ISO 7619-1:2010 specifies a method for determining the indentation hardness (Shore hardness) of vulcanized or thermoplastic rubber by means of durometers using the A scale for rubbers in the normal-hardness range; the D scale for rubbers in the high-hardness range; the AO scale for rubbers in the low-hardness range and for cellular rubbers; and the AM scale for thin rubber test pieces in the normal-hardness range.