Exposure Model
for Criteria and Air Toxic Inhalation Exposures. Richmond HM, Palma T, Langstaff
J, McCurdy T, Glenn G, Smith
L. (PowerPoint file with poster)
- Other Supporting Documents
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