Electrical cable nomenclature reading as per BS standards

Hi, Can anyone guide me on how to read cable types specified by cable manufacturers in UK. e.g. There is cable type 6491B in this each letter must have significance of reading which might be representing voltage grade of cable insulating material etc. simillaraly another cable type is 624xB LSZH cable.


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Hi,

I'm not so sure about the nomenclature of this cables. There are some naming conventions used, like the LSZH, it means low smoke zero halogen.

Thank you Sir, for the reply.
Hope to get more detailed answer. There has to be meaning of every digit in the nomenclature.