Question

A group of scientists at a meteorological department investigated the deteriorating air quality in the city. They collected random air samples from different areas of the city to find out the reasons for bad air quality.

1. Name any two air pollutants which would be present in the air samples collected by the scientists. [1]
2. What should be the frequency of collecting air samples? [1]

Answer 1

1. • Particulate Matter (PM_2.5 or PM₁₀): Fine dust and smoke particles often generated by vehicular exhaust, construction dust, and industrial activities.
   • Nitrogen Dioxide (NO₂) or Sulphur Dioxide (SO₂): Toxic gases emitted by motor vehicles and industrial facilities.
2. According to standard monitoring guidelines, air samples should be collected for 24 hours at least twice a week (or roughly 104 samples a year) to ensure statistically reliable averages for air quality assessment.