Unpaid "training"??

Just wondering if anyone knows about unpaid work at a job. DH has been hired for a job (truck driving) and needs to know a certain route. So he is to be accompanied by a co worker for this route and this will continue for 2 more days unpaid ( 10 hour shifts roughly)
Is this legal? Doesn't seem right to me to have several days unpaid :/

Has he signed a contract? Could that have been in it?
Maybe ring wage line, but way up if it's worth it over a job in the long run.
In my industry, you must complete volunteer hours in order to gain qualification.
Xxx

Might depend on the company and the contract. Where I work all training is paid

check this out: Unpaid work - Fact sheets - Fair Work Ombudsman

No contracts signed yet, and turns out it's about $50 a day or something like that. Still sounds dodgy $150 for 30 hours work. Peanutter I did look that up, but a little confused as to what type of unpaid work DH is doing exactly. I'll look into it some more thanks :)

All my training has been paid.