After calibrating spray equipment, how should you verify the accuracy of the application rate?

• A. Catch test or test area
• B. Visual estimate
• C. Trust the gauge alone
• D. Recalibrate with a different product

Answer: (A)

Verifying the actual spray rate means checking what the system delivers in real conditions, not just what the gauge reads or what you think it should look like. A catch test or test area is the best way to do this because it directly measures the amount of liquid that actually lands over a defined area.

In a catch test, you place calibrated collection devices (catch cans) or establish a defined test area along the spray path, run the sprayer at the target settings, and capture all of the spray that would reach the ground. You then measure the liquid collected, add it up, and compare it to the desired application rate (for example, gallons per acre). If the measured rate matches the target within an acceptable tolerance, the calibration is confirmed. If there’s a discrepancy, you adjust factors like nozzle flow, pressure, or traveling speed and repeat the check.

Relying on a visual estimate isn’t precise enough for determining application rate, and trusting the gauge alone can be misleading due to potential gauge errors or changes in pressure and flow. Recalibrating with a different product doesn’t verify the current rate for the product you’ll be applying.