Hi

A question on transporting SUP. A 10 foot SUP is just too long to fit fully in vehicle (don't want to use racks) but will fit with board slightly sticking out of tailgate window.
My CRV has a tailgate window that opens. Is it legal / illegal to drive with this window open ?
I understand that consideration needs to be given to CO emissions but if you open all windows and put AC on refresh mode it is not an issue for short distances.
But is it legal in Australia ?