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COLOUR RENDERING INDEX (CRI)
The quality of light
A measure of the ability of a light source to reproduce the colours of various objects. A light source with a CRI of 100 (Ra) would be
perfect and balanced in terms of colour reproduction, shading and contrast.
LUMEN DEPRECIATION (L70)
The deterioration in a lights performance after a time
Lumen depreciation values reflect the overall performance of a light source through its life. All light sources suffer from lumen
depreciation, which can be accelerated by poor thermal conditions, over voltage or incorrect application. L70 is the operating
time (hours) until the LED lumen output is depreciated to 70% of its initial lumens.

IP RATINGS
A fittings protection against dust and moisture
Ingress Protection (IP) is a value given to products that have particular protection against dust and/or moisture. The IP number is split,
the first digit represents the level of protection against dust particles while the second digit represents the protection against moisture.
For example IP00 has no protection against dust or moisture whilst a product with IP68 is dust tight and submersible up to 2m (see page
255 for more information).

Cone diagrams

Cone diagrams describe the amount of light at different distances from a fitting and are measured by the lux level.

DISTANCE (M) CONE WIDTH (M) ILLUMINANCE (LUX) DISTANCE (M) CONE WIDTH (M) ILLUMINANCE (LUX)
Ceiling Level

1 2.1 876 1 3.3 895

2 4.2 217 2 6.6 224
3 6.3 95 3 9.9 100

Distance from the The width the specified light intensity (lux) has spread at a measured The intensity of light measured by lux at
ceiling in metres distance (metres) from the fitting distances from the fitting

Understanding colour temperature

The colour temperature of a light source is measured in degrees Kelvin. Below is a Kelvin temperature chart with examples
of how colour temperature is used within different lighting applications.

STREET LIGHTING LIVING ROOMS KITCHENS & BATHROOMS OFFICE

1500K 2500K 3500K 4500K 5500K 6500K 7500K

Warm White Cool White

High Pressure Sodium Standard Incandescent Clear Metal Halide Cool White Fluorescent Natural White Metal Halide
2200K 2700K 4000K 4200K 5000K

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