Usually, general lighting is provided for classrooms. Luminaire characteristics and arrangement are determined by the type of class and its specific seating arrangement as well as room use. Free seating arrangements for team work and classic, aligned seating arrangements looking onto the chalkboard can be interchanged within short periods of time. Frequently, classic school blackboards are supplemented or even replaced by whiteboards, projector presentation surfaces and further information displays or charts. This also changes the students’ and teachers’ viewing direction over the course of the class periods. The lighting must be specified independent thereof.
Light influences people’s mood, emotions and mental attention. Light can also support circadian rhythms (circadian system) and impact the physical and psychological state of a person (for details see chapter “Light and non-visual effects”). Particularly in schools, the correlation of light and performance as well as the melanopic efficiency of dynamic light are important for learning.
Students prefer spending time outside in the daylight. Dynamic general lighting controlled according to the natural daylight progression adjusts the room lighting in the classroom to natural light levels in case of insufficient daylight supply. In EN 12464-1, a new lighting quality criterion was introduced to this effect: lighting variability.
In a long-term study attended by a German university, students and teachers exposed to “activating” lighting (650 lx, 12.000 K), “focused work” lighting (1.000 lx, 6.000 K) and “calming” lighting (300 lx, 2.900 K) were compared to a group of people exposed to standard conditions (300 lx und 4.000 K). The result of the benefit of dynamic lighting in schools shows:
reading speed increased,
error frequency in testing was reduced, and
restlessness in students decreased.
Chronobiologists recommend dynamic lighting in schools. In the morning, the starting colour temperature should be ca. 3.000 K, with a gradual increase up to 6.000 K until about 11 a.m. In evening schools and e.g. seminar rooms at universities, blue components should be switched off from around 6 p.m. and only long-wave light with roughly 2.700 K should light the room.
Dynamic light is realised using LED luminaires or luminaires with fluorescent lamps of different light colours, whose portion of the overall luminous flux is changed by dimming (see chapter “Light and non-visual effects”).