workers on Friday threatened further if executives don't meet their demands over health-care staffing and job outsourcing.
More than 75,000 Kaiser are scheduled to end a three-day in California, Colorado, Washington and Oregon at 6 a.m. Saturday local time. The current strike, which began Wednesday, is said to be the largest walkout by health-care workers in U.S. history.
Nearly 60,000 of the workers currently on strike are in California where Kaiser is headquartered.
The Coalition of Kaiser Permanente Unions said workers will provide 10 days notice before walking out again.
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Bargaining sessions between workers and Kaiser executives are scheduled for next Thursday and Friday.
Disagreements over job outsourcing have become a major sticking point in recent negotiations, according to the coalition. It accuses Kaiser of refusing to limit outsourcing and subcontracting jobs.
Kaiser, the largest health-care nonprofit in the U.S., said Thursday that tentative agreements have been reached in several areas and that the company is committed to negotiating a new contract.
Workers are also demanding long-term investments to increase staffing amid a workforce shortage. The coalition of unions has said the short-staffing crisis has led to unsafe working conditions that are affecting the quality of care patients receive.