When Bangalore Metropolitan Transport Corporation (BMTC) buses went off the city roads on September 13 and 14, the levels of air pollution witnessed a steep increase, particularly with regard to sulphur dioxide (SO) and nitrogen dioxide (NO).
The Karnataka State Pollution Control Board (KSPCB) which continuously monitors ambient air quality at its stations located near the Bangalore City Railway Station and Saneguruvanahalli, off Basaveshwaranagar, has said that levels of SO and NO increased by 33 per cent and 27 per cent respectively, on the second day of the strike when compared to normal days near the Bangalore City Railway Station.
This is because more number of two-wheelers and four-wheelers running on petrol came out on the roads, according to a senior official with the board.
However, the levels of carbon monoxide (CO) and Respirable Suspended Particulate Matter (RSPM) decreased marginally, by 5 per cent and 3 per cent respectively, on the second day of the strike.
This marginal reduction was despite over 6,000 BMTC buses being off the roads, the official said.
On the first day of the strike, the levels of all the four parameters of air pollution — SO, NO, CO and RSPM, witnessed 14 per cent, six per cent, nine per cent and 27 per cent decrease compared to a normal day.
This could mainly be due to heavy showers the city received on the night of September 13, according to the official.