"You have a lot of important people that do a lot of important things that are out here over negotiations over a new contract," said Labor and Delivery Technician Karen Harden.
Other workers outside include cleaning staff, dietary and transport service workers.
At least one patient tells Action News care inside the hospital is suffering.
"Labs are delayed, tests are delayed, medications are delayed because there is not enough staff to cover anything," said Ernestine Fitzgerald.
A letter written on hospital letterhead indicated the workers would be locked out if they rejected Crozer-Chester's latest contract offer. Earlier this week, the 500 members of Laborers International Union Local voted down a 3 year contract offering 6% raises and a 3% bonus plus, what the union says, are higher health care premiums.
"They're offering 6% to the lowest paid workers that are impacted by today's economic situation," said LUI local business manager Tony Seiwell. "And they're giving more to those who make the most."
Those locked out are primarily techs, transport & dietary workers as well as environmental services employees who clean patient and operating rooms. Their salaries range from 12 to 20 dollars an hour.
The hospital declined an on-camera interview, but released a statement saying in part "a fair wage and benefit package was presented for many job classifications. Wages are 20% over area hospitals." It also says "Well trained individuals are available to replace the employees who choose not to return to work."
"We are willing to go back to the table as of now and get our people contracts. They don't want to. So here we are, standing strong," said Pat Murray of the LIU negotiating team.
The hospital says medical professionals are covering jobs left open by locked out workers.
Union workers say they wanted to keep working under the old contract until a new agreement could be reached.
The hospital says it has made it's best offer.
No word on if the two sides will meet again.
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