Maximum allowable concentration of CO2 in air for safe working is _____________ ppm (parts per million)?

Related Mcqs:

From pollution control point of view, the maximum permissible concentration of sulphur dioxide in atmospheric air is about ________________ ppm?

A. 5 B. 50 C. 500 D. 5000...

The density of the gases (present in air) decreases with increasing altitude to such an extent, that about 70% of the mass of atmospheric air is found in the lower 5 km. of the atmosphere. This lower region of atmosphere is called the_________________?

A. Ionosphere B. Troposphere C. Stratosphere D. None of these...

In sewage treatment, its sedimentation is speeded up by commonly adding__________________?

A. Hydrochloric acid B. Lime C. Copper sulphate D. Sodium sulphate...

Bag filter design is predominantly dependent on gas temperature, as it affects the gas density & viscosity and the selection of filtering material. The pressure drop in a bag filter is__________________?

A. Inversely proportional to viscosity of gas B. Proportional to the viscosity & density of the gas C. Proportional to the pressure of the gas D. Both B. and C....

Presence of ____________ in water stream are deleterious to aquatic life?

A. Soluble and toxic organics B. Suspended solids C. Heavy metals and cyanides D. All A., B. & C....