2018 Crop Protection Guide for Tree Fruits in Washington

Pesticide Safety

Wednesday, April 25, 2018

Restricted Entry Intervals (REI) and Preharvest Interval Standards (PHI)

The restricted entry intervals (REI) and preharvest intervals (PHI) for a given material are listed on the product label. Growers are responsible for carefully reading, understanding and following these label requirements and restrictions before selecting and applying a product.

  1. The same or similar products produced by different manufacturers may not have the same label requirements and restrictions.
  2. Restricted entry intervals (REI’s) and preharvest intervals (PHI’s) are often the same within toxicity categories; however, some pesticides have product-specific intervals, higher or lower than products within a category.
  3. Different uses or rates of the same product may have different intervals.
  4. The REI of a product supercedes the PHI of a product. Example: if the REI of a product is 72 hours and the PHI is 48 hours, you must restrict entry prior to harvest for 72 hours after application.
  5. When tank mixing products, the most restrictive reentry interval applies.
Tree Fruit Research & Extension Center, 1100 N Western Ave, Washington State University, Wenatchee WA 98801, 509-663-8181, Contact Us