Final Report: Indoor Air Biocontaminant Control by Means of Combined Electrically Enhanced Filtration and OAUGDP Plasma Sterilization

EPA Contract Number: 68D99025
Title: Indoor Air Biocontaminant Control by Means of Combined Electrically Enhanced Filtration and OAUGDP Plasma Sterilization
Investigators: Kelly-Wintenberg, Kimberly
Small Business: Atmospheric Glow Technologies
EPA Contact: Manager, SBIR Program
Phase: II
Project Period: September 1, 1999 through September 1, 2001
Project Amount: $224,715
RFA: Small Business Innovation Research (SBIR) - Phase II (1999) Recipients Lists
Research Category: Air Quality and Air Toxics , SBIR - Air Pollution , Small Business Innovation Research (SBIR)

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/Accomplishments (Outputs/Outcomes):

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.

Supplemental Keywords:

Indoor air quality, atmospheric plasma, filtration, sick building syndrome, OAUGDP., RFA, Scientific Discipline, Air, particulate matter, Chemical Engineering, air toxics, Environmental Chemistry, Chemistry, Biochemistry, indoor air, tropospheric ozone, Engineering, Chemistry, & Physics, Environmental Engineering, ambient air quality, particulates, biofilter , electrostatic removal, electrically enhanced filtration, biocontaminant control, air pollutants, stratospheric ozone, aerosol particles, ambient air, filtration, filtration technology, biofilter, bacteria filtration, air pollution, indoor air chemistry, particulate exposure, plasma sterilization, plasma filter, biocontaminants, OAUGDP, aerosol, indoor air quality, biofiltration systems, air quality, ultrafine particles, ambient pollution control


SBIR Phase I:

Indoor Air Biocontaminant Control by Means of Combined Electrically Enhanced Filtration and OAUGDP Plasma Sterilization  | 1999 Progress Report  | Final Report