The air pollution in Hong Kong is two to three times higher than the standard guide recommended by the World Health Organization. Yet air pollution monitoring in Hong Kong is insufficient. During last year’s fire incident at the Amoycan Industrial Centre, the government’s general monitoring station closest to the site recorded the Air Quality Health Index (“AQHI”) as ‘low health risk’, whereas civil society air quality monitoring devices reported a record of air pollutants as high as 1,000 micrograms per square meter (µg/m²). To understand this data gap problem, we invited Mr Loong Tsz Wai, Community Relations Manager of “Clean Air Network”, to give us a talk on 17th February. At this talk entitled “Real Monitoring! Tracking Air Pollution Blackspots District by District”, Loong explained to CarbonCare InnoFest participants how air pollution can be better monitored in Hong Kong.

Medical researches continue to show that air pollution can cause heart stroke and lung cancer, among other diseases. For every increase of ten units in the density of fine suspended particulate matters (known as “PM2.5”), the natural mortality rate is increased by 14%. Health risk caused by air pollution is extremely high to those living in Hong Kong. Professor Anthony Hedley, an academic expert in monitoring air quality, has established the Hedley Index for assessing the air quality of Hong Kong. Yet Prof Hedley himself got sick from the poor air quality of Hong Kong and despite the recuperation he took on the Isle of Man in England, he passed away in 2014.

“Clean Air Network” pointed out that the Environmental Protection Department (EPD) only set up 16 air pollution monitoring stations in Hong Kong. The official monitoring devices, measuring air quality only within a radius of one sq km and generally placed at 11 to 25 meters above ground, can hardly reflect the real condition of the roadside air pollution. As a matter of fact, the density of PM2.5 significantly differs between two blocks on Queen’s Road West. In Mong Kok, the amount of nitrogen dioxide in the air may vary as much as four times in a day. At traffic-congested spots, such as highways and mid-urban districts, the density of nitrogen dioxide exceeds 40 µg/m² in average and it can reach as high as 88 µg/m² in Causeway Bay.

Owing to the poor coverage of official air quality monitoring devices and the unfocused data they collect, the pollution details at district level cannot be accurately measured. In the Amoycan Industrial Centre mini-storage fire incident mentioned above, the AQHI measured by the nearest air quality monitoring station located in Kwun Tong was only 3, a level considered only as ‘low risk’ to health and no corresponding action was required. However, according to “Clean Air Network”, air pollution level in that area was at 1,000 µg/m². We can understand the severity of the situation during the fire if we take Beijing as a reference – air pollution was recorded at 500 to 600 µg/m² during smog days. Besides, those 16 air quality monitoring stations do not cover the situation of the socially vulnerable group, i.e., people living in subdivided flats. According to the survey conducted by “Clean Air Network”, the air pollution level in almost 20 % of the subdivided units doubled that of the general indoor environment. Some inmates of subdivided flats told the interviewers that they often needed to go to church or wander in public libraries, just for some fresh air.

Good quality air should be enjoyed by everybody and it is also up to everyone to support a community-based monitoring scheme. Mr Loong Tsz Wai told the participants that community involvement in citizen science projects was actually very common overseas. Through public engagement, large databases could be established and data could be categorized in finer details with a focus on resolution rather than accuracy. Public action would also drive the government to scale up its anti-pollution policies.  The ‘Air Quality Egg’ project was a successful example from overseas. Participants of this project purchased mini monitoring devices to measure the air quality nearby, and an open platform was available for the public to upload data and store them on icloud for public reference. In Taiwan, there was also an ‘EdiGreen Air Box’ project, jointly developed by local industrialists and Academia Sinica. This project provided air quality monitoring gadgets to schools and the public. To this day, the project has expanded much of its community coverage, with a monitoring device installed almost every few blocks in the city of Taipei. The Taipei municipal government has also joined in and provided support at a later stage.

In the United States, the Environmental Protection Agency teaches students of grade 5 to grade12 how to make air quality monitoring devices by themselves. It is never too late for Hong Kong to start taking action. After Loong’s sharing, the participants divided themselves into several groups and discussed how to promote a community air pollution monitoring scheme in Hong Kong. As participants believed that there was a lack of public awareness, they suggested Hong Kong to follow the example of the US and to start work from education. The academia should be encouraged to develop air quality monitoring devices, which can be creatively applied to large public events such as the marathon, firework displays and cycling tours for promotion purpose.