A. Hydrogen sulphide (H2S)
B. Carbon dioxide (CO2)
C. Methane (CH4)
D. All the above
Related Mcqs:
- The gas which may cause explosion in sewers, is_________________?
A. Carbondioxide
B. Methane
C. Ammonia
D. Carbon monoxide - For non-scouring velocity 5 m/sec, the type of sewers generally preferred to, is____________________?
A. Cast iron sewers
B. Cement concrete sewers
C. Glazed bricks sewers
D. Stone ware sewers - The drop man holes are generally provided in sewers for____________________?
A. Industrial areas
B. Large town ships
C. Hilly town ships
D. Cities in plains - For trunk and out-fall, the type of sewers generally used, is_____________________?
A. Standard egg shaped
B. Circular shaped
C. Horse shoe shaped
D. Parabolic shaped - The minimum recommended diameter of sewers, is_________________?
A. 5 cm
B. 10 cm
C. 15 cm
D. 20 cm - The gas evolved in sewers is________________?
A. Carbondioxide
B. Hydrogen sulphide
C. Methane
D. All of these - Cement concrete sewers are only suitable if non-scouring velocity is between_________________?
A. 2.5 to 3.0 m/sec
B. 3.0 to 4.0 m/sec
C. 3.5 to 4.5 m/sec
D. 4.5 to 5.5 m/sec - The maximum diameter of sewers adopted in the designs is_______________?
A. 1.0 m
B. 2.0 m
C. 3.0 m
D. 4.0 m - Large diameter sewers subjected to external pressure alone, are reinforced ______________________?
A. Near the inner surface of the pipe
B. Near the outer surface of the pipe
C. Both A. and B.
D. With elliptical cage - The gradient of sewers depends upon_________________?
A. Velocity of flow
B. Diameter of the sewer
C. Discharge
D. All the above
