To ensure that the installation complies with the designers intention and has been constructed and tested in accordance with the Requirements for electrical installations 1) "British Standard BS 7671 "Requirements for electrical installations" is the national standard in the United Kingdom for low voltage electrical installations." "The IET (formerly IEE) has published wiring regulations in the United Kingdom since 1882. Since their 15th edition (1981), these regulations have closely followed the corresponding international standard IEC 60364. Today, they are largely based on European CENELEC harmonization documents, and therefore are technically very similar to the current wiring regulations of other European countries. In 1992, the IEE Wiring Regulations became British Standard BS 7671 and they are now treated similar to other British Standards." "The BSI publish numerous titles concerning acceptable standards of design/safety/quality etc. in various fields. BS 7671 : 2001 (AMD No 2 : 2004) concerns the safety of electrical wiring in buildings (dwellings, commercial, industrial or otherwise) – generally known as the "Regs" (wiring regulations) – and succeeds the previous publication the 16th Edition of the Wiring Regulations. The On-Site Guide is a handbook that contains some information not in BS 7671:2001. It is meant as a handy notebook reference for electricians working on building sites." Source and further information: http://en.wikipedia.org/wiki/BS_7671 2) "Initial Verification Purpose: To ensure that the installation complies with the designers intention and has been constructed and tested in accordance with BS7671. Reason: ï‚· To ensure all materials and equipment utilised are of the correct type and comply to all relevant BSEN standards. ï‚· To ensure that all parts of the fixed installation are selected and erected correctly (in line with BS7671). ï‚· No part of the fixed installation is visibly damaged or otherwise defective. I&T must take place in order to confirm elements of the above. Certificates: Three forms are allowed for initial verification: 1. Multi signature Electrical Installation Certificate 2. Single signature electrical installation certificate 3. Minor electrical installation works certificate" Source and further information: http://www.djtelectraining.co.uk/downloads/ADL%20Initial%20Verification.pdf