Which statement about backflow prevention devices is true?

Which statement about backflow prevention devices is true?

• A. To prevent contaminants from entering potable water by stopping reverse flow
• B. To increase water pressure
• C. To filter air in HVAC
• D. To separate potable water from chemical storage

Answer: (A)

Backflow prevention devices are designed to protect drinking water by stopping reverse flow that could pull contaminants back into the supply. They create a one-way path for water, using mechanisms like check valves, air gaps, or more complex assemblies, so water only moves toward the consumer and cannot flow backward into the public supply. This protects the potable water system from cross-connections with sources that could introduce pollutants. The true statement describes this protective role: preventing contaminants from entering potable water by stopping reverse flow. The other options miss the fundamental purpose—these devices don’t purposefully increase water pressure, they don’t filter air in HVAC systems, and while they help keep potable water separate from potential contaminant sources, their core function is preventing backflow and cross-connection contamination.

Backflow prevention devices are designed to protect drinking water by stopping reverse flow that could pull contaminants back into the supply. They create a one-way path for water, using mechanisms like check valves, air gaps, or more complex assemblies, so water only moves toward the consumer and cannot flow backward into the public supply. This protects the potable water system from cross-connections with sources that could introduce pollutants.

The true statement describes this protective role: preventing contaminants from entering potable water by stopping reverse flow. The other options miss the fundamental purpose—these devices don’t purposefully increase water pressure, they don’t filter air in HVAC systems, and while they help keep potable water separate from potential contaminant sources, their core function is preventing backflow and cross-connection contamination.