What is the Restricted Entry Interval (REI) and how is it used?

• A. The period after application during which workers may not enter the treated area without PPE; duration as specified on the label.
• B. The period before application during which workers must prepare the site.
• C. A measure of pesticide potency.
• D. The time to re-enter after cleaning equipment.

Answer: (A)

Restricted Entry Interval is the time after pesticide application during which entry into the treated area is limited to protect workers from pesticide residues. The key point is that entry is restricted unless the proper personal protective equipment is worn, and the exact duration is specified on the product label. This waiting period helps ensure exposure to lingering residues is minimized, and it can last from hours to days depending on the product, formulation, and use.

The other ideas don’t fit because they describe different concepts: entering before application is not an after-application restriction; a measure of potency isn’t about time but about the chemical’s strength; and re-entering after cleaning equipment refers to a separate activity, not the post-application entry interval defined on the label.