What kind of pressure is typically required in a containment situation?

In a containment situation, the typical requirement is for negative air pressure. This setup is essential to ensure that the air flows into the containment area and not out of it. Negative pressure environments are designed to contain potentially hazardous materials, such as pathogens or allergens, preventing them from escaping into the surrounding environment. This is particularly crucial in laboratories working with infectious agents or in animal facilities where contamination must be controlled.

In some contexts, a positive air pressure might be appropriate, such as in certain hospital rooms to protect immunocompromised patients from external pathogens, but it is not the standard for containment situations designed to keep hazards contained and protect the external environment.