Assistant Laboratory Animal Technician (ALAT) Practice Exam

What happens when you open a door to a negative pressure room?

1. Air rushes into the room from the hall

2. Air rushes out of the room into the hall

3. The pressure remains the same

4. Air is neutralized

The correct answer is: Air rushes into the room from the hall

When you open a door to a negative pressure room, air flows into the room from the hall. This phenomenon occurs because a negative pressure room is designed to have a lower pressure inside compared to the surrounding areas. The purpose of this setup is to contain pathogens or contaminants within the room, preventing them from escaping into other areas. When the door is opened, the higher ambient pressure in the hallway effectively pushes air into the lower pressure environment of the negative pressure room. By doing so, the air movement helps to maintain the integrity of the negative pressure system, ensuring that any potentially harmful particles remain contained. The other options suggest scenarios that do not accurately depict the physical principles of pressure differentials, such as air rushing out of the room or remaining neutral, which contradicts the fundamental workings of airflow relative to pressure differences.