Define lamp characteristics
Relamping an industrial building

Lighting techniques designed to meet lighting needs are based on the following parameters:

• luminous intensity (in candela – cd) represents the energy flux radiated in one direction;

• luminous flux (in lumen – lm) is the quantity of energy that passes through a defined surface per unit of time;

• illuminance (in lux – lx) quantifies the flux received by a surface at a point;

• luminance (in candela per square metre – cd/m²) is the density of flux emitted per unit solid angle in one direction;

• colorimetry, whose values are color temperature (Tcp in Kelvin – K), varies from warm tints (3,300 K) to intermediate white (between 3,300 and 5,300 K for office lighting) to cool white (> 5,300 K);

• the color rendering index (CRI or Ra) defines the lamp's ability to reproduce colors faithfully;...