An official website of the United States government.

We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Multi- Chamber Concentration and Exposure Model (MCCEM) version 1.2

What does MCCEM do?

  • Estimates average and peak indoor air concentrations of chemicals released from products or materials in houses, apartments, townhouses, or other residences. The data libraries contained in MCCEM are limited to residential settings. However, the model can be used to assess other indoor environments (e.g. schools, offices) if the user can supply the necessary inputs.
  • Estimates inhalation exposures to these chemicals, calculated as single day doses, chronic average daily doses, or lifetime average daily doses. (All dose estimates are potential doses; they do not account for actual absorption into the body.)

How does MCCEM work?

  • MCCEM is a user-friendly software product that estimates indoor air concentrations using a mass balance approach.
  • Maintains a library of residences, containing data on zone or area volumes, interzonal air flows, and whole-house exchange rates.
  • Allows you to tailor your analysis to a particular location, and to model air concentrations in as many as four zones for a given residence.
  • Estimates exposure for periods ranging from 1 hour to 1 year. Develops seasonal or annual exposure profiles using a long-term model.
  • Offers several different options for dealing with 'sinks'. A sink is a material (e.g., carpeting, wallboard) that can absorb chemicals from the air; the absorption can be either reversible or irreversible.

What do I need to use MCCEM?

  • Data on the indoor environment to be modeled, including type of residence, zone volumes, inter-zonal air flow rates, and air exchange rates. You can enter your own site-specific data or access the model's library to select default data from different types of residences in various geographic areas.
  • A measured or estimated pollutant emission rate as a function of time.
  • Rate constants and areas for the sinks (sinks are optional and do not need to be used to run MCCEM).
  • Occupant activity pattern (for inhalation exposure calculations).

How are MCCEM data used?

You can use MCCEM to estimate inhalation exposures to chemicals released from products or materials in residential settings or other indoor environments.

What type of computer system do I need?

  • The program is now available for use in a Windows 95 operating environment.
  • Hardware: IBM-compatible computer with 16K RAM and a pentium processor.
  • Software: Windows 95 operating system.

What is MCCEM's status and availability?

MCCEM has been peer reviewed by experts outside the EPA. MCCEM was developed under contract by Versar Inc. for the EPA Office of Pollution Prevention and Toxics, Economics, Exposure, and Technology Division, Exposure Assessment Branch (EAB).

Download MCCEM

MCCEM can be downloaded and installed using Download MCCEM.

Description of Updates for MCCEM Version 1.2 (February 2001)

MCCEM Questions/Answers

For more information about the model, contact:
Christina Cinalli
U.S. Environmental Protection Agency
1200 Pennsylvania Avenue N.W.
Washington, DC 20460
Mail Code 7406M
Phone #: (202) 564-8542
e-mail: cinalli.christina@epa.gov