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1. Why are researchers in many countries trying to develop higher levels of respiratory protection? There are many contaminants that challenge the respiratory system, including dust, bacteria, fungi and viruses. These particles can range in size from 0.02 microns (µm) to 100 µm, as is illustrated in Figure 1. NIOSH requires that N95 respirators filter out salt particles at 0.3 microns for 20 minutes with a minimum efficiency of 95%. While most dust particles, bacteria and fungi are filtered out by commercially available N95 respirators, viruses fall below the 0.3 microns size of the NIOSH test salt particles and can escape filtration. However, they have historically been better than other forms of disposable protection.  Click picture to enlarge Kowalski and Bahnfleth (1998). Airborne respiratory diseases and mechanical systems for control of microbes. Heating, Piping, Air Conditioning. July: 34-48. 2. I thought that 0.3 microns was supposed to be the hardest sized particle to filter out of an air stream? It is a long-held belief by many scientists that 0.3 microns is the most difficult particle size for respirators to filter. Truth is, it used to be—back when masks, respirators and other air filters worked by solely mechanical means. Filtration was accomplished by combination of impaction, gravitational attraction and diffusion (van der Waal's forces). It was found that particles larger than about 0.3 microns were filtered out of the air stream by the first two mechanisms. Particles smaller than 0.3 microns were so small that they were buffeted by molecules in the air causing extremely erratic movements (Brownian motion) which increased the likelihood of their "bumping" into filter fibers and being trapped. Therefore, particles larger and smaller than 0.3 microns were easier to filter than 0.3 µm. That is why NIOSH rightly chose 0.3 microns for challenging mechanical air-filtration devices—that is until electret media came along. One of the problems with mechanical air filtration is that it is extremely difficult to produce highly efficient filters without making it almost impossible to breathe through. To solve this problem, researchers found that placing a charge on the material increased its ability to attract and capture particles (viable and non-viable). Conceptually, it was like adding a polarized magnet to the fibers that added charge attraction as a particle capture mechanism. These charged materials are called electrets or electret media. There are several manufacturing methods available to incorporate this charge. Some are more effective and less affected by degradation than others. Compared to the same filtration media that has not been charged, electret media is far more effective at capturing all sizes of particles, so the overall efficiency is increased. However, after extensive testing, it was determined that there was a shift in the most penetrating particle size from 0.3 to 0.1 microns; making 0.1 micron particles (non-biological or biological) more appropriate for test challenges. Several recent studies are referenced below. In addition to particle size studies with nonviable particles, Kowalski performed studies with numerous bacteria and viruses demonstrating their ability to escape capture. These are charted in his paper, referenced below. However, the NIOSH test is still 0.3 microns and for only 20 minutes. There are many ways to charge filtration materials. Some are better than others at creating an effective charge and at maintaining that charge. Factors such as high humidity, liquids, high temperature, debris loading, aerosolized oil or fat as well as alcohol can discharge, degrade or neutralize the charge on most electret materials. When the electret media charges are neutralized, the overall filtration efficiency drops and the mechanism of filtration shifts back to mechanical. As disposable respirators utilize electret media, they should be evaluated with 0.1 micron particles as the most penetrating size. In a later question, we will point out that the development of new technologies highlights the importance of viral filtration testing with well defined test parameters is also critical. Unfortunately, regulations to ensure effective respiratory filtration performance against biological particles have not kept pace with technological advances in respiratory protection. Richardson AW, Eshbaugh JP, Hofacre KC, Gardner PD. Respirator filtration efficiency testing against particulate and biological aerosols under moderate to high flow rates. August 2006 ECBC-CR-085 USS Army Research, Development and Engineering Command; Edgewood Chemical Biological Center, performed Battelle Memorial Institute Balazy A, Toivola M, Reponen T, Podgorski A, Zimmer A, Grinshpun SA. Manikin-based performance evaluation of N95 filterinf-facepiece respirators challenged with nanoparticles. Ann. Occup. Hyg. 2006; 50(3):259–269. Ba1azy A, Toivola M, Adhikari A, Sivasubramani SK, Reponen T, Grinshpun SA. Do N95 respirators provide 95% protection level against airborne viruses, and how adequate are surgical masks? AJIC 2006; 34(2):51-57. Heimbuch BK, Wander JD. Bioaerosol challenges to antimicrobial surface treatments: enhanced efficiency against MS2 coliphage of air filter media coated with polystyrene-4-methyltrimethylammonium triiodide Air Force Research Laboratory, Airbase Technologies Division, February 2006; AFRL-ML-TY-2006-4527. Kowalski WJ, Bahnfleth WP, Whittman TS. Filtration of airborne microorganisms: modeling and prediction. ASHRAE Transactions Research 1999; 105: 4-17. Myers DL, Arnold BD. Electret media for HVAC filtration applications. INJ 2004; 12(4):45-54 (web version published in 2003) Back to Top 3. How many viruses does it take to cause a respiratory infection? The number of viruses required to cause infection is referred to as the infectious dose. The infectious dose can be altered by variations in the environment, the health of the individual, the route of exposure and the biological properties of the virus. However, general infectious dose levels have been established in scientific literature for several viruses as displayed in Figure 2. Since many of these extremely small microbial threats can infect an individual with as few as 1-100 microorganisms, NIOSH N95/P95, EU FFP2 and AS/NZS 1716 disposable respirators may be inadequate to protect the wearer during airborne viral exposures. It should be noted however that even a respirator that provides effective viral filtration performance and a tight seal around the face to prevent unfiltered air from leaking into the face piece can only minimize but may not eliminate the risk of contracting infection, illness or disease caused by airborne viruses. The key is to minimize the risk to the greatest extent possible.
