ACC stands for Acoat Colour Codification System. The ACC System uses a scientific framework enabling every conceivable shade of colour to be precisely labelled and coded according to a logical clasification system.  It classifies colours according to their three primary characteristics: 

• Colour tone
• Saturation
• Clarity

Coding - Based on its place in the system, each colour is assigned a code that firstly reflects the colour tone, then the saturation and finally the degree of clarity. L8.10.60, for example, is a colour in the green sector (L8) with low saturation (10) and a high degree of clarity (60)

Colour tone - The colour tone indicates the nature of the colour, e.g. red, orange, yellow, green, blue, indigo and violet.  But given that colours shift gradually from one to another, colour tone is best reflected by an unbroken colour wheel associated with the colour spectrum.

The circle is divided into 24 sectors. A letter of the alphabet is assigned to each sector and each sector is then subdivided into 10 smaller sectors, numbered 0 to 9, allowing for a high degree of sophistication and providing a choice of 240 shades.

Saturation - A colour's saturation reflects its intensity or 'warmth'.  The higher the colour grade, the greater its saturation.  The less the colour is caturated the 'duller' it appears.  the degree of saturation is defined by the distance from the axis to the edge of the cylinder and is expressed as numbers on a scale from 00 to 99.

Lightness - All colours vary from light to dark.  The degree of clarity is defined by the distance from 00 to 99 along the central axis.  Black, which has the least level of clarity, is assigned the code 00, and the code for white - with maximum clarity - is 99.