Forest Service is roughly the same : All inclusive unit generally for Suppression Repair; suppression safety training / PPE required.
It’s my understanding that for safety reasons only members of the module are allowed to load the chipper, but in practice only once did I see a safety team uphold that. Generally a hand crew is teamed up with the chipper to help.
I’ve also seen a chipper/mini excavator combined module that operated independently chipping larger diameter material.
Demand varies with fire.
As for project work, if chipping is required in a timber sale/service contract, the contractor takes care of all equipment needs. Work by FS personnel is generally pile and burn or lop and scatter, I haven’t seen chipping done.