Lagooning process is mainly a means of the__________________?

A. Sludge disposal
B. Reduction of excessive flow in sewers
C. Biological treatment of wastes
D. None of these

Siderosis is a disease caused by the inhalation of ______________ dust?

A. Coal
B. Silica
C. Iron
D. None of these

Noise level heard inside a bus in busy city traffic or inside a sub-way train corresponds to about ______________ decibels?

A. 75
B. 95
C. 120
D. 140

A gas is termed as non-toxic, if its maximum permissible concentration (TLV) ranges from ______________ ppm?

A. 1000 to 2000
B. 3000 to 6000
C. 6000 to 9000
D. 10000 to 100000

‘Pneumoconiosis’ is a disease caused by the inhalation of ______________ dust?

A. Coal
B. Uranium ore
C. Iron ore
D. Lime

COD of raw municipal sewage may be in the range of about _____________ mg/litre?

A. 1-2
B. 5-10
C. 90-120
D. 1500-2500

Maximum permissible limit of industrial noise as recommended by World Health Organisation (WHO) is _____________ decibels?

A. 35
B. 75
C. 95
D. 105

Exposure to chemicals having carcinogenic properties cause ____________________?

A. Dermatitis (skin disorder)
B. Cancer
C. Asphyxiation (suffocation)
D. Asthma

World’s worst radioactive pollution was caused by nuclear reactor disaster which occured in ___________________?

A. Arizona (U.S.A.)
B. Chernobyl (undivided U.S.S.R.)
C. Pennsylvania (U.S.A.)
D. Moscow (U.S.S.R.)

High noise level in a chemical plant can be controlled by the_________________?

A. Suppression of noise at the source itself
B. Path control of noise
C. Protection of operating personnel
D. All A., B. & C.