Air Filtration is About More than Dust
Air filtration is the process of separating dispersed particles from air by means of porous media. Air filtration protects the human respiratory system while indoors, as well as, protects the HVAC system. Usually mechanical filtration is used to reduce contaminant concentrations, which vary depending upon the nature of the application and location. The s=effectiveness of the system depends on its ability to capture the right contaminants in the right quantity at the lowest resistance to the airflow.
It is Not Only Dust
Airborne particles are all around us — they come in many different forms, such as grit, dust, smoke, fumes, or mist, smog and fog.
The types of particles are many: mineral dusts (containing crystalline silica – e.g. quartz); coal and cement dusts; metallic dusts (such as lead, cadmium, nickel, and beryllium); other chemical dusts (such as bulk chemicals and pesticides); organic and vegetable dusts (such as flour, wood, cotton, tea and pollens); and biohazard dusts (such as viable particles, molds, and spores).
Human activity is not the only cause. Things such as weather conditions and the natural environment can cause windblown, construction, or fugitive dust, which all contribute to air pollution. High winds raises dust from areas of dry, loose, or disturbed soil. Forest fires such as currently in California and Oregon can cause almost apocalyptic damage to air quality across multiple state lines.
The air we breathe is full of these microscopic particles, which adversely effect health, particularly for the elderly. Some particles you can see and some are in the order of several nanometers to several micrometers in size.
An average adult breathes 17,000 liters of air daily, so collectively a low concentration of airborne contaminant represents a large quantity entering the body. Every day, billions of particles are inhaled with the ambient air by every human being. From the toxicological point of view, all particles smaller than 10 μm in diameter have the potential of being biologically active in susceptible individuals.
The case against dust and air pollution is not confined to their unpleasantness. Silicosis, caused by inhalation of minute particles of silica, and other forms of pneumoconiosis (caused by inhalation of dust, including, asbestos, coal, metallic particles, decaying organic matter from vegetation, or bird droppings) are serious pulmonary diseases. In short, many airborne particles are the source of disabling or fatal illnesses. There is no need to question the need for air filtration and cleaning.
Our Modest Filter Selection
Air filtration is considered the most common method for cleaning air and is used in many diverse applications. Most filtration relies on single-stage filtration, which is usually 1 or 2 inches thick, a disposal filter, or a washable metallic filter. When HEPA filters are used, they have to be preceded to a minimum of three filtration stages, namely, fresh air, prefiltration, and fine filtration.
In recent decades, more emphasis has been placed on preventive maintenance (PM) filtration with medium efficiency and minor attention given to bioaerosols and gaseous filtration. Future air filtration plans would need to investigate new technologies to capture bioaerosols and gaseous contaminants. With the recent impact of the novel SARS-CoV-2 virus, air filtration requires not only new tools, but also new attitudes, particularly as knowledge about the current COVID-19 coronavirus pandemic is evolving.
Air Filtration Selection
There is a lot of emphasis on using HEPA filters currently to combat the SAR-CoV-2 (C0Vid-19) virus. Numerous recommendations demand a higher class of HEPA filter to enhance the air quality. Therefore, appropriate filter selection, operation, and maintenance are of paramount importance. Other challenges confronting filter performance include: upstream and downstream flow, non-uniformity of filter pleats, filters with various media properties, cartridge design, and filter installation. These parameters can influence the efficiency of the filter and its sustainable performance.
Raising the Bar on Air Filtration Efficiency
Increasing the gas velocity shortens the particle dwell time inside the filtration medium. Consequently, it reduces the possibility for a particle-to-fiber contact, and, therefore, the efficiency may be compromised. When the velocity is increased, particles can re-entrain into the airstream and therefore lower the overall efficiency. In highly efficient filters, this could mean the filter under test may fail to classify as HEPA. Conversely, the same filter could achieve higher efficiency than the rated one if subjected to a lower flow rate.
The Preventive Approach
While it is widely accepted, that CoVid-19 is transmitted person to person, it can deposit onto surfaces due to people breathing, sneezing, and so on. This allows it to get into HVAC systems, especially when air is extracted from populated rooms.
One methodology currently proven to be effective in killing Covid-19 is bi-polar ionization (BPI). Airflow passes through the BPI tube which energizes the air to form bipolar — positive and negative — air ions. Ionization tubes clean the air without using unsafe chemicals or creating any unwanted byproducts.
The airflow distributes the energized ions into all of the spaces served by the duct system in an in-duct installation, or into the applicable space if a standalone unit is used. It easily integrates into an existing commercial HVAC system.
Unlike most air filtration systems, BPI seeks out and neutralizes the contaminants at their source. It doesn’t wait for the pollutants to find their way into the filter within the air handler. Instead, the BPI created air ions go directly to the contaminant in the space where you are breathing, just as in nature.
As a representative of AtmosAir Solutions, we recommend their BPI systems to kill CoVid-19. Their product is the solution that addresses both air quality and energy costs — a technology that attacks odors, mold, VOCs, bacteria, allergens, dust and Sick Building Syndrome. With AtmosAir™, you’ll also get Guaranteed Energy Savings™ without relying on dangerous chemicals or metals, or creating toxic byproducts.
Access, Inc practices what “… we preach by installing Atmosair BiPolar ionization units in the four furnaces that serve the office…”. While CoVid-19 is the primary reason, here are just some of the secondary reasons:
…The primary reason is that Atmosair units have been tested to effectively kill 99% of Coronavirus Virons but there are many secondary benefits…As quoted by Lee Heeter, President of Access, Inc. in his 9/10/2020 email to Access employees.
- Reduced dust and mold particles. Bipolar ions that bond with contaminants gain size and mass and drop to the floor, or return to the filter, making them easily cleaned from the air we breathe.
- Reduced odors. Bipolar ions break down odors at their source and eliminate them — no masking or diluting!
- Reduced VOCs (Volatile Organic Compounds). Bipolar ions break down toxic gasses and compounds from dangerous chemicals such as cleaning products, pesticides, paints, solvents, mold, mildew and more.
- Reduced bacteria and viruses. Because bipolar ions negatively affect the DNA of bacteria and viruses, you’ll protect your space’s inhabitants from illness and disease.
- Reduced static electricity. Bipolar ionization naturally neutralizes the air, eliminating static charges.
As we’ve discussed here, air filters are inadequate for non-particulates in the air space. Gaseous and bacterial pollutants can not be captured even bya HEPA filter and the use of MERV11 or higher filters. The success of any filtration system depends upon its ability to capture the right contaminants in the right quantity whilst presenting the lowest resistance to the airflow.
BPI is the new approach to indoor pollution. By creating positive and negative ions in the air space – not just the air stream – pollutants in the air space and on surfaces are controlled. In fact, 99% of the time, if you’re CoVid-19 you’re dead. Less us put a target on your IAQ today!
This article has been modified from the original which can be read in its entirety at esmagazine.com HERE.