Central worst affected as pollution soars
Regina Leung SCMP
Updated on Dec 07, 2007
Pollution, trapped by light winds and hot weather, is expected to remain until wind speeds pick up later in the week.
Smoggy weather and light wind ushered the air pollution index (API) to over 100 in several areas of Hong Kong on Friday, including Central, Causeway Bay and Mong Kok.
Based on roadside station readings, Central recorded the highest API level of 145, compared to 133 in Causeway Bay and 122 in Mongkok.
In the general station readings, Yuen Long, Tung Chung, Tai Po, Central and Western districts also recorded API levels over 100.
Pollutants are trapped under the light wind, and the smoggy conditions favour the photo-chemical formation of ozone in the region, resulting in elevated ozone levels, a spokesman at the environmental department said.
When the level passes 100, the environmental department says people with heart or respiratory illnesses should avoid prolonged stays in areas with heavy traffic. Those who must travel to such congested areas are advised to reduce physical activity.