An applicator should always read and follow label directions. Remember that the label is the law. There are several ways an applicator can misuse a pesticide, such as applying pesticides to a site not listed on the label, applying more pesticide than the label recommends, and improper storage. Improper storage could be storing pesticides near food or water or storing pesticides in something other than the original pesticide container.
Pesticide Drift
An applicator needs to keep in mind that pesticides can become volatile and drift off site. The perfect formula for pesticides drifting off site are higher temperature, higher wind, and lower humidity. We may not have low humidity in Alabama, but Alabama can certainly have high wind and high temperatures. For this reason, many pesticide applicators may want to apply pesticides early in the morning, late in the evening, or even at night. In addition, an applicator may choose to change the viscosity of the spray or use spray heads that produce a larger droplet size to reduce drift.
Filling Tanks
When filling a spray tank with a hose, do not allow the hose to go inside the spray tank. An applicator should always maintain an air gap between the end of the hose and the chemical in the tank. If for some reason water pressure is lost while the end of the hose is in the tank, back-siphoning can occur. In this case pesticides can flow from the tank into the water lines. A backflow prevention valve may prevent contaminated water from getting into a well or municipal water, but it would still be in the water lines. Maintaining the air gap between the end of the hose and the chemical in the tank would prevent this from happening.
Calibration
Calibration is an extremely important step of pesticide application. It is possible for two people to mix pesticide in two tanks the exact same way and apply a different amount of pesticide per acre. Different tips, different pressure, and different speed can change the rate of pesticide being applied. Proper sprayer calibration will determine the amount of water being applied per acre. Once the applicator determines the amount of water that is being applied per acre, they will know how much pesticide to apply to the tank.
Contact your local Extension office if you have questions about sprayer calibration. There are existing publications and videos that will explain the process step-by-step for all types of equipment including air blast sprayers, boom sprayers, boomless sprayers, granular applicators, and backpack sprayers.
Lots of information can be found on a pesticide label. It is important for an applicator to read and understand how to correctly use a product. Contact the local Extension office with any questions about pesticide safety.
Source : aces.edu