Comparison between Hospital Single Air Unit and Central Air Unit for Ventilation Performances and Airborne Microbes

Paradee Chuaybamroong,Pipat Sribenjalux,Piyapong Choomseer

doi:10.4209/aaqr.2007.04.0027

Paradee Chuaybamroong, Pipat Sribenjalux + Show 1 more

Open Access

https://doi.org/10.4209/aaqr.2007.04.0027

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Abstract

Ventilation performance in two units equipped with a single, hanging air conditioner having no filter, and another two units equipped with a central air conditioner with HEPA filter were compared for the air change rate, air velocity profile, and microbe concentration in a 814-bed public hospital from February to May 2006. It was found that microbe concentrations in units using a single air conditioner were about two times higher than those in central air conditioner units. Within the same type of air conditioner, increasing ventilation rate resulted in decreased microbe concentrations.

Highlights

Air conditioning systems are well known for contributing to the microorganisms in an airconditioned room through different mechanisms, especially when sufficient maintenance is not performed (Maus and Umhauer, 1997)
This study was conducted in order to investigate the microbe concentrations along with ventilation performance in terms of the air change rate and air velocity profile in hospital units that are equipped with a single, hanging air conditioner with no filter, and units installed with a HEPA filter in a system
The room volume and the layout of new-born intensive care unit (NICU) is similar to pediatric intensive care unit (PICU), which are about 364.5 m3 each (9 m u 9 m u 4.5 m), whilst the room volume of intensive care unit (ICU) is approximately 240 m3 (6 m u 10 m u 4 m), and that of Burn Unit is 486 m3 (9 m u 12 m u 4.5 m)

Summary

INTRODUCTION

Air conditioning systems are well known for contributing to the microorganisms in an airconditioned room through different mechanisms, especially when sufficient maintenance is not performed (Maus and Umhauer, 1997). Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) (Kowalski and Bahnfleth, 1998), normally requires that hospital clean rooms have a series of filters for the air flowing in, such as 25%, 90% and 99.97% efficiency (HEPA) for an operating room, and a central air system. This study was conducted in order to investigate the microbe concentrations along with ventilation performance in terms of the air change rate and air velocity profile in hospital units that are equipped with a single, hanging air conditioner with no filter, and units installed with a HEPA filter in a system. The results of ventilation performance and microbial concentrations were compared

METHODS

RESULTS AND DISCUSSION

CONCLUSION