South Australia it depends on the Award (like a default contract for a particular kind of work, it sets minimum conditions)

But at a bare minimum, if you're working at a shift of 4 hours or more, you're required to be given a 15 minute paid tea break.

If you're working 5 hours or more, Add a 30 minute unpaid lunch/dinner break.(*minimum, 1 hour max if scheduled - max as otherwise it's really just split shifts)