An official website of the United States government.

We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

TIM Version 3.0 beta - Technical Description and User's Guidance

TIM (Terrestrial Investigation Model) is a terrestrial model used by OPP to derive quantitative estimates of the probability (or likelihood) and magnitude of mortality to birds (of the same species) exposed to the simulated pesticide.

TIM models and other TIM information.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.
  • TIM Version 3.0 beta - Technical Description and User's Guidance (PDF)(77 pp, 854 K)
    The purpose of this document is to provide technical information on version 3.0 of the Terrestrial Investigation Model (TIM v.3.0). TIM derives quantitative estimates of the probability (or likelihood) and magnitude of mortality to birds (of the same species) exposed to the simulated pesticide. This document describes how TIM derives joint distributions of exposure and toxicity to calculate the risk of mortality to birds.