Seems a bit odd - can you find a specific reference to this requirement in BS7671?

I have gone through BS7671 and can not find any reference to it

LSF or LSHF? See https://www.fscables.com/other/blog/lsf-vs-lshf-lszh-there-is-a-difference.html

Hi DevV. Due to its fire safety advantages, LSHF cable is preferable for use in areas with high fire risk. T&E PVC Might be unsuitable in a high street building with restricted exit routes. There is no specific regulation for a bathroom showroom. Reg 422.6 talks about locations of national, commercial, industrial or public significance needing cables with improved fire resisting characteristics. Have a read through chapter 42 to see if any of those regulations apply to your installation.

I've a feeling this sort of thing is covered by the The Construction Products Regulation and the requirements haven't (yet) been incorporated into BS 7671. (Although I think they may have found their way into some similar standards (e.g. B 6701 for telecoms wiring)).

It all seems a bit vague to me in terms of actual specific requirements for particular premises at present - but others here will know more and might be able to explain far better than I can.

A bit of bedtime reading: https://www.basec.org.uk/resources/electricians-guide-to-cpr/

   - Andy.

Is it on the designer to consider factors which may affect the safety of the occupants when specifying cables type in areas with high levels of public. I believe LSZH for example should be considered where high smoke levels would be likely to produce injury or panic, along escape routes 

In the UK, whilst BS 7671 recognises that `where applicable, cables need to meet CPR requirements and carry a Euroclass for fire performance`

the onus for selection of types of cables lays with the designer, consultant, specifier, installer for the installation. as per BS 7671 - Appendix 2 (informative) specifically item 17, the DLUHC `has not exercised these powers in respect of reaction to fire for cables`

Might be worth looking at

BS EN 50575 which became a legal requirement in July 2017

For protected escape routes cables need to be LSZH according to 422.2.1 so low flame propagation and low smoke emission.