Ambient Air quality Monitoring Guidlines. - Maharashtra Pollution ...

manpower and needs to be calibrated very frequently depending upon how often the
calibration parameters change. Measurement of Sulphur dioxide (SO2), and
Nitrogen dioxide (NO2) by wet chemical method is fairly simple and can be employed
easily in India. High Volume Sampler is being widely used for particulate matter
measurement in India. Measurement method of SO2, NO2, RSPM, SPM, CO, ozone is
given in Annexure –II.
The following precautions must be followed in analysis of air pollutants
1. Properly clean glassware must be used.
2. One set of glassware must be calibrated as per requirement
3. All critical chemicals used must be of analytical grade
4. Double distilled or nanopure water must be used for preparation of reagents and
analysis.
5. Glassware and storage bottles must be rinsed with distilled water and chemicals
respectively.
6. Reagent bottles must be properly marked by name, strength and date of
preparation, expiry date and initial of chemist who has prepared the reagent.
7. Desiccant in the dessicator must be changed as per requirements
8. The chemicals whose strength changes with time must be standardised before use.
9. Calibration graphs must be made every time a new stock solution is prepared.
10. Reagent bottles must be made air tight before storage.
11. Key reagents must be prepared fresh on the date of analysis.
12. Storage of chemicals must be done as per recommendations like away from sunlight
etc.
13. Active silica gel bottles with holes must be placed inside the weighing chamber.
14. The analytical balance must have a sensitivity of 0.1 mg or better.
4.2.6 Meteorological Measurements
Meteorology plays a significant role in study of air pollution and it is necessary to
measure meteorological parameters. The essential meteorological parameters that
should be measured are wind speed and direction, ambient air temperature, relative
humidity, rainfall, atmospheric pressure and mixing height. Details of the meteorological
instrument and method of measurement is given in Annexure – II. Anemometer is used
to measure velocity of air, wind vane is used to measure wind direction, precipitation
gauge or rain gauge is to measure rainfall and precipitation, thermometer is used to
measure temperature, dry and wet bulb hygrometers, sling psychrometers is used to
measure humidity in the air. SODAR is used to measure mixing height.
The wind data i.e. speed, direction and intensity are graphically represented by a
diagram called wind rose diagram. Humidity is measured in terms of Relative Humidity
which is the percentage of moisture present in the air, complete saturation being taken
as 100. The greater the “RH” more the air is saturated. The RH below 30% is also
unpleasant which can cause, drying of mucous, soar throat and cough. Moisture
indicates the potentiality for fog formation in relation to the degree of air pollution.
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