Hardness table (conversion)

References:

Shore A / D - Determination of penetration hardness by means of a hardness tester (Shore hardness)
ISO 868 : 2003 specifies a method for determining the penetration hardness of plastics and ebonite by means of durometers of two types: type A is used for softer materials and type D for harder materials. The method allows measurement of either the initial indentation or the indentation after a specified period of time, or both.

IRHD (International rubber hardness graduation)
It is a method to characterize an elastomer by its resistance to penetration of an indenter of known geometry by a known force. The microtechnic is reproduced in irregular, flat, surfaces, and in cross sections as small as 1mm thick ( 0,4" ). The readings are similar, but not identical, to Shore model ( TM , Wilson - Shore Instruments)

ASTM D 1415
http://www.astm.org/Standards/D1415.htm

ASTM D 2240
http://www.astm.org/Standards/D2240.htm

DIN 53505
http://www.beuth.de/en/standard/din-53505/24622623

ISO 7619
http://www.iso.org/iso/catalogue_detail.htm?csnumber=50756

Understanding the "IRHD" and "Shore" methods used for rubber hardness measurement
http://www.wallaceinstruments.co.uk/sites/wallaceinstruments.co.uk/files/styles/thumbnail/public/paper2.pdf