What is the purpose of maintaining an air gap between the pesticide solution and the water supply line?

Maintaining an air gap between the pesticide solution and the water supply line is crucial for preventing back-siphoning. This air gap acts as a physical barrier that inhibits the potential for the pesticide solution to flow back into the potable water supply, which could pose severe health risks and contamination issues. By ensuring this separation, any pressure changes or fluctuations in the water system can’t create a vacuum effect that pulls the pesticide back into the supply line. This is in accordance with safe practices and regulations designed to protect public health and the environment, making it an essential protocol in pesticide application.

The other options may outline aspects of pesticide application or usage but do not address the critical safety rationale of preventing cross-contamination that the air gap provides.