BAT BAT Water System Hydraulics & Pressure Principles 2

Question 1

What is the significance of 'relief valve opening pressure' in an RPZ assembly test?

Accepted Answer

It verifies the relief valve opens before the first check differential drops below 2 psi

Answer

It confirms the first check valve is tight

Answer

It measures total flow through the assembly

Answer

It indicates the assembly needs replacement immediately

Question 2

What primarily causes water hammer in a piping system?

Accepted Answer

Sudden stoppage or change in flow velocity

Answer

Pipes that are too large in diameter

Answer

Excessive pipe insulation

Answer

Low static pressure in the supply main

Question 3

What is the primary hydraulic function of a check valve within a backflow prevention assembly?

Accepted Answer

Allow flow in only one direction to prevent reversal

Answer

Regulate flow rate through the assembly

Answer

Reduce pressure to safe downstream levels

Answer

Filter sediment from the water supply

Question 4

What unit is water pressure most commonly measured in during backflow field testing in the US?

Accepted Answer

Pounds per square inch (psi)

Answer

Atmospheres (atm)

Answer

Newtons per square meter (N/m²)

Answer

Millimeters of mercury (mmHg)

Question 5

What does increasing pipe diameter do to water velocity when flow rate remains constant?

Accepted Answer

Velocity decreases

Answer

Velocity increases

Answer

Velocity remains the same

Answer

Velocity becomes turbulent

Question 6

What causes 'residual pressure' to drop in a water distribution system during peak demand?

Accepted Answer

Friction losses and increased flow demand drawing down system pressure

Answer

Temperature rise in the mains

Answer

Backflow prevention assemblies restricting upstream flow

Answer

Air pockets accumulating at high points