What special risk do you face when using a hose-end proportioner?

• A. Back-siphonage
• B. Fire hazard
• C. Groundwater contamination
• D. Solar degradation

Answer: (A)

The main issue with hose-end proportioners is back-siphonage. These devices use your water pressure to draw in concentrated pesticide or fertilizer, but if water pressure drops or a downstream valve closes, suction can pull that contaminated liquid back into the household water supply. That backflow can contaminate drinking water, which is a serious safety hazard. To prevent it, use a backflow prevention device (like an anti-siphon/vacuum breaker) and ensure proper installation and shutoff practices. The other options—fire hazard, groundwater contamination from other routes, or solar degradation—aren’t the specific risk inherent to operating a hose-end proportioner in the way back-siphonage is.