room pressure

In healthcare settings, room pressure is important for containing disease and providing patient safety. Providing positive and negative pressure rooms requires specialized construction and climate control equipment. For example, a minimum of 12 air-flow changes each hour must be maintained in order to sustain the desired environment; depending on the size and purpose of the room, more may be necessary.

Positive pressure rooms maintain a higher pressure inside the treated area than that of the surrounding environment. In positive pressure rooms, air can leave the room without circulating back in so that any airborne particle that originates in the room will be filtered out. and germs, particles, and other potential contaminants will not enter the room. Examples of positive pressure rooms in healthcare settings are:

• rooms housing patients with compromised immune systems

• rooms that must maintain a specific type of atmosphere, such as nurseries

• in vitro fertilization labs

• operating theaters

In contrast, a negative pressure room uses lower air pressure to allow outside air into the segregated environment. This traps and keeps potentially harmful particles within the negative pressure room by preventing internal air from leaving the space. Negative pressure rooms in medical facilities isolate patients with infectious conditions (AIIR) and protect people outside the room from exposure. Examples of negative pressure rooms are:

• waiting areas, especially in emergency rooms

• triage areas

• bathrooms

• AIIR (airborne infection isolation rooms) used for isolating patients with contagious, airborne diseases

• autopsy and dark rooms

• soiled laundry areas

• decontamination spaces