If you are not familiar with mathematical formulae, they can appear very confusing!  This page is intended to help you with the various formulae used in the IRC Rule:

*  Multiply

<  less than

>  greater than

^2   squared  (eg. 4^2 = 4 squared = 4 x 4)

^3  cubed (eg. 9.5^3 - 9.5 cubed = 9.5 x 9.5 x 9.5)

^0.5  square root  (eg. 25^0.5 = square root of 25 = 5)

m^2   square metres

( )  calculations shown iithin brackets are solved first  eg. 4*(3+3) = 4*6 = 24

If you would like clarification of any the formulae in the IRC Rule, please contact RORC or UNCL who will be able to help you.



If your boat is not a standard production boat with which we are familiar, or your boat has had modifications to the design, we usually ask for photos so that we can assess the boat in the fairest way possible.  In order to help us do this, we have put together some guidelines to show the type of pictures that are useful to us:

IRC photograph guidelines

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Header images by:

John Crawley (CAN IRC)  
Jinno (c/o JPN IRC)
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