ISO 8442-5:2004 specifies the sharpness and edge retention of knives which are produced for professional and domestic use in the preparation of food of all kinds, specifically those knives intended for hand use.

Powered blade instruments of any kind are excluded.

Generally these types of knife are manufactured with blades of either plain edge design or with edges incorporating particular features to enhance or optimize aspects of cutting ability.

The following two types of knife blade are suitable for the cutting test.

• Type A edges: cutting edges which can be resharpened by the user and edges with a pitch greater than 1mm;
• Type B edges: cutting edges which are not intended to be resharpened on a steel.

Whilst these knives are predominantly manufactured with blades made from various grades of heat treated steels, the testing of knives of any construction or blade material is not precluded providing that the test criteria are met.

The principle of the testing is to reproduce a cutting action, by forward and reverse strokes, against a pack of synthetic test medium under controlled parameters.