But hospital administrators say the walkout has not affected patient care.
Sutter Health is saying it is "business as usual." They have hired replacements, and they have assisted nursed so things appear to be normal here to be covered.
In the past, keep in mind nurses have gone on strike for only two days, not 10.
At 7:00 a.m. on Friday morning, registered nurses from ten Bay Area hospitals left their posts.
It's their third walk out in six months -- but this one is expected to last the longest, 10 days.
"I've taken on a second job in order to meet my obligations for the time we are on strike and if we have to go out again on a strike," said registered nurse Millicent Borland.
All hospitals affiliated with Sutter Health remain open. Replacement nurses have been brought in from around the nation. They have travel expenses, lodging and meals paid for by Sutter.
"We brought in our replacement nurses in. They are all on the ward. We have a lot of nurses who work here who have crossed the picket lines. The physicians are here, staff, so if any patient were to walk in the door, they wouldn't see any difference than on any other day," said Kevin McCormack from California Pacific Medical Center.
Registered nurses have been without a contract since last June. The major sticking point is over meal and rest breaks.
The union wants Sutter Health to add registered nurses whose only job would be to make sure meals and breaks happen.
"State law says I can take five patients now and later, but I can't take my patients and another nurses' or those patients won't be seen during that time," said registered nurse Jan Rodolfo.
But Sutter Health says they already follow the state-mandated nursing-to-patient ratio.
"Patient care is the one thing we are not willing to sacrifice," said McCormack.
Sutter Health says adding one break relief nurse for every five nurses would cost more than $88 million dollars over four years. It's the one issue dividing both sides.
"We literally have not given them a wage proposal in response because we want the discussion to be about staffing, lift teams and about meal breaks, not about wages," said Rodolfo.
Regarding wages, Alta Bates Summit in Oakland has offered nurses a 16.5 percent salary increase over four years, so there is an offer on the table. But again, keep in mind, each medical center is negotiating separately with the union.
The proposals may vary, and they may be different from medical center to medical center.