Back to Top 4. Why do WHO and CDC recommend N95 respirators (or their equivalent)? NIOSH approved N95 respirators have historically been one of the best disposable respiratory protection devices available. They were originally created for worker protection from industrial dust and particulates, as the requirements of the N95 certification test imply. After years of use in industry, they were introduced into the healthcare environment to protect caregivers exposed to pulmonary tuberculosis, a highly infectious disease. As tuberculosis bacilli (Mycobacterium tuberculosis) measure 1-5 µm in length and 0.2-0.6 µm in width, they are effectively filtered by NIOSH approved N95 respirators. Filtration efficiency and the fit of the respirators are important factors as it only requires the inhalation of a few TB bacilli to establish an infection. Because NIOSH approved N95s respirators have traditionally been effective in TB control, they were recommended by the CDC and WHO for other biological particles such as SARS and avian influenza. However, the NIOSH certification process does not include an evaluation of viral filtration efficiency! Furthermore, recent studies suggest that NIOSH approved respirators do not exclude biological particles less than 0.3µm in size with 95% filtration efficiency as it was historically assumed (Balazy A, et.al.., AJIC 2006;34(2):51–57). Today, we face ever increasing threats of new and emerging pathogens, pandemic influenza and bioterrorism. Figure 2 emphasizes that highly pathogenic viruses are a fraction of the size of the TB bacilli. Because many of these extremely small microbial threats can infect an individual with as few as 1-100 microorganisms, N95 disposable respirators may not be adequate to ensure that the wearer is protected during airborne viral exposures. Back to Top 5. How are airborne viruses spread between humans? An average sneeze (Figure 3) produces about 500,000 droplets, while a cough may produce over 1,000. Even speaking produces a bio-aerosol (Figure 4). As noted in Figure 5, the droplet composition initially propelled from the mouth ranges in size from about 1,000µm to less than 0.5µm with an average of 10µm for all three forms of human production. However, these droplets rapidly evaporate to their core nuclei ("naked" microorganisms) as displayed in Figure 5. This is significant as it means that a large proportion of the initial propelled droplets will rapidly evaporate to the microorganisms they contain. These nuclei, as they are referred to, can stay suspended in the air currents for long period, travel long distances, and can be small enough to evade capture by N95 respirators. Data presented in response to questions following this section demonstrate that even N95 respirators let a significant number of infectious particles pass through the filtration media when challenged with these "naked" viral nuclei. Back to Top
6. Are there test data comparing Triosyn Respirators with N95 respirators? The result of numerous studies, some of which are shown below, demonstrate the enhanced filtration efficiency of Triosyn® Disposable Respirators over other N95 technologies. No one knows for certain the number of airborne viruses that would be encountered in the event of a pandemic influenza, SARS, bioterrorist attack or even when exposed to a more routine airborne infection such as chicken pox. However, it is has been thought to be below 10,000 plaque forming units (pfu interpreted as the number of viruses) per square meter. Studies often exaggerate the level of viral challenge exposure so that the results can highlight the differences in filtration performance. The study in Figure 6 was performed using the 0.023µm, MS2 virus, a coliphage internationally used for bio-aerosol testing. This study was performed with a respirator face velocity equivalent to 85 liters per minute (LPM), the same flow rate used by NIOSH to represent the breathing effort during heavy work activity. It should be noted that the N95 respirators allowed 100 to 10,000 times more MS2 viral particles to penetrate the filtration media than the Triosyn filter media permitted.  Figure 6. Flow: 85 LPM equivalent — Duration 8 hours Study M05-0698-0705 Challenge average about 50,000,000 virus particles (Note: Triosyn iodinated resin is refered to as: POLYSTYRENE-4-METHYLTRIMETHYLAMMONIUM TRIIODIDE) It may appear that there is little difference between a few percentage points of filtration efficiency. However, the chart displayed as Figure 7, helps to show what a difference a few percentage points can make. The infectious dose of most airborne infections is usually estimated at 10 to 100 viruses.  Figure 7. Theoretical penetration of viruses based on exposure and percent filtration.  Figure 8. Flow: 85 LPM — Duration: 90 minutes. Study M06-0031.0042.0043.0058 The Triosyn® filter media has also been tested against the SARS Coronavirus by independent laboratories as shown in Figure 9. This study utilized levels of SARS viral exposure thought to more closely represent potential indoor airborne exposure. The aerosol was delivered with a collision nebulizer in a Biosafety Level 3 Laboratory. To reduce the potential for exposure, 47 mm swatches of the respirators were utilized and the face velocity adjusted to compensate for sample size.
