Membrane Ceilings in Healthcare Environments Study
Michael P. Pietrzak (Co-PI), David Vincent, Troy Ransdell, Tom Harvey, and Debajyoti Pati
David Duthu (Co-PI) and Tom Franklin, CCRD Partners, Houston, TX
Ting-Kwo George Lei, Fluid Dynamics Solutions, Inc., Clackamas, OR
Michael A. Edwards, LUWA
Patrick McLoad, Videographer, Director, and Producer
US Department of Health and Human Services Grant - 6 HFPEP070012-01-02
WHAT was the aim
The objective of the study was to assess the performance of membrane ceiling technology in controlling air particulate dispersion in exam rooms.
Why is it important
Hospital acquired infection control constitutes a major problem in healthcare delivery. Airborne infections have been documented as a major source of hospital acquired infection. A key factor contributing to airborne infection is air particulate dispersion as affected by the ventilation system design. Clean room technology (with membrane ceiling) has been successfully used in technology and pharmaceutical industries to control airborne contamination.
WHAT DID WE DO | HOW DID WE DO IT
This study examined the performance of membrane ceiling technology in controlling air particulate dispersion in a mock-up exam room. It included both performance tests in a mock-up room and a simulation study of six different ventilation system designs using Computational Fluid Dynamics (CFD) analysis. The study involved six key steps:
- Development of a room design for the study.
- Identification of an appropriate material for membrane ceiling.
- Video recording of smoke test in the mock-up room.
- Development of a base model in CFD and validation of the model using data from the mock-up tests.
- Simulation of six ventilation design configurations to examine air particulate dispersion patterns, and Mass Fraction (mf) Profile at 7.62 cm (3”) above patient.
- Comparative assessment of the six simulation models.
What did we find
Findings suggest that a membrane diffuser directed airflow ventilation strategy occupying approximately 20 to 30% of the ceiling surface and placed over the lower 2/3’s of the patient bed in a contemporary sized examination room provides a less turbulent airflow pattern and less mixing of the air between the patient and others in the room.
What is next
Although there appears to be advantages in terms of less turbulence, better air cleanliness and more predictable airflow, further studies will be needed to ultimately determine if membrane ceiling diffuser directed airflow ventilation - can actually translate into better outcomes in terms of cross contamination or infection transmission. The ultimate goal would be to lower cross contamination and infection rates without any significant increase in energy costs.