i do not have the legal answer, but if it were me, I would worry about the weight part, more than the age! As such, if my daughters were still that young, currently 16 and 19, or the twin sons, 22, and above 80 lbs, body parts large enough size wise such that when it inflated it held on them etc. I'd go for it!
She drives me boat,
I drives me dinghy!