Figure 9. Testing With SARS Coronavirus. Study: Health Canada 04.24.04 Back to Top 7. Do Triosyn® Respirators maintain their enhanced performance over extended exposure? Yes. There are numerous studies comparing the filtration efficiency of the Triosyn respirators to a plethora of commercially available N95 respirators. The results illustrated in Figure 10, demonstrated that Triosyn respirators consistently provided a much higher level of filtration efficacy over time when challenged with aerosolized MS2 virus. This is in sharp contrast to the performance of the N95 respirator which started with a lower level of protection than the Triosyn respirators and rapidly deteriorated further from there. It is also important to note the standard deviation (represented by the error bars) shows the wide variation in respirator to respirator performance of this N95 respirator brand tested compared to the lack of performance variation demonstrated by the Triosyn respirators. The performance of other N95 disposable respirators may vary. Back to Top  Figure 7. Flow: 85 LPM — Duration: 8 hours Study M05-0699/M05-0702 The study presented in Figure 11, shows the results of a continuous challenge of approximately 5,000 viral particles per hour over a 24 hours period. Needless to say, wearing a respirator for 24 hours is not a realistic scenario, however it does help to further emphasize the difference in extended filtration performance between Triosyn respirators and two commercially available N95 respirators.  Figure 11. Flow: 85 LPM — Duration: 24 hours Study M05-0702 & M05-0704 8. What labs have tested the Triosyn technology? For the past 13 years, the Triosyn Corp.'s R&D Team has collaborated with the following world renowned independent testing laboratories, governmental entities and military institutions to create and design leading edge technologies and/or perform evaluative testing protocols. Laboratories include:
Back to Top 9. What is Triosyn®-Resin and why is it incorporated into the respirator media? Triosyn® Resin is an innovative, patented, iodinated resin (Figure 12) registered with the EPA. It is incorporated in the Triosyn® disposable respirators to preserve the filter media and thereby prevent the degradation of the media properties under normal conditions of use over many hours. Triosyn interacts with viruses, bacteria, protozoa and fungi through a demand-release mechanism activated by the presence, type and population density of the microorganisms. Triosyn resin incorporates a complex tri-iodide (I3¯) molecule that releases molecular iodine (I2) when in close proximity with the microorganisms. This prevents growth, replication and migration of respirator-captured microorganisms. Migration can be a significant cause of performance failure for standard respirators as moisture builds, engulfs and suspends live organisms on the fibers and dumps them back into the air stream when they reach critical mass. Triosyn also preserves the electrostatic charge on the filtration fibers of the respirator, maintaining the effectiveness of the capture and retention of microbial threats over extended periods of time.  Upon contact with the media, the microorganisms activate the Triosyn demand-release mechanism. An increased concentration of microorganisms results in a larger number of Triosyn resin sites simultaneously releasing molecular iodine. The molecular iodine then oxidizes the microorganisms, rendering them harmless. The release mechanism, along with the inherent properties of the I2 molecule, combines the broad spectrum activity of I2 with very rapid effectiveness. When the source of iodine demand is eliminated, the Triosyn resin immediately returns to its resting state, preserving stored iodine until reactivated. Back to Top 10. Has the Triosyn Technology been incorporated into other products?  Back to Top 11. Against which microorganisms has the effectiveness of the Triosyn Technology been tested?
