Indoor air quality in substandard housing in Hong Kong. (July 2019)

• Record Type: Journal Article
• Authors: Cheung, Pui Kwan; Jim, C.Y.
• Is Part Of: Sustainable cities and society. Volume 48(2019)
• Publication Date: 2019-07
• Subjects: Substandard housing -- Inadequate ventilation -- Indoor air quality -- Open-plan cooking -- Air conditioning use -- Health impact; Sustainable urban development -- Periodicals; Sustainable buildings -- Periodicals; Urban ecology (Sociology) -- Periodicals; 307.76
• DOI: 10.1016/j.scs.2019.101583
• Languages: English
• ISSNs: 2210-6707

Abstract

Highlights: CO, CO2, PM10, PM2.5 and VOCs were monitored for 48 h in substandard housing units. Mean concentrations were viz. 367 μg/m 3, 1216 mg/m 3, 22 μg/m 3, 14 μg/m 3 & 794 μg/m 3 . No significant correlation was found between indoor and outdoor CO, PM10 and PM2.5. Open-plan cooking exposed all occupants to high levels of PM10 and PM2.5. Air conditioning use aggravated ventilation and accelerated CO2 & VOC accumulation. Abstract: Sub-divided unit (SDU) provides substandard housing in Hong Kong by partitioning a small flat into several tiny units. With typical floor area of merely 9.3 m 2, they often lack a partitioned kitchen. About 210, 000 persons (2.9% of Hong Kong's population) are living in 92, 700 SDUs. Inserting extra partitions significantly suppress ventilation which was pushed below building standards to degrade indoor air quality (IAQ). This study monitored the concentrations of CO, CO2, PM10, PM2.5 and VOCs in eight typical SDUs for 48 h. The mean concentrations were 367 μg/m 3, 1216 mg/m 3, 22 μg/m 3, 14 μg/m 3 and 794 μg/m 3 respectively. PM10 and VOC concentrations exceeded Hong Kong IAQ objectives (excellent class) by 1.10 and 3.89 times respectively. Indoor and outdoor CO, PM10 and PM2.5 concentrations had no significant correlation. Cooking and air conditioning use notably controlled IAQ. During open-plan cooking, spread of fumes pushed maximum PM10 and PM2.5 concentrations to exceed 1000 and 500 μg/m 3 respectively to threaten the health of occupants especially children. CO2 and VOCs rapidly accumulated during AC use, reaching over 3000 mg/m 3 and 2000 μg/m 3 respectively. Timely interventions are needed to reduce impacts on tenant's health and provide healthy affordable housing to low-income families.