Consider the following statements regarding a good building/house drainage system : 1. The pipes should be of non-absorbent materials. 2. The system should have traps at all necessary points. 3. The branch drains should be as long as possible. Which of the above statements are correct ?
- A1 and 2 onlyCorrect
- B2 and 3 only
- C1 and 3 only
- D1, 2 and 3
Solution
Concept
Requirements of a house drainage system
Step-by-step solution
1. Pipes must be non-absorbent so that sewage does not seep out (true). 2. Traps are needed at fixtures to keep sewer gas out (true). 3. Branch drains should be as SHORT as possible, with few bends (false).
Explanation
Short, straight branches reduce the chance of choking and the cost.
Why the other options are wrong
Statement 3 is the opposite of good practice.
Shortcut
Drains: non-absorbent, trapped, short.
Common mistake
Accepting long branch drains.
Correct answer: A) 1 and 2 only