SAN FRANCISCO (KRON) — Tens of thousands of Kaiser Permanente employees have authorized a strike to begin if an agreement with the hospital chain fails.

There are 58,000 Kaiser workers in California and 19,000 of them are in the Bay Area.

Union leaders say it could be considered the biggest strike by healthcare workers in U.S. history. Three other states, Washington, Colorado and Oregon, have also authorized a strike.

Those three states joining could potentially bring in around 15,000 more workers going on strike. The union says no strike will occur before October until the contracts of more than 85,000 workers have expired.

Kaiser Permanente and the union have not been able to come to an agreement over wages, staffing issues and how the negotiations have been going so far. The union says Kaiser is not willing to listen to concerns.

Kaiser released the following statement that read in part:

“Kaiser Permanente is fully committed to reaching an agreement with the unions affiliated with the Coalition just as we have done in every national bargaining since 1999. Our priority is to reach an agreement that is mutually beneficial and ensures we can continue to offer our people market-competitive pay and outstanding benefits.”

The workers are asking for a 7 percent wage increase in the first two years, and a 6.25 percent increase the following two years.

Both sides will meet again twice next week.

“Our priority is to reach an agreement that ensures we can continue to provide market-competitive pay and outstanding benefits. We are confident we’ll reach an agreement before the national agreement expires on September 30 that strengthens our position as a best place to work and ensures that the high-quality care our members expect from us remains affordable and easy to access,” Kaiser said in a statement to KRON4.