Task Lighting Challenges
Tapping the full potential of task lighting requires innovation. Innovation involves cost, risk, and delay. Most organizations with modest resources have to wait for industry-wide improvements before they can apply task lighting in its most efficient form. On the other hand, an organization that is able to assign a talented individual to work on lighting efficiency may be able to achieve great improvements after a period of innovation and experimentation. When you set out to apply task lighting, be prepared for these differences between task lighting and conventional lighting:
• still emerging equipment. Until a few years ago, the right combination of fixtures and lamps for task lighting was not available. Conventional fluorescent and HID light fixtures are poorly adapted to illuminating individual task areas. Lack of ability to aim these types of fixtures is a critical weakness. Some incandescent lamps and fixtures are well adapted to aiming and localizing lighting distribution, but incandescent lighting is inefficient. However, the compact fluorescent unit is probably the breakthrough that will bring all the essential elements together. It has reasonably high efficiency, the appropriate range of wattage and light output, and fairly good color rendering. The small size of the unit makes it usable in fixtures that can be aimed. The fixtures themselves are not yet available as standard items, but they could be produced for a low price with only modest equipment and investment. The discussion below reports some successful task lighting that was set up on an experimental basis.
• incomplete understanding of lighting comfort. The initial failure of task lighting was caused partly by dissatisfaction with the quality of the light. In task lighting, the factors involved in visual comfort are less forgiving than in general lighting. However, all the essentials of visual comfort are covered in Reference Note 51, and it appears that task lighting can be created that will satisfy all the requirements.
•need for greater design effort. Contemporary lighting design achieves comfortable, attractive lighting with rote layout and conventional equipment. In contrast, task lighting requires a great deal of study, experimentation, innovation, and risk. These involve liability, and they add time to the design phase of the project.
•radically different appearance. Task lighting may dramatically change the appearance of the space. Task lighting does not have the regular checkerboard appearance of contemporary lighting. Light levels are not uniform throughout the space. If fixtures are ceiling-mounted, they may point in different directions and may extend different distances below the ceiling. Fixtures need large surface areas to avoid glare, but task lighting fixtures cannot be hidden in the ceiling, as in contemporary lighting. Therefore, task lighting fixtures are prominently visible as an element of the decor. Reflectors and glare shields, essential elements of task lighting, also project below the ceiling. The present stylistic prejudice toward making light sources invisible must be abandoned.