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Unit 7 The quality of our air. Unit 7. The Quality of Our Air. Unit 7 The quality of our air. How clean is the air?. Air quality and pollutants Polluted air contains a lot of dust particles and acidic gases. They are harmful to our health. Unit 7 The quality of our air.
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Unit 7 The quality of our air Unit 7 The Quality of Our Air
Unit 7 The quality of our air How clean is the air? Air quality and pollutants Polluted air contains a lot of dust particles and acidic gases. They are harmful to our health.
Unit 7 The quality of our air What is ‘air pollution index’? The Environmental Protection Department operates a network of air quality monitoring stations to measure the air quality of various districts. Internet Air quality monitoring station
Tai Po Yuen Long Tsuen Wan Shatin Kwai Chung Roadside Station in Causeway Bay (Source: EPD) Shamshuipo Mongkok Kwun Tong Causeway Bay Central/ Western Eastern Central Ambient Station Ambient Station in Tsuen Wan (Source: EPD) Roadside Station km N Unit 7 The quality of our air The location of air quality monitoring stations
Smoky vehicles The lorry took part in a trial to test heavy vehicles using the treadmill. Smoky vehicles will have to undergo tests Unit 7 The quality of our air What is ‘air pollution index’? The department also sets up roadside monitoring stations to find out the level of pollution in busy streets and roads.
Unit 7 The quality of our air What is ‘air pollution index’? The air pollution index increases as the air quality gets poorer. An index under 50 is regarded as good while that over 100 is regarded as unhealthy. The department publishes an air pollution index each day. The index gives advice to the public about what people should do when the air reaches an unhealthy level. The index has a range of 0 to 500 and is divided into five bands.
Reduce physical and outdoor activities API Action to Take Air Pollution Level Severe Persons with heart or respiratory illness should reduce physical and outdoor activities. Very high No immediate response action required. High No action required. Medium No action required. Low Unit 7 The quality of our air What is ‘air pollution index’?
Unit 7 The quality of our air What is ‘air pollution index’? Air pollution index are calculated by comparing the measured concentrations of the major air pollutants with their respective health related Air Quality Objectives (AQOs) established under the Air Pollution Control Ordinance. These pollutants are nitrogen dioxide, sulphur dioxide, ozone, carbon monoxide and respirable suspended particulates. APIs for each of these five pollutants are calculated and the highest API number is reported as the API of that hour.
% Air quality Good Moderate Unhealthy Month Unit 7 The quality of our air Monthly air quality of 1996
% Air quality Good Moderate Unhealthy Month Unit 7 The quality of our air Discussion Do you know why air quality is often good in summer but getting worse in winter?
Unit 7 The quality of our air Terms to learn Convention (會議)--a meeting held to discuss a particular matter. Greenhouse gases (溫室氣體)--gases such as carbon dioxide which trap the sun’s heat and cause the world temperature to rise. Air pollution index (空氣污染指數)--an indicator published by the Environmental Protection Department to show air quality.