Positive pressure is a pressure within a system that is greater than the environment that surrounds that system. Consequently if there is any leak from the positively pressured system it will egress into the surrounding environment.
Use is also made of positive pressure to ensure there is no ingress of the environment into a supposed closed system. A typical example of the use of positive pressure is the location of a habitat in an area where there may exist flammable gasses such as found on an oil platform.
This kind of positive pressure also used on Operation theaters and IVF labs. To maintain positive pressure the room should be well sealed without any loop holes
Hospitals may have positive pressure rooms for patients with compromised immune systems. Air will flow out of the room instead of in, so that any airborne microorganisms (e.g., bacteria) that may infect the patient are kept away.
Amphibians use this process to respire, whereby they use positive pressure to inflate their lungs.
This process is important in human and chick development. Positive pressure, created by the closure of anterior and posterior neuropores of the neural tube during neurulation, is a requirement of brain development.
Famous quotes containing the words positive and/or pressure:
“I am positive I have a soul; nor can all the books with which materialists have pester’d the world ever convince me of the contrary.”
—Laurence Sterne (1713–1768)
“The area [of toilet training] is one where a child really does possess the power to defy. Strong pressure leads to a powerful struggle. The issue then is not toilet training but who holds the reins—mother or child? And the child has most of the ammunition!”
—Dorothy Corkville Briggs (20th century)