Airflow patterns through single hinged and sliding doors in hospital isolation rooms - Effect of ventilation, flow

Petri Kalliomäki1,2, Pekka Saarinen1,2, Julian W Tang3,4

  • 1Finnish Institute of Occupational Health, Lemminkäisenkatu 14 - 18 B, 20520 Turku, Finland.

Building and Environment
|April 15, 2020
PubMed

Insights

Sliding doors in isolation rooms are better than hinged doors at preventing pathogen spread. They minimize airflow during opening and simulated human passage, enhancing hospital infection control.

Area of Science:

  • Healthcare Engineering
  • Infection Control
  • Fluid Dynamics

Background:

  • Negative pressure isolation rooms are critical for containing airborne diseases in hospitals.
  • Door operations and personnel movement can compromise containment by transferring pathogens.

Purpose of the Study:

  • To compare airflow patterns and pathogen transport through hinged versus sliding doors in isolation rooms.
  • To evaluate the impact of ventilation rates and pressure differentials on containment.

Main Methods:

  • Simulated human passage and door operation (hinged and sliding) were used to study airflow.
  • Smoke visualization and tracer gas measurements quantified air exchange across the doorway.

Main Results:

  • Hinged doors generated greater airflow across the doorway than sliding doors.
  • Ventilation rates had minimal impact on airflow with hinged doors; results were variable with sliding doors.
  • A supply-exhaust flow rate differential significantly reduced air transfer for both door types.

Conclusions:

  • Sliding doors are preferable for isolation room design due to lower airflow exchange during operation.
  • Minimizing air transfer through doorways is crucial for effective infection control in healthcare settings.

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