2017 Research Report
Monitoring Personal Exposure to PM2.5

In June 2017, Civic Exchange published a report on “Monitoring Personal Exposure to PM2.5 in Hong Kong with Next Generation Sensors.” To download the report, click on the above PDF icon.
You can also watch Dr Zhi Ning and Mr Simon Ng present their findings in the below video.
Key Findings
- Our volunteers’ PM2.5 exposure were generally much higher than readings by the nearest government air monitoring station. Hong Kong may be significantly underestimating its residents’ true pollution exposure risk.
- Our volunteers’ PM2.5 exposure during commuting exceeded limits set by the World Health Organization (WHO). However, they fell within Hong Kong’s own Air Quality Objectives, which are more less stringent.
- Time at home made up about half of the volunteers’ time over a 24-hour period, and reached 81% during weekends. In total, the volunteers in this study spent more than 85% of their time indoors – including at home, at work, and other indoor environments.
- PM2.5 exposure at home was significantly higher than in the office, and even slightly higher than on transportation.
- Pedestrians, in particular, were consistently exposed to about double the WHO’s recommended limit of PM2.5 exposure.
RECOMMENDATIONS
- The Government should inform the public on pollution management in households, given the high level of PM2.5. In May 2017, the Environmental Protection Bureau launched a series of Cantonese, Putonghua and English videos on the issue, which Civic Exchange welcomes as a good first step.
- Hong Kong’s official Air Quality Objectives should be tightened to meet WHO standards.
- More studies should be conducted on individual pollutant exposure, using a much larger and more varied body of volunteers than this initial pilot study.
- New generation sensors should be developed into something smaller, lighter, and capable of providing real-time or personalized data to the individual.
Media Coverage:
- RTHK – HK pollution much worse than govt data, says study (08 June 2017)
- Apple Daily – 調查指屋企空氣污染比公司高兩倍 最大元兇係邊個? (08 June 2017)
- InMedia – 新感應器測空氣污染 PM2.5超出世衛標準2倍 (08 June 2017)
- TheNewsLens – 新研究收集香港空氣污染讀數遠高官方 家居PM 2.5勁過辦公室甚至交通工具 (08 June 2017)
- Hong Kong Free Press – Gov’t significantly underestimates Hongkongers’ exposure to pollution, says think tank (09 June 2017)
- Oriental Daily – 港人每日暴露PM2.5 超世衞標準逾倍 (09 June 2017)
- RTHK Radio 3 – People suffering more from poor air than official data suggests (09 June 2017)
- South China Morning Post – There’s no escape from Hong Kong’s choking air even in your home, study reveals (09 June 2017)
- AM730 – PM2.5與室外僅相差1.5微克 室內空氣污染程度高 (09 June 2017)
- The Standard – Survey shows city more polluted than official data suggests (09 June 2017)
- Ming Pao – 研究﹕隨身錄PM2.5 濃度超政府數據 (09 June 2017)
- HKET – 空氣健康指數不反映室內情況 煮食吸煙增加室內PM2.5 (09 June 2017)
- Sky Post – 家居懸浮粒子 恐比交通工具高 (09 June 2017)
- HK01 – 【宅是最好?】家居空氣污染隨時比辦公室、車廂嚴重?(09 June 2017)
- Harbour Times – Do not underestimate indoor pollution exposure, think tank warns (12 June 2017)