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Chemical Mass Balance (CMB) Model

The Chemical Mass Balance (CMB) Model EPA-CMBv8.2 is one of several receptor models that has been applied to air quality problems over the last two decades. Based on an effective-variance least squares method (EVLS), EPA has supported CMB as a regulatory planning tool through its approval of numerous State Implementation Plans (SIPs) which have a source apportionment component. CMB requires speciated profiles of potentially contributing sources and the corresponding ambient data from analyzed samples collected at a single receptor site. CMB is ideal for localized nonattainment problems and has proven to be a useful tool in applications where steady-state Gaussian plume models are inappropriate, as well as for confirming or adjusting emissions inventories. Guidance in their use may be found in Section 5.2.2 of the " Guideline on Air Quality Models".

Chemical Mass Balance Model EPA-CMB8.2
Windows-based EPA-CMB8.2 represents the latest advancement in the CMB series and replaces CMB7.   EPA-CMB8.2 has been subjected to peer review and is available for regulatory applications.

Model Code
README - Supplemental
Source Code

Model Documentation
Users Manual
CMB Protocol
Peer Review
Response to Peer Review
Model Change Bulletin
Presentation with Demo (A&WMA's 98th Annual Conference, 23 June 2005; Minneapolis, MN)

Evaluation Data Sets
Test Data Set  
Other Data Sets Formated for CMB Input
   Portland Aerosol Characterization Study (PACS):
     Data Set
   San Joaquin Valley Fine (SJVF):
     Data Set
   Coastal Oxidant Assessment for Southeast Texas (COAST):
     Data Set
   North American Research Strategy for Tropospheric Ozone (NARSTO):
     NARSTO Documentation
     Data Set
   Northern Front Range Air Quality Study (NFRAQS):
     NFRAQS Executive Summary
     Data Set

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