Los Alamos National Laboratory

Safety Basis: Technical Services

Analysis Services Team

POSTMAX Software


POSTMAX can be part of a two-step process to determine the 95th percentile MEOI χ/Q for a facility and accident. In the first step, MACCS2 is used to determine the dispersion values (χ/Q) according to the facility parameters and the hourly meteorological data. The models and instructions for MACCS2 are provided in NUREG/CR-4691 and NUREG/CR-6613. MACCS2 generates a table of χ/Q according to distance for each hour evaluated. POSTMAX reads the MACCS2 output, meteorological data, and site boundary distances to calculate the Maximally-Exposed Offsite Individual (MEOI) χ/Q for each hour evaluated. The MEOI χ/Q values are sorted to generate the cumulative distribution function (CDF) and the 95th percentile value is identified.


The current version of POSTMAX is 2.0. The POSTMAX V2.0 executable file (for the Windows XP operating system) is dated Tue 2/03/2009, 17:52:21 GMT.

Copyright 2010. Los Alamos National Security, LLC. This material was produced under U.S. Government contract DE-AC52-06NA25396 for Los Alamos National Laboratory (LANL), which is operated by Los Alamos National Security, LLC for the U.S. Department of Energy. The U.S. Government has rights to use, reproduce, and distribute this software. NEITHER THE GOVERNMENT NOR LOS ALAMOS NATIONAL SECURITY, LLC MAKES ANY WARRANTY, EXPRESS OR IMPLIED, OR ASSUMES ANY LIABILITY FOR THE USE OF THIS SOFTWARE. If software is modified to produce derivative works, such modified software should be clearly marked, so as not to confuse it with the version available from LANL.

Additionally, this program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2.0 of the License. Accordingly, this program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

Contact Us | Careers | Bradbury Science Museum | Emergencies | Inside LANL | Maps | Site Feedback | SSL Portal | Training

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy's NNSA © Copyright 2016 LANS, LLC All rights reserved | Terms of Use | Privacy Policy