| Primary value | 300 - 500 lux |
| Applies to | Open-plan offices · Workstations · Meeting rooms |
| Exceptions | Drawing / design work → 750-1000 lux |
| Conference rooms → 500-750 lux | |
| Measured as | Average maintained illuminance on the desk surface (~0.75 m AFL). |
| Source | NBC 2016 — Part 8, Section 1, Table 1 ✓ Verified |
Office work — reading documents, screen work, writing — needs consistent, glare-free light at the 300-500 lux range. Below 300 lux, eye fatigue sets in quickly. Above 500 lux, energy is wasted unless task-specific.
Modern open-plan offices target 400 lux on desks via grid-mounted LED panels, often combined with daylight harvesting at perimeter zones.