Thank you for your email. As you may know that our ‘Flexitallic Novus 30’ is a premium soft gasket which generally made from aramid fibre using nitrile rubber as a binder. It is a general purpose material which suitable for use in a wide range of applications and has a good track record with many approvals including WRAS, BS 7531 etc. (please see additional information attached). Unfortunately that aramid fibre is not material recommended for use in extremely high temperature application. Thus, there is no fire safe test certificate available. Nevertheless, Flexitallic Novus 10 or Flexitallic Thermiculite range are the top recommended for high temperature application. Especially Thermiculite 815, it can withstand the temperature up to 1050°C without oxidation. Both are certified to fire safe test (API 607) (please see datasheet and fire safe test certificate).
Moreover, in terms of soft gasket which is not petroleum rubber (elastomer) we generally use terms ‘compression’ and ‘recovery’ rather than ‘shore hardness’ which is a term using for elastomers e.g. NR, NBR, EPDM, Nitrile or Viton. As you can see from Flexitallic Novus 30 datasheet, there are ‘compression’ and ‘recovery’ performance based on ASTM F36 available which should satisfy user for certain application.
Last but not least, if you need any additional information, please kindly let us know. We are looking forward to our collaboration and grow the business together.