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Decontamination of N95 filtering facepiece respirators (FFRs) is a crisis capacity strategy allowed when there are known shortages of FFRs. The application of moist heat is one decontamination method that has shown promise and is the approach approved in the Steris Steam Emergency Use Authorization (EUA). This effort examines the use of multicookers to apply moist heat, as they are available in retail stores and more affordable than methods requiring more sophisticated equipment. Four of five multicooker models examined met the acceptance criteria for the test and one model was selected for inactivation testing. Tests were performed on four different FFR models with SARS‐CoV‐2 suspended in culture media, simulated saliva or simulated lung fluid. Moist heat treatment reduced recoverable titres of SARS‐CoV‐2 virus to levels below the limit of detection in all tests. Furthermore, these four FFR models showed no loss in collection efficiency, inhalation resistance or visual damage after up to 10 decontamination cycles. Two (2) FFR models showed a slight change in strap elasticity (, Significance and Impact of the Study: The potential to decontaminate N95 filtering facepiece respirators (FFRs) contaminated with SARS‐CoV‐2 in culture media, simulated saliva and simulated lung fluid using moist heat in a multicooker is demonstrated. Furthermore, the FFR models tested did not show degradation of performance when subjected to at most 10 decontamination cycles. This approach represents a low‐cost and simple FFR decontamination method that could be considered for use when shortages exist during an emergency, such as the ongoing COVID‐19 pandemic.

The Battelle Critical Care Decontamination System™ (CCDS™) decontaminates N95 filtering facepiece respirators (FFRs) using vapor phase hydrogen peroxide (VPHP) for reuse when there is a critical supply shortage. The Battelle CCDS received an Emergency Use Authorization (EUA) from the US Food and Drug Administration (FDA) in March 2020. This research focused on evaluating the mechanical properties of the straps as an indicator of respirator fit. The objective was to characterize the load generated by the straps following up to 20 don/doff and decontamination cycles in Battelle’s CCDS. In general, the measured loads at 50 and 100% strains after 20 cycles were similar (±15%) to the as-received controls. Qualitatively, reductions in the load may be associated with loss of elasticity in the straps, potentially reducing the ability to obtain a proper fit. However, small changes in strap elasticity may not affect the ability to obtain a proper fit given the potential for variation in strap length and positioning on the head. Regardless, prior to reusing a N95 respirator, it is important to complete a visual inspection to ensure it is not damaged, malformed, or soiled. If so, it is recommended to discard the respirator and use a different one. Similarly, the respirator should be discarded if the wearer cannot obtain a proper fit during the user seal check.

In 2018, the Centers for Disease Control and Prevention reported that opioid overdose deaths (including fentanyl and carfentanil) comprised 46,802 (69%) of the 67,367 total drug overdose deaths. The opioid overdose epidemic affects Americans not only at home but also in the workplace. First responders may be at risk of opioid exposure during incidents such as vehicle searches and responses to overdose calls. To reduce direct exposure to opioids and other hazardous drugs, first responders rely in part on personal protective equipment (PPE) as their last line of defense. First responders seek guidance from the National Institute for Occupational Safety and Health (NIOSH) regarding appropriate PPE selection for potential opioid exposure. There is limited empirical glove performance data for illicit drugs. Empirical data are needed to validate NIOSH’s current recommendations regarding gloves to help prevent exposure to illicit drugs (i.e., powder-free nitrile gloves with a minimum thickness of 5 ± 2 mil [0.127 ± 0.051 millimeters]); however, no industry standard or test method currently exists for specifically evaluating PPE performance against fentanyl and its analogs. To understand the permeation qualities of gloves when challenged against fentanyl and carfentanil solutions, the ASTM International (formerly American Society for Testing and Materials) ASTM D6978–19 standard for chemotherapy drug glove permeation was adapted to test fentanyl and carfentanil hydrochloride solution permeation through twelve disposable glove models, including five models in which the manufacturers claim fentanyl protection. No nitrile glove models showed fentanyl or carfentanil permeation rates above the chemotherapy drug threshold criterion of 0.01 μg/cm(2)/min (i.e., thereby meeting the performance requirement) as calculated using the ASTM D6978–19 standard within the 240-min test. Latex and vinyl glove materials exhibited fentanyl and carfentanil permeation with permeation rates above this threshold. These findings are among the first empirical data to support NIOSH’s current opioid glove recommendations and define procedures that could be used to support industry standards for evaluating opioid permeation through air-impermeable PPE materials.

