Permanent wiring of an extension lead to a FSU?

I carry out site inspections for a local authority and have recently across a number of 'multiway' extension leads screws to walls and wired directly via a FSU.

The flex cables being either surface run or in plastic box ducting.

Is this compliant with IET regs?

If it isn't, please could someone let me know which specific regulations apply?

Many thanks, Neil