Probabilistic Exposure and Risk Model for FUMigants (PERFUM), developed by Dr. Richard Reiss and Mr. John Buonagurio

Background

The Probabilistic Exposure and Risk Model for FUMigants (PERFUM) was developed by Dr. Richard Reiss and Mr. John Buonagurio at Exponent to address the issue of bystander exposures to fumigants following agricultural applications. Following application of fumigants, some of the applied material may volatilize from the field and be carried downwind, causing potential exposure to persons in the vicinity of the application. The model was developed to address the regulatory need to establish buffer zones for some fumigants. The purpose of a buffer zone is to define a distance from the edge of the field where the concentration of the fumigant is at or below a level assumed to be safe. Over time, the model has been used to estimate bystander exposure for building fumigations and for agricultural applications of semi-volatile pesticides.

Our Work

The first version of PERFUM was submitted to the U.S. EPA in the summer of 2004. EPA convened a FIFRA Scientific Advisory Panel (SAP) meeting to review the model in August of 2004. The SAP meeting was held on August 24-25, 2004, and the review can be found on the EPA website along with a detailed report on the model. The SAP found the model to be “scientifically sound.” The model has been updated several times since the SAP. In June 2006, a peer-reviewed article describing the model was published by Reiss and Griffin in Atmospheric Environment.

The current version of the model is version 3.0. This version includes the capability to use AERMOD or CALPUFF, in addition to ISCST3, for the dispersion calculations. The download below includes all of the files needed to run PERFUM, and also includes a user’s manual.

PERFUM End-User License Agreement

The PERFUM model code and associated processing programs are provided by Exponent, Inc. with a no-cost, limited-use license subject to the following restrictions:

1. No part of the computer code provided may be reproduced, copied, extracted, or implemented into other models or software programs without the prior written permission of Exponent.

2. The computer programs and datasets packaged with this software may not be distributed to others without the prior written permission of Exponent.

3. With the exception of: a) Qt, used in the graphical interface; and b) gnuplot, also used in the graphical interface, permission to modify the computer code is granted to users with the provision that modified versions of the model codes must be provided promptly to Exponent, along with appropriate written documentation and instructions for use, for possible inclusion in future revisions of the models. The use of any such user-supplied changes in future model updates is at the sole discretion of Exponent. The right for unlimited distribution by Exponent of any user-supplied modifications to the code and any written descriptions of the changes, and the right for unlimited use of the modified code by all users, without compensation of any kind to the user contributing the code, is agreed to by the user as part of this licensing agreement. User-supplied code accepted by Exponent for use in future versions of the model will be acknowledged in the model code. Exponent retains the right to modify, adapt, or extend the code modifications provided as part of this agreement.

4. Qt is used pursuant to the GNU Lesser General Public License Version 3, a copy of which is available here http://doc.qt.io/qt-5/lgpl.html.

5. gnuplot is used pursuant to gnuplot’s license and copyright notice, a copy of which is available here http://gnuplot.cvs.sourceforge.net/viewvc/gnuplot/gnuplot/Copyright?revision=1.2 A copy of the gnuplot copyright notice is included in the PERFUM documentation.

6. All reports, papers, or other publications involving the use or analysis of the programs, algorithms, and methods contained in the software on this site must refer to the User's Guides on this site as the primary reference for the models. Applications involving the use of modified versions of the models and associated processors will reference the User's Guides on this site and clearly state that the code was modified by the user, and will contain a description of the modifications.

7. No part of the technical descriptions or user's instructions of the User's Guides may be reproduced without the prior written permission of Exponent.

8. It is the user's responsibility to determine if the PERFUM modeling system is appropriate for any particular application, and the user assumes all responsibility and liability for its use. Computer codes can and do contain coding, implementation, and technical errors. The software on this site is provided "as-is", and no warranty of its suitability for any particular application is provided. Exponent assumes no liability whatsoever for the use of this software. The installation and/or use of the programs on this site constitute acceptance of the terms of this agreement.