| dc.description.abstract | This research assesses the influence of correlated color temperature (CCT) of
artificial light and the integration with daylighting on academic students’ performance
and sensations, in warm climate in low latitude (5,84 S, 35,20 W). The issue was
motivated by the fact artificial light interferes in person's circadian cycle, which
regulates sleep, alert, appetite, and other conditions. Such biologic clock is related to
the daylight CCT hourly changes, from yellow at sunrise and sunset, to white direct
sunlight and light-blue overcast daylight. The artificial light does not to match the
sun’s own color shifts throughout the day and consequently disturbs the cognitive
performance, attention, visual comfort and wellbeing sense. This research questions
similar effect in low latitude, with abundant daylight availability, acknowledging the
fact the literature regards, majority, light conditions in medium and high latitudes. The
research procedures consist in assessing performance and sensations of volunteers,
academic students, through test and questionnaire, during three periods: morning,
afternoon and evening. Toulouse-Piéron's Test assessed attention and perception,
measuring the speed and accuracy of a simple task. A following questionnaire was
applied in order to quantify the self-declared sensations of lighting comfort, attention,
relaxing and environment comfort, varying from null to five scale. Three different CCT
fluorescent lamps available in the market were tested in a classroom, yellowish white
(3000K, warm), bright white (4000K, neutral), blueish white (6500K, cold), integrated
and non integrated with daylighting during morning and afternoon. The registers were
statistically analyzed using the analysis of variance (ANOVA) and ordinal logistic
regression, identifying morning as the only period influenced by CCT variations. The
comparison among the three periods resulted in a tendency of blueish white light
(6500K, cold), mainly when integrated to daylight, improving performance and
comfort, attention and relaxing. | |
