What precaution ensures water contamination is prevented during pesticide application?

Filling a sprayer from a separate water tank is a precaution that effectively helps prevent water contamination during pesticide application. This method isolates the water source, ensuring that the water used for mixing pesticides does not come into contact with any potentially contaminated water bodies or sources. By using a separate tank, the risk of accidental spillage or runoff into nearby water bodies is significantly minimized, promoting environmental safety.

In contrast, filling from a location near water bodies raises the risk of pesticides inadvertently entering those bodies of water, which can have harmful ecological effects. Submerging the filler hose in water could lead to back-siphoning, where pesticides are drawn back into the water source, leading to contamination. Similarly, using open water sources for filling sprayers is unsafe as it exposes the pesticide mixture to external contaminants and poses a high risk of environmental pollution. Thus, using a separate water tank stands out as the most effective strategy for safeguarding against water contamination during pesticide application.