How many hours a week is it safe for a single caretaker to provide care?

I don't know if there are any formal guidelines written down anywhere unless your paid caregiver works for an agency. Even then I'm sure she sets her own schedule.

Try to trust that your caregiver won't take on any hours she can't handle and that if she opts to work a certain number of hours she knows best if she can handle the load.

The professional caregiver Agencies usually only allow 8 hours, but will allow more hours on a case-by-case basis with over-time being paid. A lot depends on the patient and the energy level of the caregiver.

I really think 7 days a week if too much. In a normal work week, those not doing caregiving have weekends off. But who would fill in on those days?

Are any of the family caregivers "seniors" themselves? That can be extremely physically and emotionally exhausting for an older person caring for a much older person. The "senior" will deny it, but I know for myself I just couldn't keep going at that pace.

Oh, if you have a paid caregiver who isn't family or who doesn't work for an Agency, make sure the patient has a "workman's comp" rider on his/her homeowners insurance, just in case the paid caregiver gets hurt on the job.