Colour associated thermal perception : manifeststion and contributing factors with reference to red and blue

Theory of colour, a long-established tradition of artists, differentiates between warm and cool colours. The lack of scientific and statistically substantiated knowledge on aforesaid colour associated thermal perception (CTP) deems to hinder its optimum integration in built environment. Current investigation seeks scientific explanation on manifestation and contributing factors of CTP with reference to a warm colour (red) and a cool colour (blue). Hypothesised potentials of CTP to manifest as a psychological response, a biological response altering core body temperature or an actual thermal sensation caused due to heat radiation emitted via coloured surfaces were tested. A crossover experiment was executed with a sample of healthy, normal sighted, male undergraduates (n=111) selected via stratified simple random sampling (age 19 – 30) using two colour workstations (red and blue) under controlled laboratory conditions. CTP was rated in a 5- point Likert scale while the induced feelings, emotions and preference to each colour treatment were recorded via a questionnaire survey. Temporal artery temperature (TAT) of subjects and the surface temperature of work stations (SFT) were recorded through infrared thermal monitoring. Substantiating colour theory, subjects demonstrated a propensity to perceive red as warm/hot (64.2%) and blue as cool/cold (59.3%). As revealed by logistic regression, CTP neither manifests due to a fluctuation in core body temperature nor as an actual thermal sensation. CTP is a psychological response characterised by common as well as colour specific factors. CTP of both red (RTP) and blue (BTP) are statistically explained by the psychological state induced by each colour, pre-conceived learnt ideas influenced by education, and subjects’ preference. One’s favourite colour and religion are found to influence RTP while age and surface temperature of the applied colour are revealed to influence BTP. Integration of CTP in built environment to psychologically manipulate the perceived thermal environment against the actual thermal condition to achieve the desirable thermal milieu is highly recommended