Better reproducibility is obtained by dead weight loading. Here the hardness is expressed in IRHD International Rubber Hardness Degrees. Both IRHD, Durometer tests requires rubber specimen of definite dimensions. As per the ASTM (D 2240- Defines apparatus to be used and its sections such as diameter , length of the indentor , force of spring and D 1415 Defines specimen size), DIN, BRITISH & ISO Standards following test conditions have been laid for measuring SHORE A HARDNESS of rubber products.

1)    The specimen should be at least 6 mm in thickness.

2)    The surface on which the measurement made should be flat.

3)    The lateral dimension of the specimen should be sufficient to permit measurements at least 12 mm from the edges.