Final Report: Indoor Air Biocontaminant Control by Means of Combined
Electrically Enhanced Filtration and OAUGDP Plasma Sterilization
EPA Grant Number: 68D99025
Title: Indoor Air Biocontaminant Control by Means of Combined
Electrically Enhanced Filtration and OAUGDP Plasma Sterilization
Investigators: Kimberly Kelly-Wintenberg
Institution: Atmospheric Glow Technologies
EPA Project Officer: Marshall Dick
Phase: II
Project Period: September 1999 - September 2001
Project Amount: $224,715
Research Category: Clean Air
Project Summary:
Project Description:
Atmospheric Glow Technologies (AGT) proposed to combine the proven sterilizing
capabilities of the patented One Atmosphere Uniform Glow Discharge Plasma
(OAUGDP) with electrically enhanced filtration to create a system to dramatically
improve the quality of indoor air. The success of this effort will provide
an economical and practical means of reducing airborne pathogens including
viruses, bacteria, and molds. This will lead to an improvement in the health
and productivity of building occupants.
Summary of Findings:
A room-sized plenum was designed and constructed to provide a model
for a building heating, ventilation, and air conditioning system. Initial
studies were performed to establish all operating parameters to be used.
Microorganisms were aerosolized into the test plenum with an atomizer,
which served to uniformly load the microorganisms across the filter. Application
of a direct current field across the filter face resulted in a substantial
increase in capture efficiency. The capture rate for Staphylococcus aureus
improved 450 percent, while the capture rate for representative viral particles
(bacteriophage FX174) increased 900 percent. Efficacy testing demonstrated
that filters loaded with 1 x 106 bacterial cells or viral particles were
sterilized in as little as 15 seconds. Intermittent exposure of filters
to the plasma during long-term testing revealed no decrease in capture
efficiency. Likewise, there were no negative effects observed on the electrodes.
An interesting finding of this effort was the phenomenon of sterilization
of a catch filter located downstream of the plasma. In this situation,
the filter was exposed to the reactive oxygen species created by the plasma,
but not to the ultraviolet light or strong electric field associated with
direct plasma exposure. A 15-second sterilizing exposure across the primary
filter resulted in a reduction of 99.999 percent of the organisms located
downstream.
Conclusions:
The significance of a single device that both improves capture efficiency
with no substantial pressure drop while simultaneously sterilizing the
filter against any captured pathogenic organism cannot be overstated. This
technology will provide a safe, highly efficient, and more cost-effective
means to eliminate disease-causing and contaminating microorganisms from
indoor air streams. AGT's filtering system will allow residential, commercial,
and institutional building owners/managers to avoid sick building syndrome
liabilities and afford air quality solutions that previously were available
only to the more stringent "clean room" environments. This technology
addresses today's growing air quality issues and regulations pertinent
to microorganism-sensitive industrial processes and the health and well
being of individuals and the environment.
Publications:
None.
Commercialization Keywords:
Indoor air quality, atmospheric plasma, filtration, sick building syndrome,
OAUGDP
Relevant Web Sites:
Phase
I Abstract
Phase
II Abstract
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