Roadside pollution in Hong Kong hit hazardous levels on Friday as pollutants emitted from vehicles rose during the stagnant weather.
Readings at roadside monitoring stations in Central, Causeway Bay and Mong Kok hit levels of 183, 193 and 137, respectively on Friday morning.
When a reading hits 100, classified as a “very high” level, people with heart or respiratory illnesses might experience a mild aggravation of their conditions, the Environmental Department said.
A reading of above 200 is a “severe” level of pollution and that the general public was advised to avoid prolonged stays at roadsides with heavy traffic or surrounded by tall buildings. They should also reduce physical exertion in such areas.
Since late Wednesday, the air pollution index recorded in the three roadside stations had been rising gradually from slightly below 100.
A spokesman for the department said the wind had been too stagnant in the past few days to disperse pollutants emitted by vehicles emissions.
He said the air pollution index would remain at very high levels over the weekend.
“According to the Hong Kong Observatory, the weather will continue to be calm in the next few days,” the spokesman said.
The department advised people with heart or respiratory illnesses, and the elderly and children to reduce physical exertion and outdoor activities, and avoid prolonged stays in streets with heavy traffic.