Positive Air Pressure. This is in contrast to a negative pressure room, where air is sucked in. In the event that there was a leak, or a door opened, clean air.
The cleanrooms are used often in Hi-tech, medical, and food processing industries. Positive pressure means that the air pressure inside the case is higher than ambient. Positive pressure gets you less dust inside your case, but it is a bit against the laws of physics; hot air has bigger volume, so getting lots of intake fans and less exhaust fans means that the hot air is not.
Positive air pressure in a home in summer will force cool air out and have those same impacts on your comfort or your cooling cost.
Positive airway pressure treatment for obstructive sleep apnea.
Thingiverse is a universe of things. Positive End-Expiratory Pressure (PEEP) is the maintenance of positive pressure within the lungs due to insufficient expiratory time (Te), typically in the presence of severe air-flow obstruction (e.g. Positive pressure is used in cleanrooms where the priority is keeping any possible germs or contaminants out of the cleanroom.