Hamrhed,
Actually.... Yes ! I would think that there is little real danger to humans in the water while the ozonator is running since it is such a small amount and dissapates rapidly.
In fact, If you get into the tub without turning on the big pumps, the circ pump AND the ozonator would still both be running, so I guess it's OK. So why it shuts off when the big pumps are on is a good question.
Tim
Have you ever heard of the people that like to put their mouths over the air injectors and try and breathe underwater?