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A nurse wears a surgical mask during a protest outside of the University of California San Francisco medical center August 5, 2009 in San Francisco, California. The California Nurses Association, which represents nurses working across the University of California system, had threatened a walk-out on Wednesday over contract negotiations.
The University of California has reached a tentative labor agreement with unionized nurses at its medical and student-health facilities.
The preliminary deal avoids a possible one-day walkout by the nurses that was scheduled for Wednesday.
The contract calls for annual 4 percent pay increases through 2017.
The Los Angeles Times reported Sunday that the four-year agreement still needs to be voted on by the 11,700 University of California nurses who belong to the California Nurses Association.
The newspaper says the nurses have agreed not to join a one-day strike Wednesday in sympathy with a walkout scheduled by other unionized patient-care workers, custodians and food workers at the university's five medical centers and 10 campuses.