০০। 'Particulate' air pollutants are finely divided solids and liquids. Which of the following is not a 'particulate' ?
ক) Dust & mists
খ) Smoke & fumes
গ) Photochemical smog & soot
ঘ) None of these
০১। 'Pneumoconiosis' is a disease caused by the inhalation of __________ dust.
ক) coal
খ) uranium ore
গ) iron ore
ঘ) lime
০২। 'Safe limit' called Threshold Limit Value (TLV) of carbon monoxide in atmospheric air is < 50 ppm. The main source of carbon monoxide pollutant in air is the
ক) industrial chimney exhaust.
খ) automobiles exhaust.
গ) photochemical reaction in polluted atmosphere.
ঘ) burning of domestic fuel.
০৩। 5-200 μm size particles are called
ক) colloids or aerosols
খ) powder
গ) dust
ঘ) smoke
০৪। 80% less than 200 mesh size particles are called
ক) smoke
খ) powder
গ) grit
ঘ) aggregates
০৫। A 'body' which allows the short wavelength incoming solar radiation to enter in, but does not allow long wave length outgoing infra red radiation to escape out is called the
ক) global warming
খ) green house
গ) atmospheric effect
ঘ) ionosphere
০৬। A considerable part of the harmful ultraviolet radiation of the sum does not reach the earth surface, because of the fact that, there is a layer of __________ high above earth's atmosphere, which absorbs it.
ক) hydrogen
খ) carbon dioxide
গ) ozone
ঘ) none of these
০৭। A gas is termed as non-toxic, if its maximum permissible concentration (TLV) ranges from __________ ppm.
ক) 1000 to 2000
খ) 3000 to 6000
গ) 6000 to 9000
ঘ) 10000 to 100000
০৮। A man exposed to excessive noise level in the working environment may suffer from
ক) hearing loss
খ) rupture of ear drum
গ) nervousness & fatigue
ঘ) all (a), (b) & (c)
০৯। A masonry structure built below ground level, where biochemical reaction takes place due to anaerobic bacteria is called
ক) cesspool
খ) lagoon
গ) skimming mill
ঘ) septic tank
১০। A shallow pond in which the sewage is retained and biologically treated is called
ক) oxidation
খ) Imhoff tank
গ) lagoon
ঘ) skimming tank
১১। A standard test for determination of hardness in water is termed as __________ test.
ক) EDTA
খ) electometric
গ) total count
ঘ) presumptive
১২। Acute danger to human life (i.e. death) exists, if the concentration of CO2 in atmospheric air exceeds __________ percent (by volume).
ক) 1
খ) 3
গ) 7
ঘ) 20
১৩। Aerobic biological oxidation ponds used for the purification of polluted water
ক) destroys/removes pathogen from the sewage.
খ) is not very effective for nonbiodegradable substances (e.g. ABS) containing effluents.
গ) destroys/removes pathogen much more effectively if the sewage is chlorinated.
ঘ) all (a), (b) & (c).
১৪। Aerodynamic noise resulting from turbulent gas flow is the most prevalent source of valve noise in fluid ilow control. It is caused due to
ক) Reynold stresses
খ) shear forces
গ) both (a) & (b)
ঘ) neither (a) nor (b)
১৫। Aerosols present in atmospheric air may be
ক) positively charged.
খ) negatively charged.
গ) neutral.
ঘ) combination of all (a), (b) & (c).
১৬। Algae growth in water is controlled by
ক) deoxidation
খ) chlorination
গ) bleaching
ঘ) aeration
১৭। Ambient noise level can be reduced by __________ decibels by planting trees (like coconut, neem etc.) near public utility buildings (like hospitals & schools).
ক) 1-2
খ) 5-10
গ) 15-20
ঘ) 25-30
১৮। Arsenic pollutant is not generated in____industries.
ক) tanneries
খ) glass & ceramic
গ) beverages
ঘ) any of these.
১৯। As per the world health organisation (WHO) specification, the maximum permissible concentration (i.e., TLV) of particulate matter in air is __________ μg/m3.(μg-microgram)