New Jersey currently has at least 11 “presumptive positive” cases of coronavirus COVID-19, prompting Gov. Phil Murphy to declare a state of emergency.

To prevent the outbreak from spreading further, hospitals around the state must take extra precautions if they have a patient come in who exhibits symptoms of the virus. At St. Peter’s Hospital in New Brunswick, a patient fills out a questionnaire. Then, if they show signs of having the virus, the hospital acts.

"If they're positive, they're giving a mask right at the door,” says Henry Redel, chief of infectious diseases. “We like to protect all of our healthcare personnel."

The person is then taken to the native pressure room for testing. St. Peter’s has 55 such rooms, which are used for a variety of communicable diseases.

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“The patient gets placed in the room, the door gets shut, it then becomes negative pressure so that contaminated air isn’t going anywhere else. It says with a patient in that room and gets exhausted outside, so that prevents the spread of the virus to other people,” says Kimberly Simon, director of infection prevention.

Simon says that the air that is exhausted outside goes through a filter and gets cleaned and discharged outside of the hospital through the roof. A series of sensors make sure that the room is working properly.

St. Peter’s officials say that multiple people with suspected cases of coronavirus have been treated at the hospital this year. All tests have come back negative.