ILLUMINANCE 101
What is 'illuminance'?
Illuminance, or light level, is the total amount of visible light that falls on a surface.
What are 'lumens'?
Lumens are a measure of the total amount of visible light emitted by a source.
What is a 'lux'?
In the metric system, illuminance is measured in lux, where 1 lux = 1 lumen per m²
How to calculate illumination:
lumens per lamp * utilization coefficient * light loss factor
area per lamp (m²)
Recommended illumination in different work spaces
Activity
Illumination (in lux)
Public areas with dark surroundings
Simple orientation for short visits
Working areas where visual tasks are only occasionally performed
Warehouses, Homes, Theaters, Archives
Easy Office Work, Classes
Normal Office Work, Study Library, Groceries, Show Rooms, Laboratories
Supermarkets, Mechanical Workshops, Office Landscapes
Normal Drawing Work, Detailed Mechanical Workshops, Operation Theatres
Detailed Drawing Work, Very Detailed Mechanical Works
Performance of visual tasks of low contrast and very small size for prolonged periods of time
Performance of very prolonged and exacting visual tasks
Performance of very special visual tasks of extremely low contrast and small size
20 - 50
50 - 100
100 - 150
150
250
500
750
1000
1500 - 2000
2000 - 5000
5000 - 10000
10000 - 20000