Triathlon bike design rules?

Can anybody tell me where I can view a copy of the rules governing bike design for triathlon in the UK and USA? I am planning on building a fairly radical machine for Ironman distance events but I obviously want it to be race legal.

Cheers AndyA

Not sure about the UK rules, but here are the requirements for USAT races:

http://www.usatriathlon.org/Rules_Officials/rules.htm#5.11
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