Guide as PDF

General

General lighting refers to an even illumination, usually related to a horizontal working plane. Quantitative aspects are often a primary consideration at the work place or in pedestrian traffic zones. Direct lighting permits both diffuse and directed light. Indirect lighting, on the other hand, produces a very even, soft light.

direct, aimed

direct, diffuse

indirect

direct and indirect

direct, aimed

Observation

A direct and aimed general lighting produces an even illumination on the horizontal working plane. The architecture is visible and it is possible to orientate oneself and work in the room.

Conclusion

The directed light produces good modelling and brilliance. The uniformity on the working plane increases as the room height increases or as the beam angle widens. Directed light enables good appreciation of form and surface texture. The visual comfort increases as the cut-off angle increases. A feature of direct illumination is its highly efficient use of energy. At the work place, secondary glare must be taken into consideration.

Applications

Dubai International Airport

Centre Pompidou, Paris

Congress Palace, Valencia

ERCO, Lüdenscheid

direct, diffuse

Observation

A direct, diffuse general lighting designates an even illumination with respect to a horizontal working plane. The architecture is visible and it is possible to orientate oneself and work in the room.

Direct diffuse light produces a soft illumination with little shadow and reflection. The limited formation of shadow results in weak modelling capabilities. Shapes and surface textures are only slightly emphasised. One feature of using fluorescent lamps for general lighting is an efficient use of energy.

Applications

Direct, diffuse general lighting for
- working areas
- multifunctional rooms
- museums
- exhibitions
- pedestrian traffic areas

Preferred luminaire groups:
- light structures
- downlights
- wall-mounted downlights
- luminous ceilings

Congress Centre, Valencia

Prada, Milan

German Architectural Museum, Frankfurt

Fondation Beyeler, Basel

indirect

Observation

An indirect general lighting uses a ceiling, wall or other surface as a secondary reflector. The brightening of these surfaces that delineate the room or area gives an open spatial impression.

The diffuse light produces limited shadows and a weak modelling. Using indirect illumination alone gives a lower spatial differentiation. Compared to direct illumination, a considerably higher luminous flux is necessary for achieving the same illuminance on the working plane. The secondary reflector should boast a high reflectance. Direct and secondary glare are extensively avoided.

Applications

The prerequisite for an even distribution of light is a sufficiently high room. Indirect illumination should be mounted above eye-level. The distance from the ceiling depends on the level of evenness required and should be at least 0.8 m.

Indirect general lighting for:
- working areas
- multifunctional rooms
- pedestrian traffic areas

Preferred luminaire groups
- light structures
- uplights

British Museum, London

Ezeiza Airport, Buenos Aires

Eremitage, St. Petersburg

Villa, Salzburg

direct and indirect

Observation

Direct/indirect general lighting refers to a combination of direct and indirect illumination with respect to the horizontal working plane. The ceiling or walls serve here as reflection surfaces. The brightening of these surfaces that delineate the room or area gives an open spatial impression.

The uniformity on the working plane increases as the room height increases. Directed light enables a good appreciation of form and surface texture. The secondary reflector should boast a high reflectance. The uniformity on the ceiling increases the further away the luminaire is from the ceiling. A feature of general lighting with fluorescent lamps is its highly efficient use of energy.

Applications

Direct/indirect general lighting for
- working areas
- multifunctional rooms
- pedestrian traffic areas

Preferred luminaire groups:
- light structures
- pendant downlights