PCO Air Purification

Maintaining Healthy Indoor Air Quality
by Dr. Truitt

Asiet, Inc. provides precisely designed state-of-the-art equipment for the remediation, improvement and maintenance of indoor air quality for almost all buildings including residential, commercial, agricultural, educational, food service, medical, elderly care and other facilities.

Maintaining Healthy Indoor Air Quality by Dr. Truitt

Considerations for maintaining healthy indoor air quality (IAQ) becomes of essential importance as our buildings inevitably become more tightly constructed for energy and cost efficiencies. Routine usage over time will introduce into a building’s heating, ventilation and air conditioning (HVAC) system accumulations of pollutants in the form of volatile organic compounds (VOCs) through the off gassing of building materials, furniture, flooring, cleaning chemicals, etc. as well as from outside contamination. Microorganisms and pathogens including viruses, bacteria, fungi and molds will almost inevitably invade and colonize in a building’s HVAC ductwork system. Current research shows that people are spending as much as 90% of their time in buildings, consequently breathing varying degrees of pollutant-laden air recirculated by the HVAC system.

Contamination and Remediation Challenges
Unfortunately, a building's IAQ problems are seldom recognized until becoming apparent in health issues of the building's occupants, (first and most commonly in children and the elderly), in reduced productivity of office workers, (usually due to broader conditions collectively referred to as sick building syndrome (SBS)), or even worse, in visible manifestations of mold growth.

By the time of such obvious detection, physical remediation of a severely contaminated building and a return to an acceptable air safety level may very well become the most expensive IAQ cost challenge faced by building management and owners.

ASITER, Inc. provides both portable and permanent equipment to virtually eliminate airborne pathogens and VOC's generally achieving pollutant destruction rates as great as 99% in all it's past remediation and correction applications.

Specific types and numbers of contaminants affecting a building's IAQ are obtained by an initial air sampling to determine an exact concentration of a toxin expressed in parts per million (ppm) and compared to the Environmental Protection Agency (EPA) mandated safe acceptable ppm level (or other governmental entities having jurisdiction over health, safety and welfare.)

Very basically, a successful remediation application is simply an expression of the numbers:
Initial air sample (ppm) > EPA’s standard (ppm) ≥ Maintenance / treated air samples (ppm)

Legionnaires Disease
for Disease Control’s (CDC) findings in Philadelphia, most states began licensing HVAC contractors to hopefully assure better and healthier mechanical installations.

In 2015 we are again confronted nationwide with outbreaks of Legionnaires disease with deaths in VA hospitals in Illinois, prisons in California, the city of New York and state of Florida. This is a result of almost forty years of complacency toward indoor air quality issues because they are not something normally visualized, rather basically out of sight and out of mind.
It was the first known cases of infection by the Legionella bacteria in Philadelphia resulting in the outbreak of Legionnaires Disease following the American Legion Convention there in 1976 that pointed to the building’s HVAC system, as the means of transmission of diseases. Legionnaires Disease is simply not transmitted from individual to individual.

Following the Center

Out of Sight & Out of Mind
In an early level civil engineering class the author participated in an assignment involving the calculation of the amount of lead deposited daily aling a short stretch of California freeway from exhaust emissions of vehicles when leaded gasoline was in common usage. The amounts of deposited lead calculated were not simply just pounds per day, or even hundreds of pounds per day but rather an alarming amount of tons per day, and all concentrated on just a short stretch of right-of-way.

More alarming was the fact these tons of lead particles were deposited in engineered grading and drainage structures designed to efficiently carry run-off water from the right-of-way directly into water courses, creeks, rivers and underground recharge areas and contaminating those waters. I submit to you those tons of lead particles were too small to be seen, hence out of sight and out of mind to the average person. Fortunately, engineering has years ago delat with those emissions and environmental problems.

A result that can be seen is an automobile’s tailpipe dripping water due to the exhaust system’s catalytic converter reducing harmful emissions to its benign constituents, CO2 and H2O.

Asiet, Inc.’s approach to perfecting indoor air quality is by using Photocatalytic Oxidation (PCO) which is somewhat similar to an automobile’s catalytic converter.

If an air stream is treated only with ultraviolet light, microorganisms are simply sterilized. They will continue to live, eventually die, and decompose naturally. This natural decomposition process produces mycotoxins that are the cause of diseases when spread by the HVAC ductwork. With PCO, ultraviolet light is focused on a metallic oxide surface that produces a field destroying VOC's and microorganisms immediately reducing them to CO2, H2O and ash. This immediate reduction totally eliminates the harmful mycotoxins. One does not see the contaminants contained in a building's HVAC ductwork so this too is usually and out of sight and out of mind situation.

Preventive Solutions
The current outbreaks of Legionnarie's Disease after forty years of awareness of its existence is truly inexcusable. All the engineering answers are available, tried and proven. They are far more cost effective when prevented rather than remediated.

While there are mechanical engineers, industrial hygienists, HVAC professionals and others knowledgeable in indoor air quality they exist around the periphery and are usually voted down by building owners and managers trying to maintain a budget. 

ASIET, Inc. offers complete programs from prevention to remediation.

ASIET, Inc. has been around since before 9/11.

