<P> Negative room pressure is an isolation technique used in hospitals and medical centers to prevent cross-contaminations from room to room . It includes a ventilation system that generates negative pressure to allow air to flow into the isolation room but not escape from the room, as air will naturally flow from areas with higher pressure to areas with lower pressure, thereby preventing contaminated air from escaping the room . This technique is used to isolate patients with airborne contagious diseases such as tuberculosis, measles, or chickenpox . </P> <P> Negative pressure is generated and maintained by a ventilation system that removes more exhaust air from the room than air is allowed into the room . Air is allowed into the room through a gap under the door (typically about one half - inch high). Except for this gap, the room should be as airtight as possible, allowing no air in through cracks and gaps, such as those around windows, light fixtures and electrical outlets . Leakage from these sources can compromise or eliminate room negative pressure . </P>

When do you use a negative pressure room
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