IRHD Hardness Testers – International Rubber Hardness Degrees

Test

Diameters mm

Test Range (IRHD)

N

N

N

Method N (Normal Test)

Foot: 20±1

Hole: 6±1

0.30±0.02

5.40±0.01

5.70±0.03

8.3±1.5

30-85

(high-hardness test)

Foot: 20±1

Hole: 6±1

0.30±0.02

5.40±0.01

5.70±0.03

8.3±1.5

85-100

Method L (low-hardness test)

Foot: 20±1

Hole: 6±1

0.30±0.02

5.40±0.01

5.70±0.03

8.3±1.5

10-35