Roughly 1,000 nurses walked off the job at Robert Wood Johnson University Hospital Thursday after failing to reach a contract agreement.The hospital has brought in replacement nurses to fill the work shifts. However, both sides have decided to put the welfare of patients first by allowing specialized nurses to cross the picket line if there is an emergency.The nurses union had been in negotiations with the hospital but could not settle on the most contentious part of a new contract, health care coverage. The nurses are entitled to free health care, but only at Robert Wood Johnson hospital. The union says the problem with that plan is most nurses don?t live anywhere near the hospital. The hospital responded by adding three more Robert Wood branches around the state but nurses are insisting that they?d prefer Blue Cross/Blue Shield coverage.