Record high API recorded in Hong Kong
On 22 March, Air Pollution Index reached a record high of 500 since 1995. According to Environmental Protection Department, the high levels of Respirable Suspended Particulates, the contributing pollutant, were partly caused by a sandstorm in northern China, which has been moving south. It seems that a pre-alert system is necessary to warn the Hong Kong residents in advance of any sandstorm attack in the future.