Confidentiality and Reporting Challenges
Reporting on ASIET, Inc.'s previous endeavors, all of which have been remarkably successful, is limited due to the necessity of confidentiality requested by most all of the entities that require ASIET Inc.'s expertise. According, the circumstances related below are without specifics:

- Scenario 1: A State supported living facility was having an almost epidemic outbreak of bacterial conjunctivitis within its infirmary requiring incidences of quarantine; numerous cases were reported over a three week period and the facility faced shut down by the Health Department if problems were not immediately resolved and brought into compliance. A public invitation to bid was won by ASIET, Inc.'s initial company. 

The infirmary's HVAC system included three Carrier 10,000 cubic feet per minute (CFM) air handling units (AHU's ) in a common mechanical room that had been installed in 1961. All three units were run continually and very well maintained (though cobwebs, spider webs, and inches of dust heavily lined upper portions of the plenums into the ductwork). The AHU's were outfitted with both ultraviolet germicidal irradiation (UVGI) lamping and specially designed metallic oxide screens installed on the downstream side of the system effectively transforming the cavities of the AHU's to perform a dual function as photocatalytic oxidation (PCO) reactor chambers. Minimal modifications to the Carrier AHU's was a primary request of the facility management.

Similar retro-fit was also made on two Trane Model #YC rooftop units serving a dormitory under quarantine and both operating 4,000 CFM.

Initial samples were taken from contaminated filters in the infirmary's AHU's for culture and determination of numbers and types of microbes. Samples were taken each time filters were replaced thereafter. Cultures and evaluations were performed under the auspices of Dr. John Zak of Texas Tech University's Department of Microbiology.

Result: Only two other cases of infection were reported within the infirmary before the modifications were complete. Installation personnel working in the large AHU's had to be taken to a local ER for treatment of severe conjunctivitis immediately upon completion of the installation work. No incident of infection or quarantine has occurred at the facility since the ultraviolet-oxidation treatment equipment has been operative. The infirmary remained open and subsequent regular Health Department inspections reported far superior compliances and performance. 

When the same installation personnel returned for the first filter change and equipment inspection an unexpected result was discovered in that the cobwebs and dust lining the plenums and ductwork were gone and the sheet metal was almost shiny as if new. Nurses reported the medicinal smells and foul odors that permeated the aging building for years had dissipated and the air had a clean, fresh smell. (It was further reported when popcorn was microwaved in the break room it could now be smelled throughout the entire building which had never been noted previously.)

Scenario 2: A very popular, small-town family owned business involved a BBQ restaurant, a high volume public meat market and a public meat processing plant; the meat processing plant was encountering severe issues of Listeria transmission from raw to finished meat products. The processing plant required continual cleaning that was, at best, only marginally successful in keeping the facility open. The processing plant was on the very brink of being completely shut down by the United States Department of Agriculture (USDA) inspectors. The USDA was seriously addressing the issue of Listeria nationwide at the time; guidelines were emerging but not published at that particular date.

Result: Asiet, Inc.’s initial organization designed and installed four individual ceiling mounted units of 2,700 CFM each hung at strategic locations in the processing facility. The treatment scheme was almost identical to that described above in the State School facility with UVGI lamping but having the metallic oxide screens housed in hanging cabinets to operate as a recirculating, open-loop PCO reactor system. USDA inspectors were completely astounded and impressed that the threat of Listeria transmission was removed almost overnight once the system was operational. An incidental benefit was that the usual unpleasant smell of blood and guts associated with meat processing plants was eliminated as long as the treatment reactors were allowed to run either continually or on a timely cycle.

Subsequently, only a single incident causing concern would later arise but this was due strictly to the owners failing to maintain the equipment. Once the equipment was serviced and brought back up to its designed operational level no other problems have developed with regard to USDA compliance. (Complacency toward maintenance often becomes problematic as ultraviolet/oxidation equipment users become accustomed to the system running so quietly and effectively while being both out of sight and out of mind.)

Scenario 3: An out-of-state independent school district discovered evolving mold problems throughout most of its buildings; shutting down for remediation throughout the entire system in the regular school year is neither an immediately viable cost nor timing option. The issue is currently marginal, though serious, and school administrators are concerned public notification of the matter might cause overreaction with probable parental panic based on similar situations occurring elsewhere in that state.

Result: An industrial hygienist was employed full time by the school district; initial treatment was fumigation of the HVAC systems as permissible to assure air quality and students’ well-being. However, leaky, damp buildings along with other construction deficiencies contribute to re-infestations and must also be addressed. Asiet, Inc. was brought onboard to provide portable air scrubbing equipment running as necessary in conjunction with the district’s interim program of constant air sampling to insure it remains within EPA’s IAQ guidelines. This enables the school to maintain classes open until appropriate ultraviolet/oxidation components are designed for permanent installation in the HVAC ductwork, an overall construction schedule decided, and funding available.

All ASIET Air Purifiers Come With This Warranty

UV Light Hazard | ASIET Air Purifiers | Just Good Clean Air
SAM System for Award Managment | ASIET Air Purifiers | Just Good Clean Air
Choice Partners | ASIET Air Purifiers | Just Good Clean Air

AIR Purification


Contact Us