THERMAL COMFORT AT PLAYGROUNDS: CREATING SAFE OUTDOOR SPACES FOR CHILDREN (PILOT STUDY)

Abstract

As a tropical country, Singapore is exposed to large amounts of solar irradiance, which affects the thermal comfort of outdoor environments. Acknowledging that children are highly susceptible to heat stress yet often neglected in the field of thermal comfort studies, this study aims to investigate thermal comfort at playgrounds by analysing microclimate parameters and playground surface temperatures. On-site microclimate measurements and infrared thermal images were collected at four playgrounds in Clementi town, using the Kestrel Heat Stress Tracker and FLIR i7 camera from August to December 2017 respectively, over a period of 24 days between 1600-1830hrs. Average surface temperatures were then obtained from the thermal images, while microclimate parameters served as inputs for the wet bulb globe temperature (WBGT), a thermal comfort index. Analysis of microclimate variables revealed that shading mechanisms helped to improve thermal comfort, as shaded sites had a lower WBGT than exposed sites. The shade effect was also found to vary between artificial and natural shade, which highlights the need to account for site orientation and sun angle when utilising artificial shade devices. Analysis of surface temperatures of playground floorings and equipment revealed that surface temperatures were dependent on sun exposure and material type. Rubber and sand, two common types of flooring material, were compared, but no significant differences were found. Plastic materials also recorded the highest average surface temperature when compared to metal and rope materials. Without definitive burn thresholds, it is difficult to firmly conclude that playgrounds are thermally safe. However, recurring occurrences of high surface temperatures and high WBGT values emphasise the need for bioclimatic design at playgrounds to improve thermal comfort and safety, so that children can continue to thrive and play in outdoor environments.