On air: Secretary for the Environment Edward Yau says the pollution notification and communication systems will be enhanced.

The air pollution index reading across Hong Kong is gradually reducing, Secretary for the Environment Edward Yau says, adding government departments will strengthen the notification and communication systems.

Speaking to reporters today, Mr Yau said the API readings of about half of the 11 monitoring stations have dropped to 200 or below. If the situation continues to improve, the indices are expected to fall to between 70 and 120 tomorrow.

He noted the Environmental Protection Department and the Hong Kong Observatory will bolster co-operation, particularly on information and data exchange as well as conducting trend analysis.

The two departments, Mr Yau added, will make use of their communication networks with the neighbourhood areas to enhance information gathering and experience sharing with a view to making early notification whenever necessary.

The Environment Bureau will continue to take the lead in terms of inter-departmental co-ordination and will enhance communication with bureaux and departments including the Food & Health and Education Bureaux, and Labour and Leisure & Cultural Services Departments.

Mr Yau hoped the moves will help accelerate the notification and response time, as well as making proper preparations and timely health advisory.

"This is the first time Hong Kong has been extensively hit by a sandstorm. On Sunday night, although it was midnight, when there was a rapid increase in the API readings, we spared no time in informing the public through radio and television. We also sent our professional staff to explain the situation on radio."

The observatory forecast visibility will be rather low with some rain on March 25 due to the influence of a cold front. Visibility will improve in the two days afterwards.