Wiring regulations in the UK are described within BS7671.
BS7671:2008 was issued in 2008, and has had three amendments which were published in 2011, 2013 and most recently 2015.
The original version had a red cover. The amendment 1 reprint had a green cover, Amendment 2 was issued as a separete update, and Amendment 3 was printed with a yellow cover.
Amendment 3 is applicable up to 31 December 2018, after which the new 18th Edition applies.
BS7671 Wiring Regulations and On Site Guide (Yellow 2015 Edition)
A look at both BS7671 and the companion On Site Guide, 17th edition 3rd amendment as published in 2015.
TT supply with a metal consumer unit
Problems in complying with the 17th edition 3rd amendment wiring regulations with TT electricity supplies.