11.5-200 μm size particles are called
12.80% less than 200 mesh size particles are called
13.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
14.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.
15.A gas is termed as non-toxic, if its maximum permissible concentration (TLV) ranges from _________ ppm.
16.A man exposed to excessive noise level in the working environment may suffer from
17.A masonry structure built below ground level, where biochemical reaction takes place due to anaerobic bacteria is called
18.A shallow pond in which the sewage is retained and biologically treated is called
19.A standard test for determination of hardness in water is termed as _________ test.
20.Acute danger to human life (i.e. death) exists, if the concentration of CO2 in atmospheric air exceeds _________ percent (by volume).