How we can select the correct type of MCB and RCD for our home? (By UK Standard) I want all details with clearly steps. Thank you my dears.

• Residual Current Devices (RCDs)

RCDs protect you against serious electric shock if there is an electrical fault in your home.They detect 'leaking' electricity from a circuit (e.g. a damaged cable) and respond by disconnecting the electricity supply from the circuit.Most modern homes have an RCD fitted in their distribution/ fuse board, but older homes may need to install one.RCDs are also available to fit at a socket outlet. These should be used for tools and outdoor equipment.You should check that your RCD is working correctly by pressing the test button marked 'T' or 'Test'.

Distribution Boards(For Mounting Miniature Circuit Breakers) Wide range of Sturdy, Spacious, Aesthetically designed Newtech Distribution Systems are suitable for all type of MCB's. The units are fabricated from the best quality CRCA Steel Sheets for good strength and finish. The distribution Boards are supplied duly fitted with Busbar, Din-Channel and Neutral link.Distribution Boards are painted with latest powder coating technology. This ensures superior quality finish and also provide protection against corrosive atmosphere.http://www.newtechmcb.net/mcb-distribution-boards.html

I want some calculations and relations..