A hill station in Himachal Pradesh may soon set the bar for clean air in India. The National Physical Laboratory, a Council of Scientific and Industrial Research organisation, best known for the being the repository of physical standards such as the kilogram, second and the centimetre, has set up instruments in Palampur that will measure atmospheric levels of a wide range of pollutants including ozone, nitrous oxides, ammonia and particulate matter.
Based on at least a year’s worth of observations on how these gases vary and the influence of local weather, the scientists hope to develop a reference standard for air quality — realistic to India’s climate — that can be extrapolated to other cities and regions. Delhi’s air is considered among the most noxious in the world though there is wide disagreement on the extent to which Delhi’s vehicles, topography or agricultural practices in neighbouring States are responsible.
Earlier this month, The Hindu reported a study that argued that even if Delhi were to adopt the most stringent emission standards and exhort neighbouring States to follow suit, it would at best halve Delhi’s emissions and wouldn’t bring it globally-accepted safe levels. Delhi’s particulate matter pollution hovers between 300 and 900 microgram/cubic metre, depending on the weather, which is way above the safe level of 40 microgram/cubic metre.
Revised measures
The Central Pollution Control Board has prescribed guidelines for the maximum permissible levels of 12 gases and pollutants, depending on residential, rural or industrial locations. Standards for PM2.5 were laid out in 2009 though it is now mooting a proposal to revise these standards, according to a senior official in the organisation. “Having a background level could mean a new set of air quality standards…or different standards for various regions of the country depending on their local weather conditions,” said Chhemendra Sharma, a senior NPL scientist closely involved with the air quality monitoring project. The NPL has also developed a custom air sampler that claims to measure PM2.5 levels far quicker than current devices available in the market.
