1.1 This practice provides procedures and criteria for development, modification, and use of mathematical models to integrate knowledge of environmental partitioning, transport, and transformation for use in predictive risk assessments. The exposure assessments may subsequently be used in chronic or acute health risk assessments. It does not specify models themselves, but it establishes minimum criteria for distinguishing acceptable models from those that may be incomplete, untested, or inappropriate for intended uses.

1.2 The practice is applicable to models within and among environmental media (air, water, solids, and biota) and it addresses evaluation of the generic characteristics of all such models.