The air pollution in Hong Kong on Monday morning was five times worse than in Beijing, according to the World Air Quality Index Project Team.

The Air Quality Index shows air pollution level in Hong Kong at an “unhealthy” score of 192, compared to a score of 34 recorded in Beijing, categorised as “good.”

Kowloon City at 10:25am Monday. Photo: Hong Kong Observatory Webcam.

Hong Kong’s air pollution health index on Monday ranged from moderate to “very high” for general monitoring stations located in 13 districts in the territory, according to the Environmental Protection Department.

Three roadside stations in Central, Causeway Bay and Mong Kok also indicated a “very high” health risk.

The general public is advised to avoid staying outdoors, especially in areas with heavy traffic.

The department forecast a moderate-to-serious health risk for Monday afternoon, but the risk is expected to be reduced to low or moderate by Tuesday morning.

Images captured by the Hong Kong Observatory showed low visibility owing to dense smog.

View from the Peak at 10:25am Monday. Photo: Hong Kong Observatory Webcam.

The PM2.5 level on Monday ranged from 63 micrograms per cubic metre to as high as 152, according to the Hedley Environmental Index managed by the School of Public Health at the University of Hong Kong.

PM2.5 is a measure of the density of hazardous particulate in the air. The World Health Organization daily PM2.5 limit is 25 micrograms per cubic metre.

PM 2.5 level on Monday at 11:21am. Photo: Hedley Environmental Index, HKU.

Earlier this month, the Beijing Municipal Environmental Protection Bureau said the city saw the best air quality since pollution control measures were implemented five years ago.

Local authorities took measures such as banning coal-fired boilers, phasing out cars with high emission and shutting down plants and manufacturing companies over the past five years.

Correction 9.4.18: The Hedley Environmental Index is managed by the School of Public Health at the University of Hong Kong, not the Chinese University of Hong Kong.

Ellie Ng

Ellie Ng has written for Foreign Policy, the Daily Telegraph, Global Voices Online and others.