The growing threat of an influenza pandemic presents a unique challenge to healthcare workers, emergency responders, and the civilian population. The Occupational Safety and Health Administration (OSHA) recommends National Institute for Occupational Safety and Health (NIOSH)-approved respirators to provide protection against infectious airborne viruses in various workplace settings. The filtration efficiency of selected NIOSH-approved particulate N95 and P100 filtering facepiece respirators (FFRs) and filter cartridges was investigated against the viable MS2 virus, a non-pathogenic bacteriophage, aerosolized from a liquid suspension. Tests were performed under two cyclic flow conditions (minute volumes of 85 and 135 L/min) and two constant flow rates (85 and 270 L/min). The mean penetrations of viable MS2 through the N95 and P100 FFRs/cartridges were typically less than 2 and 0.03%, respectively, under all flow conditions. All N95 and P100 FFR and cartridge models assessed in this study, therefore, met or exceeded their respective efficiency ratings of 95 and 99.97% against the viable MS2 test aerosol, even under the very high flow conditions. These NIOSH-approved FFRs and particulate respirators equipped with these cartridges can be anticipated to achieve expected levels of protection (consistent with their assigned protection factor) against airborne viral agents, provided that they are properly selected, fitted, worn, and maintained.

Although not well established, mask leakage measured using submicron aerosol challenges is generally accepted as being representative of vapor challenges. The purpose of this study was to compare simulated respirator fit factors (FFs) measured using vapor challenges to those measured using an aerosol challenge. A full-facepiece respirator was mounted on a headform inside a small enclosure and modified with controlled leaks (laser-drilled orifices) to produce FFs ranging from about 300 to 30,000. A breathing machine was used to simulate breathing conditions of 1.0 L tidal volume and 25 breaths/min. A monodisperse aerosol consisting of 0.72 micron polystyrene latex spheres (PSL) was used for the reference test aerosol, and FFs were measured using a laser aerosol spectrometer. An inert gas, sulfur hexafluoride (SF6), and an organic vapor, isoamyl acetate (IAA), were used as the vapor challenges. The in-mask concentration of SF6 was measured using a gas chromatograph (GC). A GC was also used to quantify in-mask IAA concentration samples actively collected with sorbent tubes. FF measurements made with the PSL aerosol challenge were conducted in sequence with the SF6 and IAA challenges, without disturbing the mask, to yield matched data pairs for regression analysis. FFs measured using the PSL reference aerosol were found to correlate well with those measured with the SF6 (r2 = 0.99) and IAA (r2 = 0.98) vapor challenges. FFs measured using IAA tended to be higher at values below 10,000. The best agreement was observed with the inert gas, SF6. The results of this study suggest that submicron aerosols are suitable as quantitative fit test challenges for assessing the performance of respirators against inert vapors.

Over the last several years, aerosol samplers have been fielded in many locations to collect biological agents in the air, providing a sample that, once analyzed, will alert safety and public health officials of potential bioterrorism events. If a biological agent was present at the sampling location, the collector and surrounding area may be contaminated due to bioaerosol deposition, possibly posing a hazard to the technician maintaining the aerosol sampler. The technician may, in turn, serve as a source for cross-contamination to clean areas subsequently visited, potentially producing a hazard to others if transferred to indoor settings, such as a job site or analysis laboratory. To investigate our hypothesis about these potential exposure sources and cross-contamination, a study was performed to: (1) examine biological material transfer from a contaminated site to an individual; and (2) determine aerosol resuspension levels due to typical personnel activity at a contaminated, paved bioaerosol sampling site. Analysis of air samples indicated reaerosolization of spore-containing particles upon disturbance of a contaminated site by a field technician, and analysis of swatches taken from the technician’s clothing indicated substantial transfer of spores. These results provide insight into sources of cross-contamination and potential steps to mitigate consequences of infectious contaminant transfer, and also demonstrate potential exposure hazards for technicians servicing fielded bioaerosol collectors.

This study investigated the effect of high flow conditions on aerosol penetration and the relationship between penetration at constant and cyclic flow conditions. National Institute for Occupational Safety and Health (NIOSH)-approved N95 and P100 filtering facepiece respirators and cartridges were challenged with inert solid and oil aerosols. A combination of monodisperse aerosol and size-specific aerosol measurement equipment allowed count-based penetration measurement of particles with nominal diameters ranging from 0.02 to 2.9 microm. Three constant flow conditions (85, 270, and 360 L/min) were selected to match the minute, inhalation mean, and inhalation peak flows of the four cyclic flow conditions (40, 85, 115, and 135 L/min) tested. As expected, penetration was found to increase under increased constant and cyclic flow conditions. The most penetrating particle size (MPPS) generally ranged from 0.05 to 0.2 microm for P100 filters and was approximately 0.05 microm for N95 filters. Although penetration increased at the high flow conditions, the MPPS was relatively unaffected by flow. Of the constant flows tested, the flows equivalent to cyclic inhalation mean and peak flows best approximated the penetration measurements of the corresponding cyclic flows.

A technology survey was conducted to identify enhancement technologies that offer the most promise for significant advancements in chemical, biological, radiological, and nuclear individual respiratory protection. The focus was on two enhancement areas: protection and physiology. Novel sealing concepts based on responsive materials were sought that offer potential for performance enhancement. The search for cooling technologies focused on air-management systems (i.e., miniature fans and blowers) and thermoelectric devices. Finally, non-carbon based filtration systems that offer improved protection capabilities were sought.