Got this off the owner's manual for NACRA

[color:"blue"] Design category C has been approved for this craft. Designed for voyages in coastal waters, large
bays, estuaries, lakes and rivers where conditions up to, and including, wind force 5 and significant
wave heights up to, and including, 6 meters may be expected. [/color] .

So, this being stated by the manufacturer, does it mean you void the warranty by racing outside of these parameters?

And, if this is the design parameter, should the PRO knowingly start races beyond these design limits (say, Force 6 wind)?

Who makes up these "categories"?