CHICAGO (CBS) — Citing unfair labor practices, the Illinois Nurses Association announced it would go on a seven day strike at UI Health.

In a letter to Michael Zenn, the CEO of UI Health, the strike is set for next Saturday, September 12 beginning at 7:00 a.m.

According to the Illinois Nurses Association, the group announced a 995 to 12 vote “to authorize a strike against the Chicago hospital.”

“Negotiations began earlier this summer but after more than a dozen negotiating sessions, the hospital refuses to engage in a substantive discussion about achieving safe staffing by setting a limit on the number of patients that can be assigned to each nurse, a policy also known as “safe patient limits,” said Doris Carroll, RN, INA President and nurse at UIH. “Safe staffing is the most important issue in the new contact negotiations,” Carroll stressed.

The INA said the existing contract between the organization and University of Illinois Hospital expired on August 24.