Masking The Problem Makes Sense! Phil Maybee, CAFS
H1N1 - SARS - Avian Flu what is the next generation of airborne pathogen that we will be required to learn about? A few years ago we had the realization that TB was back in greater strength than ever before - with strains that now resist all medication treatment procedures. What options do we have against the airborne transmission of the various threats as they are identified?
Filtration, ultraviolet germicidal lights, and other technologies have been developed to remove these contaminants from the airstream. The issue with this is that the contaminants must travel through the duct systems back to Air Handling Units before they can be treated. This means maintenance personnel can be exposed to the contaminants in the service of equipment and anyone between the AHU are in the pathway of contamination.
Protective masks may be an advantage and are required in some airports and public places around the world but are slow to gain popularity in the US. However, it is possible to have a comfortable face mask that adheres to the skin with little restriction to facial movement, speech, and respiratory effort that will remove greater than 99% of all airborne pathogens. There are no straps around the head, valves to align or parts to shape. In areas of higher risk it makes sense to protect ourselves rather than play roulette with the potent "bugs" that can ruin a trip or our health for longer terms.
The protective masks work in BOTH inhale protection for the workers or exhale protection when worn by infected patients. The seal method allows the filtration efficiency to work in either direction.
This same technology that is used currently in N99 masks is also possible for the return air grilles in ducted HVAC systems to remove the disease causing droplet nuclei or other viral, bacterial, or particulate contaminants before they can enter the system supplying air to the facility. This simple effective system removes greater than 99% of all airborne particles at near HEPA efficiency right at the return air grille. They can be serviced easily from room side and provide a high level of removal efficiency than most filtration elements installed in the HVAC equipment.
The key to this technology is a synthetic lofted media that is greater than 99.5% on 0.1 micron size particles at airflows typical to return air grilles. Human breathing is much lower air velocities and as thus will see increased removal rates. While improving the filter efficiency in the AHU can be of great value - prevention of the harmful agents ever reaching that system is far more effective - whether it be AHU fan or a set of lungs.
