We carry out measurements of hardness °ShA and °ShD according to DIN 53505 by impact with head measurement and a reading accuracy of 0.5 units of hardness.

Standard measurement of elastomer hardness are:
IRHD (International Rubber Hardness Degrees), BS (British Standard) degrees and Shore A Durometer.
The first two are identical, however, Shore A Hardness may be measured as an instantaneous reading or as a 30 second reading. In the former case the value obtained is about 5 degrees higher than IRHD.

The hardness of any elastomer can be modified by compounding. Hardness is thus a control factor in the formulation of an elastomer for specific applications. Hardness values used for seal materials may range from as soft as 40 to 50 °ShA up to a very hard compound of 95 °ShA hardness.

Hardness (and therefore friction) is also affected by swelling. Swelling tends to reduce hardness and at the same time will increase the squeeze.

Similarly, hardness is affected by temperature, decreasing with increasing temperature, and vice versa.