How should you calibrate spray equipment to ensure the correct pesticide rate?

• A. Determine output per unit time with pump and nozzles, adjust pressure and nozzle type to match labeled rate, and verify with a catch test or test area.
• B. Calibrate by measuring volume of spray in a bucket without considering pressure.
• C. Only adjust nozzle type; no measurement.
• D. Use the label rate as estimate with no testing.

Answer: (A)

Calibrating spray equipment means ensuring the amount of pesticide you apply over a given area matches the label rate. To do this, you first determine how much spray the pump delivers per unit of time with the current nozzles. This tells you the actual flow that would reach the target area at a given travel speed. Then you adjust the system—changing operating pressure or the nozzle type—so the output aligns with the labeled rate for the conditions you’ll use. After adjusting, you verify the result with a catch test or by applying to a test area and calculating the actual rate delivered. This verification is essential because real-world factors like nozzle wear, pressure fluctuations, and travel speed can shift the rate even if the nominal settings look right. By tying the measured output to a known rate on the label and confirming with a test, you ensure accurate and safe pesticide application.