How old must a toddler be for a jacuzzi?

I think a child any age will be fine in a jacuzzi as long as you don't "shock" them when putting them into the water. Maybe start with there feet then slowly put the rest of their body in. Make sure you watch them closely as they probably won't be able to stay in very long, when there face starts to get red I would give them a break for awhile to let them cool down.