List of top Air and Noise Pollution Questions asked in GATE ES

The concentration of chemical A in ambient air is 50 \(\mu g/m^3\) and the toxicological index limit for a threshold health effect for this chemical is 5 mg.

If the average breathing rate is 4 L/min, the minimum time of exposure that can lead to any health effect is ______ days (rounded off to one decimal place).
Which ONE of the following options CORRECTLY matches the Criteria Air Pollutants with measurement methods used in Continuous Ambient Air Quality Monitoring Stations (CAAQMS) operated by Central Pollution Control Board (CPCB) given in the table?
Criteria Air PollutantsMeasurement Methods
(P) Sulphur Dioxide (SO2, in µg/m3)(i) Chemiluminescence
(Q) Nitrogen Dioxide (NO2, in µg/m3)(ii) Non Dispersive Infra Red (NDIR) spectroscopy
(R) Particulate Matter (PM2.5, in µg/m3)(iii) Ultraviolet fluorescence
(S) Carbon Monoxide (CO, in mg/m3)(iv) Beta attenuation

The mixing ratio of CO2 at a pressure of 1 atm and at 300 K is reported as 340 ppmv.

Considering ideal gas conditions, the equivalent concentration of CO2 in air is ______ mg/m3 (rounded off to two decimal places).

The molecular weight of CO2 = 44 g/mol

Universal gas constant = 8.314 J/mol-K

The general atmospheric composition of gases in the decreasing order is ______.
Which ONE of the following options CORRECTLY matches the atmospheric stability conditions with plume conditions/ behaviours given in the table?
Atmospheric Stability ConditionsPlume Conditions/Behaviours
(P) Strong instability(i) Fanning plume
(Q) Neutral stability(ii) Fumigation
(R) Surface inversion(iii) Coning plume
(S) Aloft inversion(iv) Looping plume
Which of the following are valid assumptions of the Gaussian plume dispersion model used for estimating ground-level pollutant concentrations from a point source?
In a stack emission measurement at an industry, the stack cross-sectional area at 30 m height was divided into four equal sectors. The measured velocities and SO2 concentrations through these sectors at this height are given in the table.
The mean SO2 concentration from the stack is ______ mg/m3 (rounded off to two decimal places).
Sector NumberVelocity (m/s)SO2 Concentration (mg/m3)
1151000
2171150
3191250
4211275
Sound pressure levels were measured at a location over four consecutive 15-minute intervals as 65 dB, 70 dB, 68 dB, and 72 dB. The equivalent continuous sound level (Leq) over the total one-hour period is ______ dB (rounded off to two decimal places).
Which of the following chemical reactions is/are related to smog formation in the troposphere?
The unit used to measure sound intensity level is:
Which air pollutant is mainly responsible for acid rain?