CHICAGO (WLS) -- Twelve nurses at the University of Illinois Hospital in Chicago have tested positive for COVID-19.A member of the Illinois Nurses Association told ABC7 on Friday that the dozen nurses weren't wearing personal protective equipment while working with patients who had not yet been tested for coronavirus."How would you know which ones are positive, which ones are not? So that's why we are not sure so why don't we just use masks every time we are in the hospital? And finally they listened this afternoon," said Terrence Yee.Yee said the hospital now allows nurses to wear their own personal protective equipment."These nurses served patients on the front line of the fight to contain the coronavirus pandemic and risked their lives to make sure patients received proper care," said Alice Johnson, the association's executive director. "We hoped their hospital and their government would protect them, but they failed."The University of Illinois Hospital released a statement Friday, saying that a limited number of the cases "are believed to be due to exposure in a health care setting.""All care providers at UI Health have been provided guidance to use personal protective equipment as recommended by the CDC and in some cases we have implemented recommendations that go beyond these guidelines," said Michael Zenn, CEO of the University of Illinois Hospital and Clinics. "Most importantly, our policy for COVID-19 is that all providers who care for patients confirmed to have COVID-19 or suspected of having COVID-19 should wear PPE. There are no circumstances in which we would ask our care providers to forgo PPE when caring for COVID-19 patients."Read Zenn's full statement below: