The Department of Environment (DoE) today advised the residents of Dhaka and the surrounding areas to wear face masks while outdoors, as the city's Air Quality Index (AQI) has deteriorated to a "very unhealthy" level.

"Wearing a face mask outdoors is mandatory," said a DoE press release issued today.

The advisory follows a sharp decline in air quality, with the AQI crossing 250 at 10:00am, according to the latest air quality monitoring report.

The DoE also urged sensitive groups, including the elderly, children, and people with health conditions to avoid going outside unless absolutely necessary.

The AQI is fluctuating hourly and air quality in the capital and its nearby areas often ranges from "unhealthy" to "hazardous" during the dry season, the report said.