Characterization of Indoor Air Pollutants in Singapore Child Care Centres in Different Ventilation Modes

摘要

Approximately one hundred thousand Singapore children (age group between 2-6 years) spend a large proportion of their active time in child-care centres (CCCs) where their exposure to various indoor pollutants during critical periods of their development is of interests. This study examined three representative CCCs in Singapore, involving three major modes of ventilation: naturally ventilated (NV), split air-conditioning (SAC), and centralized air-conditioning and mechanically ventilated (ACMV). Volatile organic chemicals (VOCs), several phthalate esters (semi-volatile organic chemicals (SVOCs)) were measured simultaneously inside and outside of CCC microenvironments along with their air exchange rates (AERs). Indoor-to-outdoor (I/O) concentration ratios indicated that indoor sources were the main contributors to indoor concentrations for the majority of compounds. Indoor VOCs associated with indoor sources were lower in NV CCC than air-conditioning CCCs (ACMV and SAC) but no such pattern can be observed for phthalates indoor concentration.