According to BRE’s The essential guide to retail lighting:
The term 'luminous flux' describes the ‘Amount of light produced by a lamp; usually measured in lumens’
Lumen are related to lux (lx), the SI unit of illuminance, or amount of light on a surface, in that one lux is equal to one lumen per square metre (lm/m^2)
 Related articles on Designing Buildings Wiki
- Ballast or control gear.
- Colour appearance.
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- Daylight factor.
- Daylight lighting systems.
- Dichroic reflector.
- Discharge lamp.
- Extra-low voltage lamps.
- General lighting v task lighting.
- Lamp efficacy.
- Light pollution.
- Lighting energy numeric indicator LENI.
- Lighting of construction sites.
- Luminaire efficacy.
- Rights to light.
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