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FERA Recent Additions

November 2020

November 2019

June 10, 2019

  • Updated the multi-facility version of the HEM-3 model (to version 1.55) to include an option to use an acute high value other than the default maximum. The single-facility HEM-3 version is unchanged. Also updated the nationwide 2010 Census files for the HEM-3 model with some Census block internal point locations revised to reflect population distribution and with some additional receptors for residences.  The new files can be downloaded from the HEM download page.

February 13, 2019

  • Updated the HEM-3 model to include the latest version of AERMOD (v18081), and to correct an error in HEM-3 associated with buoyant line sources. Also updated the nationwide 2010 Census files for the HEM-3 model with some Census block internal point locations revised to reflect population distribution, and updated the toxicity value files to reflect the most recent acute and chronic chronic dose-response values. The new files can be downloaded from the HEM download page.

August 24, 2018

  • Updated the nationwide 2010 Census files for the HEM-3 model with some Census block internal point locations revised to reflect population distribution. Also updated the toxicity value files to reflect the most recent acute and chronic chronic dose-response values. The new files can be downloaded from the HEM download page.

July 25, 2017

  • Updated the air pollutant exposure model (APEX aka TRIM Expo-Inhalation) to version 5.0. The new files can be downloaded from the APEX download page.

June 2, 2017

  • Updated HEM-3 to include the latest version of AERMOD. Also updated the nationwide 2010 census files for the HEM-3 model with some census block internal point locations revised to reflect population distribution. Also updated with new data that were processed with the latest versions of the AERMOD meteorological preprocessors. The new files can be downloaded from the HEM download page

December 22, 2016

  • Provided a new option for installing TRIM.FaTE in stand-alone mode. This is available on the TRIM Download Page.  Also augmented the TRIM.FaTE Public Reference Library to include chemical-specific parameter values for cadmium, arsenic and seven additional polynuclear aromatic hydrocarbons: 2-methylnaphthalene, 7,12-dimethylbenzo[a]anthracene, acenaphthene, acenaphthylene, benzo(ghi)perylene, fluoranthene and fluorene. The library and associated documentation are available on the TRIM.FaTE Download Page.

December 10, 2015

  • New version of HAPEM (HAPEM7) is available.

April 29, 2014

  • Updated HEM-3 to include the latest version of AERMOD. Also updated the nationwide 2010 census files for the HEM-3 model with some census block internal point locations revised to reflect population distribution. Also updated with new data that were processed with the latest versions of the AERMOD meteorological preprocessors. The new files can be downloaded from the HEM download page

June 19, 2013

  • Updated nationwide 2010 census files for HEM-3 model with some census block internal point locations revised to reflect population distribution. The new files can be downloaded from the HEM download page

June 6, 2013

  • New meteorological data for the HEM-3 model are now available. The new data were processed with the latest versions of the AERMOD meteorological preprocessors. The new files can be downloaded from the HEM download page

Feb 22, 2013

  • New versions of the HEM-3 model are now available. The new files can be downloaded from the HEM download page

Jan 13, 2009

Jan 12, 2009

Aug 16, 2007

  • An updated version (4.02) of the APEX model is now available, correcting a number of bugs in version 4.01 (dated 6/7/06). The new files can be downloaded from the TRIM.ExpoInhalation download page.

Aug 7, 2007

May 24, 2007

  • EPA has updated the HEM3 model to Version 1.1.0. The new version includes the ability to run both the ISCST3 and AERMOD air dispersion models. Updated census and meteorological data and a revised users guide are also provided.

May 25, 2006

  • Volume 3 - "Community Scale Assessment" - of the Air Toxics Risk Assessment (ATRA) Reference Library is now available. This volume builds on ATRA Volume 1 to describe how to evaluate and reduce cumulative air toxics risks at the local level; it also discusses other risk factors that may affect communities, and strategies to reduce those risks.

May 23, 2006

May 12, 2006

  • A correction has been made to HEM-Screen, version 2003, beta and the corrected model has been posted on the HEM Download page. The error, discovered in March 2006, was associated with its use with 20 counties in Illinois and a single county in Oregon and Oklahoma.

April 6, 2006

March 15, 2006

  • Additional TRIM example applications for training purposes have been posted. These applications involve multiple chemicals and are posted on the TRIM.Risk and TRIM.ExpoInhalation download pages.