Civil Engineering - UPSC Civil Service Exam Questions - Discussion

Discussion Forum : UPSC Civil Service Exam Questions - Section 11 (Q.No. 44)

UPSC Civil Service Exam Questions

44.

Consider the following statements :
Ventilation of sewer lines is necessary to
1. avoid building up to sewer gases.
2. ensure atmospheric pressure in the waste water surface.
3. ensure the safety of sewer maintenance people.
4. provide oxidation facility to sewage.
Which of these statements are correct ?

1, 2 and 4

1, 3 and 4

2, 3 and 4

1, 2 and 3