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Four new air quality measuring instruments will be installed in Puttalam, Anuradhapura, Vavuniya and Jaffna during the coming days, the National Building Research Organization (NBRO) said.
The particulate matter levels in Colombo went up twofold, to unhealthy levels, creating an atmosphere of smog but have come down since.
Air quality started deteriorating from November 5-8 in Colombo, said Climate Scientist cum Environmental Engineer Lareef Zubair.
&The particulate matter levels went up twofold, to unhealthy levels, but has come down since,& he said.