The key objectives of NAMP are:

• To determine the status and trends of ambient air quality in different parts of the country.
• To check whether prescribed ambient air quality standards are violated.
• To identify non-attainment cities, i.e., cities where air quality standards are not met consistently.
• To generate knowledge needed for developing preventive and corrective measures for air pollution control.
• To understand the natural cleansing processes of the environment such as:
  • Pollution dilution.
  • Dispersion by winds.
  • Dry and wet deposition.
  • Chemical transformation of pollutants.

Pollutants and Parameters Monitored

The programme monitors four major air pollutants:

• Sulphur Dioxide (SO₂)
• Oxides of Nitrogen as NO₂
• Respirable Suspended Particulate Matter (RSPM / PM₁₀)
• Fine Particulate Matter (PM₂.₅)

Additionally, meteorological parameters are recorded as they influence air pollution levels:

• Wind speed & direction
• Relative humidity (RH)
• Temperature

Monitoring Methodology

• Duration: Continuous over 24 hours.
• Sampling Frequency:
  • Gaseous pollutants: every 4 hours.
  • Particulate matter (PM₁₀): every 8 hours.
  • PM₂.₅: every 24 hours.
• Conducted twice a week, resulting in 104 observations per year per location.

Monitoring is performed with the support of CPCB, State Pollution Control Boards, Pollution Control Committees, and other designated agencies.

Data Quality and Support

• CPCB ensures uniformity and consistency of data across the country.
• Provides technical and financial assistance to state agencies for operating monitoring stations.
• Involves a large number of personnel and equipment, which may lead to minor variations or biases.
• Therefore, the collected data should be considered indicative rather than absolute.