Question 52

The minimum change in elevation permitted for the smallest diameter building sewer serving eight bathrooms is 20 inches.

To adequately serve eight bathrooms in an apartment building, the minimum change in elevation for the smallest diameter building sewer, which is 120 feet long, must be 20 inches.

A) 25 inches

This option exceeds the required minimum change in elevation. While it is possible for a sewer system to function effectively with a greater elevation change, this option does not represent the minimum necessary for the specified conditions.

B) 20 inches

This is the correct answer as it meets the minimum required change in elevation for a 120-foot long building sewer serving eight bathrooms. Compliance with this elevation ensures proper drainage and function of the sewer system.

C) 15 inches

This option falls short of the minimum requirement. A change in elevation of only 15 inches may not provide adequate drainage for the sewer serving eight bathrooms, potentially leading to issues with waste flow and blockages.

D) 10 inches

This option is also insufficient as it does not meet the minimum change in elevation needed for the specified sewer length and number of bathrooms. A 10-inch elevation change could hinder proper drainage and create problems in the sewer system.

Conclusion

The correct answer is 20 inches, as it aligns with the minimum requirements for effective sewer operation in the given context. All other options either exceed or do not meet the necessary elevation change, underscoring the importance of adhering to the specified standards for plumbing systems serving multiple bathrooms.