Mains Practice Questions

Approach

• Start with introducing Global Air Quality Guidelines issued by the World Health organization and write its key points.
• Describe how these guidelines are different from its last update in 2005.
• Discuss changes in India’s National Clean Air Programme required to achieve revised standards.

Answer

The World Health Organisation released an updated version of the Global Air Quality Guidelines (AQGs). The guidelines recommend new air quality levels to protect the health of populations, by reducing levels of key air pollutants. This is the first-ever update of WHO since 2005.

The key updates of the new Global Air Quality Guidelines are

• WHO’s new guidelines recommend air quality levels for six pollutants – particulate matter (PM2.5 & PM10), ozone (O₃), nitrogen dioxide (NO₂), sulphur dioxide (SO₂) and carbon monoxide (CO).
• The annual average for PM2.5 and PM 10 should not exceed 5 micrograms and 15 micrograms per cubic metre of air respectively, while the 24-hour average should not exceed 15 micrograms and 45 micrograms per cubic metre.
• The average levels of ozone, nitrogen oxide, sulphur dioxide and carbon monoxide should not exceed 100 micrograms, 25 micrograms, 40 micrograms, 4 micrograms per cubic metre respectively over a 24-hour period.

The new air quality guidelines mean that entire India would be considered a polluted zone for most of the year. The new WHO norms should push India to work harder to make its air cleaner and safer. The region has challenging meteorological and climatic conditions, with the added challenge of haze columns, heat island effects and exceedingly high base pollution.

India’s National Clean Air Programme (NCAP) aims for a 20% to 30% reduction in particulate matter concentrations by 2024 in 122 cities, keeping 2017 as the base year for the comparison of concentration. India’s air pollution standards are more relaxed in comparison to WHO’s prescribed guidelines. Thus, efforts are needed to make the guidelines more stringent with revised targets. Under the proposed Clean Air for All, the government tends to make targets of PM2.5 & PM10 more stringent. There is a need to adopt an airshed approach to take measures to deal with air pollution.