Research on the pressure differential characteristics in the biological safety isolation chamber for infectious patient transport

To meet the demands of biological safety isolation during long-distance flights, we constructed a container-type isolation chamber through a ventilation control system. Instrumented with real-time differential pressure transducers, we recorded cabin atmospheric pressure variations and containment integrity metrics across three flight phases: takeoff, cruise, and descent. Experimental findings demonstrated that interzonal pressure differentials maintained ≥15 Pa across adjacent functional compartments throughout all flight phases. Significantly, the ward-to-cabin differential pressure sustained absolute values exceeding 40 Pa, creating a stepped pressure gradient that enforced unidirectional airflow from clean zones to containment areas. The cabin pressure fluctuated mainly during takeoff and landing, while the changes during the cruise stage were relatively unremarkable. The pressure difference absolute value changes in each functional area of the isolation chamber are basically consistent with the pressure change pattern of the aircraft cabin, primarily influenced by internal air temperature and pressure shifts. It is recommended to use a pressure difference redundancy control method to facilitate simple and reliable pressure difference and pressure gradient control, which method helps to maintain the stability of the biological safety isolation chamber during the flight process and prevent potential cross-contamination. Practical Application This research provides building industry professionals with critical insights into maintaining pressure differential systems for biosafety isolation chambers during air transport. By validating the efficacy of ductless, power-distributed ventilation and redundant pressure control, the study offers practical solutions for ensuring stable airflow gradients in mobile medical units. These findings are directly applicable to the construction of modular healthcare facilities, emergency response units, and high-containment environments, where reliable pressure management is essential for infection control. The proposed methods ensured directional airflow and biosafety across multi-zone isolation syste.