As visual perception varies logarithmically, it is helpful to have an appreciation of both illuminance and luminance by orders of magnitude. To help compare different orders of magnitude, the following list describes various source in lux, which is a lumen per square metre.

Lux and illuminance are crucial in determining the appropriate lighting levels for different spaces. While illuminance refers to the amount of light falling on a surface (measured in lux), different applications require specific lux levels for optimal visibility and comfort.

Common outdoor light levels at day and night: The outdoor light level is approximately 10000 lux on a clear day. In a building in the area closest to the windows the light level may be reduced to approximately 1000 lux. In the middle area it may be as low as 25 - 50 lux. Additional lighting is often necessary to compensate low levels.

The Illuminating Engineering Society (IES) recommends the following footcandle levels to ensure adequate illumination and safety for occupants. Below is a guideline for common areas to assist in achieving appropriate light levels with the greatest energy-e ciency.

These foot-candle lighting levels are recommended from the Illuminating Engineer Society’s (IES) by application. Contact a representative now for exact levels. 1-800-303-5332

Today the light level is more common in the range 500 - 1000 lux - depending on activity. For precision and detailed works, the light level may even approach 1500 - 2000 lux. Generally, factors that affect the effectiveness of illumination are quantity and quality of light, amount of flicker, amount of glare, contrast and shadows.

number of recommended illumination levels for outdoor lighting. We summarize some of these recommendations below, and in some cases the original tables have been simplified.

A daylight factor (DF) is the ratio of the indoor daylight level to the outdoor daylight level [7]. The minimum DF for libraries is 2, and the average is 5 [8]. Although natural lighting is the...

Mar 7, 2021 · The table below provides recommended light levels from the IESNA Lighting Handbook and LPD levels from the IECC 2021 (using the Space-By-Space Method for calculations). Check your local jurisdiction for other or more stringent requirements.

Mar 6, 2025 · The Bortle Scale Chart (or Bortle Scale Map) is a tool used to measure the night sky’s brightness at a particular location. It was created by John Bortle, an amateur astronomer, to help other amateur astronomers evaluate the darkness of …