This paper investigates the impact that the static pressure (i.e., positive, neutral, or negative pressure with respect to ambient) within a commercial kitchen space may have on exhaust system performance, since in real kitchens this pressure may change for a variety of reasons. Within a laboratory environment, it was demonstrated that conditions of positive pressure did not impact hood capture while conditions of negative pressure adversely affected the ability of the exhaust hood to capture and contain cooking effluent. This paper explains that this adverse effect was due to a reduction in the exhaust airflow rate caused by an increase in static pressure of the exhaust system, not the static pressure condition itself. The paper presents the theory that supports this conclusion as well as implications for facility design and operation.

Units: Dual