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

Barometer - The atmospheric pressure at the time of calibration and at the time of
measurement is determined with a barometer. Flow rate corrections are made if,
these two pressures differ by more than 5 kPa (4% of standard 101.3 kPa).
Thermometer - The atmospheric temperature at the time of calibration and at the
time of measurement is determined with a thermometer. Flow rate corrections are
made if, these two temperatures differ by more than 15 o C (5% of standard 298 K).
Class-S Weights - A 3 g standard mass of Class-S or Class-M quality is used to
verify the span of the analytical balance
Analytical Balance - Some analytical balances can be calibrated by the operator
while others require specialized skills to re-calibrate. In general, analytical balances
should be calibrated when first purchased, any time the balance is moved, at least
every twelve months, or whenever an NBS traceable 3.0000 g weight registers
outside + 0.5 mg of its designated weight. At each weighing session a balance
calibration check is performed using a Class S of Class M weight.
(xi) Sample Collection, Transportation and Analysis
Monitoring must be done twice a week for 24 hours so as to have 104 readings in a year.
The results so obtained can be compared with NAAQS. Methods recommended by
CPCB should be followed by all monitoring agencies so that results are comparable.
Sophisticated instruments must be used for monitoring. The data must be reported in
significant figures and must be compiled so that the comparison can be made with the
National Ambient Air Quality Standards (NAAQS).
In case of sampling SO2 and NO2, grease in the impingers must be put and ice must be
kept in ice tray while sampling. The samples must be transported in ice tray so that no
loss of samples occur while in transit. Evaporation losses must be made up by distilled
water.
In case of SPM and RSPM sampling and analysis, pre and post conditioning of filter
paper must be done. The other precautions as given in the previous chapter must be
followed.
(xii) Analytical Quality Control
Analytical quality control must be exercised in the laboratory. Interlaboratory comparison
exercises such as using Ring Test Facility at CPCB must be carried out regularly so that
errors can be corrected.
(xiii) Training of Manpower
Periodic training programmes and workshops must be arranged so that manpower
involved in monitoring are familiarized with proper methods of sampling and analysis. Site
staff must be trained so that they are able to read rotameter, manometer properly, note
down the time and carry out maintenance of blower, change of carbon brush etc. The
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