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Lux Illuminance Chart | Light levels in Indoor,Outdoor

This page mentions lux or illuminance chart. It mentions recommended light levels in indoor and outdoor with lux or illuminance values including natural sources.

As we know light level is known as illuminance. It is basically amount of light measured on plane surface. It can be total luminous flux incident on a surface per unit area.

It can be measured in foot candles (ftcd, fc, fcd) or lux (in SI units). Following are the equations used to express relationship between various units of measurement used for illuminance.
➤1 Lux = 1 Lumen/meter2
➤1 foot candle (ftcd, fcd) = 1 lumen/sq. ft = 10.752 lux
➤1 lux = 1 lumen/sq. meter = 0.0001 phot = 0.0929 foot candle
➤1 phot = 1 lumen/sq. cm = 10000 lumens/sq. cm = 10000 lux

Chart of Light levels from natural sources (Lux or Illuminance)


Natural source Illumination (ftcd) Illumination (lux)
Sunlight 10000 107527
Full Daylight 1000 10752
Overcast Day 100 1075
Very Dark Day 10 107
Twilight 1 10.8
Deep Twilight 0.1 1.08
Full Moon 0.01 0.108
Quarter Moon 0.001 0.0108
Starlight 0.0001 0.0011
Overcast Night 0.00001 0.0001

Following chart mentions recommended light levels for different workspaces.

Chart of Light levels in Indoors


Light levels indoors Illumination (Lux, Lumen/sq.m )
Public areas with dark surroundings 20 to 50
Warehouses, Homes, Theaters 150
Easy Office Work, CLasses 250
Normal office work, PC work, Study library, Groceries, Labs, Show rooms 500
Super markets 750
Mechanical workshops, normal drawing work 1000
Detailed drawing work 1500 to 2000
Visual tasks with low contrast & very small size for prolonged periods of time 2000 to 5000
Training rooms 500
Auditoria 150 to 200
Child care centers, Parking , entrances, physical fitness space 500

Chart of Light levels in Outdoors

Following table depicts recommendations for light levels for roadways and sidewalks in lux (or fc) units.

outdoor light levels

Refer Lux vs Lumens >>, LED test equipments >> and Lux Light Meter >> used for testing lighting devices.



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