Schools that installed systems with T-12 fluorescent lamps and magnetic ballasts during the 1950s and 60s have found the systems are not only inefficient but costly to operate. The trend is to replace these systems with more efficient T-8 lamps and electronic ballasts. According to Phil Onstott, owner of ProElectric in Tuscaloosa, who led the lighting project, the new system increased light levels and reduced energy and maintenance costs. The previous system generated a lot of heat on the ceiling, which increased air conditioning costs. Today, many students use computers within the classroom.
Screens can be difficult to see if lighting fixtures produce a high level of glare.
Providing some downlight with perforated holes or a lens in the bottom of the lighting fixture will make people think the atmosphere is brighter. They will feel more comfortable knowing the source of the light. Although fluorescent systems are probably the most popular for classrooms, other light sources may be appropriate for various areas. Incandescent lamps are the primary source of illumination in most homes. Fluorescent lamps produce light by activating selected phosphors on the inner surface of the bulb with ultraviolet energy generated by a mercury arc.