Why should the pipe tanking water from a roof supply tank extend at least six inches above the bottom of the tank?

• A. To prevent overflow
• B. To avoid contamination
• C. To prevent sediment from entering the plumbing
• D. To maintain water pressure

Answer: (C)

The requirement for the pipe tanking water from a roof supply tank to extend at least six inches above the bottom of the tank serves to prevent sediment from entering the plumbing system. Tanks often accumulate sediments, debris, and other particulates that can settle at the bottom. By ensuring that the outlet pipe is raised above this sediment accumulation, the design effectively minimizes the risk of these unwanted materials being drawn into the plumbing. This is crucial for maintaining water quality and ensuring that the water delivered through the plumbing system is clean and safe for use.

While overflow prevention, contamination avoidance, and maintaining water pressure are important considerations in tank design and plumbing systems, they do not specifically address the need to keep sediment out of the water supply. Contamination can be controlled through other means, like proper tank maintenance and filtration systems, and overflow management typically involves mechanisms to handle excess water rather than the positioning of the outlet. Similarly, while proper pressure is important, it typically relates more to system design than the specific placement of outlet pipes in relation to sediment accumulation.