Behaviour and light: A human-centric study on how choice and shared spaces influence light exposure and wellbeing

Lighting metrics and standards are tested against spaces when designing the built environment, but humans move between different indoor and outdoor spaces throughout their day. This ‘room versus human’ relationship differs between individuals and likely changes how light affects wellbeing between persons even in the same indoor environments during working hours. Understanding this relationship is crucial for optimizing living and working environments. In this paper, we explore the relationship between light exposure and wellbeing of 20 university students using sensors which are wearable and thus detect human light exposure directly. A comprehensive data collection methodology is employed, including data-logging worn spectral irradiance sensors and smartwatch-administered surveys. These tools gather timeseries spectral irradiance data at 1-minute intervals and qualitative data through periodic surveys administered four times daily. The surveys capture participants’ sleep quality, mood, and alertness, alongside daily journals where participants document their activity schedules and locations. This dual collection method aims to provide insights into how varied light exposures—including in shared environments—influence sleep and alertness. Our analysis uses Repeated Measure Correlation (rmcorr) and Pearson correlation to assess the impact of melanopic irradiance on alertness, sleep pattern and quality, considering both individual behaviours and environmental contexts. By analyzing correlations between light exposure, activity patterns and self-reported wellbeing, we aim to elucidate how architectural designs and daily routines influence light exposure and subsequent health outcomes. Findings will contribute to a reevaluation of light exposure standards and student lighting patterns, enhancing the understanding of behavioural choice and lighting’s role in daily life. This study lays the groundwork for future large-scale applications, leading to personalized lighting strategies that promote circadian health within university spaces and homes.