Here's the silver lining on B'lore's pollution cloud

Here's the silver lining on B'lore's pollution cloud

Bosky Khanna. Bangalore

Here is one reason why Bus Day should occur not once a month, but right through the year, every day. Statistics obtained from the Karnataka State Pollution Control Board (KSPCB) show that there is a marked reduction in pollution levels on Bus Day. On both February 4 and March 4, there were lower levels of particulate suspended matter and other pollutants in city air, tested at different points.
KSPCB chairman AS Sadashivaiah would like to err on the side of caution. He warns that there is inadequate data to draw conclusions on consistent patterns. The pollution levels are monitored at different locations in the city, so comparisons across these different sites do not reveal much about pollution levels at different points of time, he says. Air pollution levels depend on multiple factors – dust levels, ongoing construction work, the nature of the area surrounding the location where the pollution level is monitored, whether it is residential or commercial, and the density of the population. More data and systematic studies are necessary before conclusions on the patterns of pollution can be established, Sadashivaiah points out.
KSPCB data shows that the levels of respirable suspended particulate matter (RSPM) on February 4, when the Bus Day was observed for the first time, at Marathahalli (Old Airport Road) was 110 micrograms per metre cube (MPMC), while on March 4, at Bannerghatta Road, it was 96 MPMC. The standard value of RSPM is 100 MPMC.
Pollution Control Board data also shows significant reduction in carbon monoxide levels at sites where pollution was monitored on Bus Day. CO2 levels fell by 12.73% on March 4. Although that is a note-worthy reduction, there is need for more data to corroborate the inference that the reduction in CO2 can be attributed to Bus Day.
What is significant is that the data also indicates a sharp increase in pollution levels on the day after the Bus Day, showing that there is indeed a link between lower levels of pollutants in the air and the mode of transport. "It is good that the encouragement to ride the bus is fast becoming a regular feature," said Sadashivaiah, cautiously optimistic about the reduction of air pollution in the city.