 Figure 15. Triosyn Respirator construction Back to Top 13. What are the benefits of the carbon layer? An activated carbon layer is incorporated in the filtration media to provide a means of reducing nuisance organic vapors and odors. This is a novel and significant advantage for individuals working in disaster zones and other areas where respiratory protection is recommended. Back to Top 14. How long can the respirator be stored? Kept sealed in their individual packages, Triosyn® Disposable Respirators with Antimicrobial Protection have a shelf life of 5 years. Back to Top 15. How well do Triosyn® Disposable Respirators fit the wearer? Triosyn® Disposable Respirators were tested with regard to fit along with a leading commercially available NIOSH approved N95 respirator by an independent Fit Testing Laboratory. Testing was performed using the standard OSHA protocol on a test panel of 25 persons. Fit testing was assessed for each respirator model on each test subject. The tests demonstrated that the Triosyn® disposable respirators not only meet the OSHA Fit Test standards requirements but also exceeds the fit factors of the leading commercially available disposable respirator.
Triosyn(R) Disposable Respirators with Antimicrobial Protection Built In 16. Are Triosyn® Disposable Respirators used by First Responders? Triosyn® respirators are used by many First Responders both nationally and internationally. All three models – Triosyn T-3000, Triosyn T-5000 and Triosyn T-5000V – are on the Approved Equipment List (AEL) for Personal Protective Equipment (PPE) in the Department of Homeland Security's Responder Knowledge Base Program (RKB). The RKB is a web-based objective information service for the emergency responder community funded by the DHS and used by over 40,000 State and Federal subscribers. www.rkb.mipt.org Back to Top 17. What is known about iodine allergies? Iodine allergies have been purported to result from hypersensitivity reactions to iodinated drugs or consumption of seafood. Hypersensitivity reactions to iodinated drugs are rare and most of the literature reported cases investigating this issue are unable to establish a direct causal relationship linking iodine as the responsible chemical for these reactions. For example, based on the literature review by Dewachter et al (2005), povidone, and not iodine, is probably the compound responsible for allergic reactions to the skin antiseptic povidone iodine. The same is true in the case of allergic reactions to iodinated contrast media, where the iodine atom has not been shown to be the allergenic determinant responsible for these reactions. Likewise, it is also common to associate allergy to seafood with allergy to iodine. However, it appears that protein M or tropomyosin are the allergens responsible for patient sensitization involving fish and shellfish allergies (Dewachter et al, 2005) and not the iodine molecule itself. In summary, it appears that the term "iodine allergy" is a misnomer commonly used in the medical field, since it does not correspond to an identified clinical entity. Thus, asking a patient if he/she is allergic to iodine is a question that should be avoided because the question is not relevant. It is important to separate the chemical element "iodine" from the molecule which contains it; given that it is not iodine in itself which provokes the allergic reaction, but the carrier molecule or solution. It is also important to note that salt iodization is a worldwide recognized procedure to prevent iodine deficiency disorders. However, there has been negligible evidence of any adverse effects, such as allergic reactions, associated with iodine intake (WHO, UNICEF, ICCIDD, 1996). A summary of the research literature available on the incidence of hypersensitivity reactions to iodine is presented in Figure 16.
Figure 16. Additional references: Brown & Mutter, 2003; Dewachter & Mouton-Faivre, 2005; Sato et al., 2004; van Ketel & van den Berg, 1990 Back to Top 18. What is the cost effectiveness of this technology? When evaluating criteria for selecting personal protective equipments such as a respirator and looking at cost, it is important to examine what you are paying for. Will it be effective in preventing the penetration of airborne biological particles including viruses? Will it maintain a high level of filtration efficacy during the entire use period? When making purchasing decisions for respiratory protective equipment, the points listed below should be considered. If it is worth buying a respirator, then make certain it provides the level of filtration efficiency that is needed throughout the time the respirator is worn. A disposable respirator must provide:
Safe Life™ Disposable Respirators with Triosyn® Antimicrobial Protection provide the ultimate respiratory protection against microbial threats. Back to Top 19. What regulatory approvals have been received? Environmental Protection Agency (EPA):
All studies and references provided upon request |
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