The maximum acceptable noise level in offices is
A.10 dB
B.40 dB
C.75 dB
D.100 dB
Category: Environmental Engineering Mcqs
For the maximum alkalinity of water, the pH value would be
A.Zero
B.7
C.8
D.14
E.20
The unit parts per million is identical to
A.Grains per galleon
B.Pounds per cubic foot
C.Milligrams per kg
D.Tonnes peracre foot
For the maximum acidity of water, pH value would be
A.0.01
B.0.1
C.1
D.10
E.11
Swimming pool water requires
A.pre-chlorination
B.super-chlorination
C.dual-chlorination
D.de-chlorination
Ultra-violet rays are used for the treatment of water known as
A.Dechlorination
B.Disinfection
C.Aeration
D.Filtration
E.Bleaching
The permissible hardness of water for public supplies is
A.10 mg/litre
B.25 mg/litre
C.75 mg/litre
D.115 mg/litre
E.400 mg/litre
The chloride content in the water for public supplies should not exceed
A.250 mg/litre
B.100 mg/litre
C.50 mg/litre
D.20 mg/litre
E.1 mg/litre
The bactericidal, virucidal and cysticidal efficiency of chlorine as a disinfectant
A.increases with a decrease in pH
B.increases with a increase in pH
C.decreases with a decrease in pH
D.decreases with an increase in pH
Prechlorination
A.Improves coagulation
B.Reduces odours
C.Reduces organisms
D.All of the above
E.None of the above
