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Description of Updates for MCCEM Version 1.2 (February 2001)

  1. In the previous version (1.1) of MCCEM, errors in assignment of zone-specific concentrations to the exposed individual, based on the primary/secondary/override patterns from the Activities input screen, sometimes occurred for model runs longer than 7 days. These errors have been corrected.
     
  2. For some of the emission models (Emissions screen), small values were truncated to zero when writing the user inputs to a transfer file for use by the calculation routine. In some cases, the emission-rate inputs were not correctly converted to mg/day when writing the inputs to the transfer file. Both of these errors have been corrected.
     
  3. For the "Data Entry" model for emissions, time units were not saved correctly and the input screen would not refresh properly if a file was opened while information was already displayed on the input screen. Both of these errors have been corrected.
     
  4. For the Activities screen, certain user inputs would not save correctly if they were left blank. The model now issues a warning if a zone or breathing-rate field is left blank, and automatically inserts a value of zero for any time-related field (day, hr, or min) that is left blank.
     
  5. One typo was corrected on the Execution help screen.
     
  6. The Help -> About screen was updated to show Version 1.2 and February 2001.
     
  7. The MCCEM software installation package is now provided as a single (zip) file.
     

MCCEM can be downloaded and installed using Download MCCEM.

Predictive Models and Tools for Assessing Chemicals under the Toxic Substances Control Act (TSCA)

  • About the Predictive Models and Tools Under TSCA
  • Exposure and Fate Models and Tools
  • Hazard Models and Tools
Contact Us About Predictive Models and Tools for Screening Chemicals under TSCA
Contact Us About Predictive Models and Tools for Screening Chemicals under TSCA to ask a question, provide feedback, or report a problem.
Last updated on May 12, 2025
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