I just copied this info below on 8436 Cable:
The cores are intended for use as LINE, NEUTRAL & EARTH - so its essentially similar to Twin & Earth & other 2core + CPC cables. (the cpc is in constant contact with the aluminium foil shield) The XLPE / LSF Low Smoke Flume shielded construction means Flexishield offers fire extinguishing & EMC properties, & is fully recognised by BS7671:2011
Harmonised core colours (Brown/Blue) & white outer-sheath.
This cable is one of the very few to meet the demanding requirements of BS 8436 - & it actually exceeds the requirements of a huge number of lesser cables, e.g. BS6004 PVC cables such as 6242y Twin & Earth. Unlike those, its sheath isn't harmed by UV rays, polystyrenes, creosote, oils etc. - meaning it can replace standard cables, both indoors & out.
Due to its particular qualities, & its combination of LSF XLPE insulation & covering, the cable is extensively used in modern buildings. In fact, its often used to wire listed, prestige & vulnerable buildings in their entirety - completely replacing conventional PVC covered cabling.
If you're not familiar with the likes of Flexishield, this cable has quite specific properties... It's encased in a aluminium foil tape sheath, which makes the cable beautifully easy to work with - its uncannily light for its size, its highly dressable, & termination is so quick & easy it spoils you for all other cables! No requirement to ferrule or gland off - just ring with a Jokari etc. or even a knife, & the outer sheath breaks off. Even a DIYer will be terminating like a pro!
The aluminium sheath of Flexishield has been designed to meet the stringent requirements of BS8436 - most notably, that Standard's testing against piercing of the cable's outer sheath by the likes of nails & screws, causing the guaranteed operation of the protective device.
Therefore, cables passing the regimes of BS8436 (& there are very few) are qualified for use, unprotected & buried in walls at less than 50mm from the walls surface - even outside the 'safe zones' & without 30mA Residual Current Device protection!
Other than BS8436, the ONLY other cables permitted for such installation are MICC (Pyro) or SWA (SteelWiredArmour) which are hugely more time consuming to install & terminate - & both require specific glands to be fitted at every point.
All of which makes BS8436 cable uniquely useful. Whether its to completely wire an entire building, or simply to 'get-you-out-of-jail' on those unexpectedly awkward circuits where compliance with BS7671 couldn`t otherwise be achieved, Flexishield is often the only choice. Its not always desirable, or possible to protect every circuit, or extension of a circuit, with a 30mA RCD. In many cases, use of BS8436 Flexishield removes the requirement. Every smart spark should carry some on his van!
