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Wall Paint Exposure Assessment Model (WPEM)

This page contains installations information for the Wall Paints Exposure Assessment Model (WPEM), which estimates the potential exposure of consumers and workers to the chemicals emitted from wall paint applied using a roller or a brush. To install the model, copy the 'wpemins.exe' file below into a directory; then, using Windows Explorer, double click on the file. The model will unzip automatically, and instructions for installation will follow.

On this page

What does WPEM do?

  • The Wall Paints Exposure Assessment Model (WPEM) estimates the potential exposure of consumers and workers to the chemicals emitted from wall paint which is applied using a roller or a brush.

How does WPEM Work?

  • WPEM is a user-friendly, flexible software product that uses mathematical models developed from small chamber data to estimate the emissions of chemicals from oil-based (alkyd) and latex wall paint. This is then combined with detailed use, workload and occupancy data (e.g., amount of time spent in the painted room, etc,) to estimate exposure.
  • The output of WPEM was evaluated in a home used by EPA for testing purposes and, in general, the results were within a factor of 2. The WPEM provides exposure estimates such as lfetime and average daily doses, lifetime and average daily concentrations, and peak concentrations.

What do I need to use WPEM?

Specific input parameters include: the type of paint (latex or alkyd) being assessed, density of the paint (default values available), and the chemical weiaght fraction, molecular weight, and vapor pressure.

Occupancy and exposure data are provided by the model as default values, but the model is designed to be flexible, and the user may select other values for these inputs:

For those chemicals in which the mathematical emissions model does not apply, you can enter emissions data.

  • Activity patterns on weekdays/weekends for workers or occupants, and during the painting event
  • Number of exposure events
  • Years in lifetime
  • Room size (volume); building type (e.g., office, single family home)
  • Number of rooms being painted; air exchange rates; etc.

What type of computer system do I need?

  • Processor - IBM-compatible computer with a Pentium microprocessor (minimum speed: 33 MHZ)
  • Memory - 640K
  • Hard disk space - 2 MB
  • Operating System - Windows 95 or higher

Using WPEM?

WPEM Version 3.2, a Windows-based tool is available. The model has been peer reviewed by experts outside EPA.

This model was developed under a contract by Geomet Technologies, a subsidiary of Versar, Inc. for the EPA's Office of Pollution Prevention and Toxics, Economics, Exposure, and Technology Division, Exposure Assessment Branch.

WPEM was developed under the Safe Choice Program, Designing Wall Paints for the Indoor Environment. This project was accomplished in coordination and cooperation with the National Paint and Coatings Association (NPCA), in addition to paint manufacturers and chemical suppliers.

The WPEM model can be downloaded and installed using download WPEM.

WPEM Frequent Questions

The user's guide and background document is available below as a pdf file
Wall Paint Exposure Model (WPEM) Version 3.2 User's Guide

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.

Who can I call for more information?

For more information about the model, contact:
Christina Cinalli
U.S. Environmental Protection Agency
Office of Pollution Prevention and Toxics
1200 Pennsylvania Avenue N.W. (Mail Code 7406M)
Washington, DC 20460
Phone: (202)564-8542