Texas Pesticide Applicator Practice Exam

What type of device prevents the spray mixture in the tank from escaping back through the hose into a water source?

1. Backflow preventer

2. Antisiphoning device

3. Flow regulator

4. Pressure gauge

The correct answer is: Antisiphoning device

The correct choice is an antisiphoning device. This device is specifically designed to prevent backflow, which occurs when there is a drop in pressure in the system, allowing contaminated water from the spray mixture in the tank to flow back into the water source. By maintaining a higher pressure in the hose compared to the water source, the antisiphoning device creates a barrier that stops any potential reversal of flow, thereby protecting the water supply from contamination. While a backflow preventer also serves a similar purpose by ensuring that liquids cannot flow backward into the potable water supply, the term "antisiphoning device" is more directly associated with the spray application systems, specifically addressing the siphoning effect. Flow regulators control the rate of flow in the system and pressure gauges measure the pressure in the system but do not prevent backflow. Therefore, the antisiphoning device is the most accurate answer regarding the prevention of backflow in pesticide application systems.