NEW YORK (CBSNewYork/AP) — The union representing 18,000 nurses at 14 private hospitals in New York City says its members could go on strike if negotiations with management fail.

New York State Nurses Association members said Wednesday they are fighting for higher staffing levels to protect patients.

“We believe that our patients’ lives depend on this, and we just can’t allow this to continue anymore,” union President Judy Sheridan-Gonzalez told 1010 WINS.

She said nurses are overworked because hospital are understaffed.

“We’ve gotten extraordinary amounts of support from the community,” Sheridan-Gonzalez said. “They trust us. They know that what we’re talking about is true. Any patient who has been in the hospital knows that there’s just not enough nurses to take care of them. Nurses are running around, often working 12-hour shifts without even being able to go to the bathroom.”

Sheridan-Gonzalez said hospitals have refused to work with them on the issue.

“Nurses have been threatened with arrest for just discussing staffing with co-workers. Some nurses have been escorted out by armed security guards for talking about staffing,” Sheridan-Gonzalez said. “This desire to intimidate us out of advocating for our patients is unconscionable, and we’re not accepting that. We’re not going to be silenced.”

Four days of negotiations are starting Wednesday.

The New York City Hospital Alliance denies that the hospitals are understaffed.

“NYSNA cannot point to a single shred of evidence that supports their claim that current staffing levels are unsafe or inadequate, which is not surprising given that these hospitals are all nationally recognized for the excellence of care they provide,” said Farrell Sklerov, a spokesperson for the Hospital Alliance.

Sklerov said the Hospital Alliance is “extremely disappointed” that the union is taking steps toward a “completely unnecessary strike.”

“We have remained committed to bargaining in good faith and have put forward a significant proposal that demonstrates the value we place on our nurses, who are the best in the business and should be rewarded for their essential role in the delivery of excellent care,” Sklerov said.

Each of the hospitals has put together contingency plans in the event of a work stoppage.

“We hope NYSNA rethinks their bargaining strategy at this critical moment, rather than putting the city on a path towards an unnecessary and completely avoidable health care crisis,” Sklerov said.

The nurses have been without a contract since around the beginning of the year.

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