Lux Levels in Office Lighting: A Guide Based on EN 12464-1
Short answer
According to EN 12464-1, an average of 500 lux, a glare limit of UGR ≤ 19, uniformity of 0.60 and at least CRI 80 are targeted at office desks used for writing, reading and screen work. 500 lux is also enough in meeting rooms and 100 lux in corridors. Low-glare luminaires and a 4000K colour temperature are common choices in offices with screens.
In an office, light is directly responsible for productivity and comfort: insufficient light means eye strain and errors, while too much or uncontrolled light means glare and unnecessary energy consumption. In Europe and Türkiye, the lighting of indoor work areas is planned according to the EN 12464-1 standard.
Four basic values
- Average illuminance (Ēm, lux): the amount of light falling on the working plane.
- Uniformity (Uo): the ratio of the minimum illuminance to the average; no end of the desk should be dark.
- Glare limit (UGR): the degree of glare from the luminaires; lower is better.
- Colour rendering (Ra / CRI): how accurately colours are shown.
Target values for office areas
| Area | Illuminance (lx) | UGR | Uo | Ra |
|---|---|---|---|---|
| Writing, reading, screen work | 500 | ≤ 19 | 0.60 | 80 |
| Technical drawing | 750 | ≤ 16 | 0.70 | 80 |
| Meeting room | 500 | ≤ 19 | 0.60 | 80 |
| Reception desk | 300 | ≤ 22 | 0.60 | 80 |
| Archive | 200 | ≤ 25 | 0.40 | 80 |
| Corridor | 100 | ≤ 28 | 0.40 | 40 |
The values in the table are typical targets from EN 12464-1; in a project, the table in the current edition of the standard and the specific conditions of the space should be used.
Screen work and glare
In today's office, most work is done on screens. If bright spots from the luminaires are reflected on the screen, the eye has to keep adapting. That is why luminaires with UGR below 19 and opal or micro-prismatic diffusers are chosen for screen areas, and luminaires are placed so that they are not reflected in the screens rather than directly above the desks.
Colour temperature
4000K neutral white is the common choice in work areas: it supports alertness and shows colours naturally. 3000K is more relaxing in break and kitchen areas. Tunable white systems that change the colour temperature during the day are the basis of human-centric lighting.
Energy: the same light with less consumption
- High-efficacy luminaires: linear luminaires of 120 lm/W and above.
- Daylight sensors: luminaires near windows dim according to the daylight.
- Presence sensors: lights switch off in empty meeting rooms, archives and toilets.
- Central control with DALI: scenes, scheduling and fault monitoring.
Conclusion
The targets in office lighting are clear: 500 lux at the desk, UGR ≤ 19, good uniformity and CRI above 80. The layout that achieves these targets with the least energy is found by calculation. If you would like a calculation and layout plan for your office, you can explore our lighting design service.
Frequently Asked Questions
How many lux should an office have?
An average of 500 lux is targeted at desks. Typical values are 750 lux for fine work such as technical drawing, 200 lux in archives and 100 lux in corridors.
What does UGR 19 mean?
UGR (Unified Glare Rating) is the degree of glare from luminaires; the lower the value, the less glare. For screen work in offices the upper limit is 19.
Which colour temperature suits an office?
Usually 4000K neutral white; it supports concentration and shows colours naturally. 3000K can be preferred in break areas.
How can office lighting energy be reduced?
High-efficacy (lm/W) luminaires, daylight sensors near windows, presence sensors in meeting rooms and toilets, and dimming via DALI are the most effective methods.