As the city celebrated Deepavali on Wednesday, few among those merrily bursting fire crackers would have realised that air pollution rose to unusually high levels, noise exceeded permissible limits and thick smog shrouded residential areas and roads.

Respirable suspended particulate matter (RSPM) touched 1423 microgram/cubic metre at Arumbakkam. The permissible limit is 100 microgram/cubic metre.