What kind of pressure system does Category 3 refer to?

In the context of ventilation systems, particularly when discussing pressures within buildings and environments, Category 3 refers to a positive pressure system. A positive pressure system is one where the internal air pressure is greater than the external air pressure. This is often utilized to prevent external contaminants from entering the space, essentially creating a barrier to airborne pollutants or pathogens.

In healthcare environments, such as operating rooms or isolation rooms, positive pressure is crucial for maintaining a clean and sterile environment. The system ensures that any potential contaminants from outside do not infiltrate while also allowing the internal air to be filtered and controlled for quality.

Positive pressure systems are integral in various applications beyond healthcare, including laboratory environments and cleanrooms, where controlled airflow is vital for maintaining specific conditions favorable for sensitive processes or materials. Thus, understanding the importance of a positive pressure system is vital for anyone involved in design, maintenance, or operation of environments requiring controlled air quality.