Where can pyrethroid sprays be applied on a building's exterior?

Where can pyrethroid sprays be applied on a building's exterior?

• A. Inside walls
• B. On exterior walls that are exposed to rainfall
• C. On ground adjacent to the building
• D. Underside of eaves or soffits, doors and windows protected from rainfall by a covering, overhang, awning or other structure

Answer: (D)

Exterior sprays with pyrethroids are meant for surfaces that stay dry, since rain will wash away or degrade the product and shorten its effectiveness. The best place to apply them is where the exterior surface is protected from rainfall by something like an overhang, awning, or other structure—specifically the underside of eaves or soffits and the areas around doors and windows that remain sheltered. These protected locations allow the product to dry and persist long enough to deter or kill insects as they attempt to enter. Applying on exterior walls that are exposed to rainfall would quickly wash off the chemical and reduce control. Spraying inside walls isn’t an exterior application. Spraying the ground next to the building isn’t ideal for a lasting barrier and can create other issues with runoff and non-target exposure.

Exterior sprays with pyrethroids are meant for surfaces that stay dry, since rain will wash away or degrade the product and shorten its effectiveness. The best place to apply them is where the exterior surface is protected from rainfall by something like an overhang, awning, or other structure—specifically the underside of eaves or soffits and the areas around doors and windows that remain sheltered. These protected locations allow the product to dry and persist long enough to deter or kill insects as they attempt to enter.

Applying on exterior walls that are exposed to rainfall would quickly wash off the chemical and reduce control. Spraying inside walls isn’t an exterior application. Spraying the ground next to the building isn’t ideal for a lasting barrier and can create other issues with runoff and non-target exposure.