1. As per IS 10500:2012, for drinking water in the absence of alternate source of water, the permissible limits for chloride and sulphate, in mg/L, respectively are _____.
[A] 200 and 250
[B] 500 and 1000
[C] 1000 and 400
[D] 250 and 200
Answer: Option C
2. A single rapid test to determine the pollution status of river water is _____.
[A] chemical oxygen demand
[B] dissolved oxygen
[C] total organic solids
[D] biochemical oxygen demand
Answer: Option B
3. In an atmosphere under super-adiabatic lapse rate conditions, the emission from a chimney produces a plume described as _____.
[A] Lofting
[B] Fumigation
[C] Coning
[D] Looping
Answer: Option D
4. ‘Air binding’ may occur in _____.
[A] Aerator
[B] Filter
[C] Sewers
[D] Artesian well
Answer: Option B
5. Which of the following operational problems is not related to the functioning of a rapid gravity filter?
[A] Negative head
[B] Sludge bulking
[C] Mud balls
[D] Incrustation of media
Answer: Option B