Ratio of illuminance and uniformity requirements
Ratios between different illuminances and uniformity requirements.
| Illuminance, working area |
Illuminance, immediate surrounding area |
Illuminance, peripheral surrounding area in relation to immediate surrounding area |
| ≥ 750 | 500 | 1/3 |
| 500 | 300 | 1/3 |
| 300 | 200 | 1/3 |
| 200 | 150 | 1/3 |
| 150 | Working area | 1/3 |
| 100 | Working area | 1/3 |
| ≤ 50 | Working area | 1/3 |
Uniformity within the working area depending on the vision task and activity. Uniformity within the immediate surrounding area min/avg at least 0.4. Uniformity within the peripheral surrounding area min/avg at least 0.1.