How often should spray equipment be calibrated?

• A. Calibration is optional and can be skipped if it seems fine.
• B. Calibration should be done once per year.
• C. Calibration should be done after every service only.
• D. Calibration should be performed regularly according to label and company policy, typically before starting and after any changes or maintenance.

Answer: (D)

Regular calibration of spray equipment ensures you deliver the exact application rate required by the product label, every time you treat a site. This accuracy is crucial for effectiveness, safety, and environmental protection. The best practice is to calibrate in line with the product label and company policy, typically before starting each service and after any changes or maintenance to the equipment (such as switching nozzles, repairing parts, or cleaning components). If you skip calibration or calibrate only once a year or only after a service, you risk under- or over-application, which can reduce efficacy or increase drift and risk. Following the stated calibration frequency keeps results consistent, compliant, and safe.