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(PDF) Comparison of Nanoparticle Filtration Performance of NIOSH-approved and CE-Marked Particulate Filtering Facepiece Respirators | Samy Rengasamy - Academia.edu
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"https://www.academia.edu/login?post_login_redirect_url=https%3A%2F%2Fwww.academia.edu%2F9503477%2FComparison_of_Nanoparticle_Filtration_Performance_of_NIOSH_approved_and_CE_Marked_Particulate_Filtering_Facepiece_Respirators%3Fshow_translation%3Dtrue"; window.loswp.previewableAttachments = [{"id":47752817,"identifier":"Attachment_47752817","shouldShowBulkDownload":false}]; window.loswp.shouldDetectTimezone = true; window.loswp.shouldShowBulkDownload = true; window.loswp.showSignupCaptcha = false window.loswp.willEdgeCache = false; window.loswp.work = {"work":{"id":9503477,"created_at":"2014-11-25T22:05:06.752-08:00","from_world_paper_id":128373584,"updated_at":"2024-11-14T21:00:58.992-08:00","_data":{"grobid_abstract":"The National Institute for Occupational Safety and Health (NIOSH) and European Norms (ENs) employ different test protocols for evaluation of air-purifying particulate respirators commonly referred to as filtering facepiece respirators (FFR). The relative performance of the NIOSH-approved and EN-certified 'Conformité Européen' (CE)-marked FFR is not well studied. NIOSH requires a minimum of 95 and 99.97% efficiencies for N95 and P100 FFR, respectively; meanwhile, the EN requires 94 and 99% efficiencies for FFRs, class P2 (FFP2) and class P3 (FFP3), respectively. To better understand the filtration performance of NIOSH-and CE-marked FFRs, initial penetration levels of N95, P100, FFP2 and FFP3 respirators were measured using a series of polydisperse and monodisperse aerosol test methods and compared. Initial penetration levels of polydisperse NaCl aerosols [mass median diameter (MMD) of 238 nm] were measured using a method similar to the NIOSH respirator certification test method. Monodisperse aerosol penetrations were measured using silver particles for 4-30 nm and NaCl particles for 20-400 nm ranges. Two models for each FFR type were selected and five samples from each model were tested against charge neutralized aerosol particles at 85 l min 21 flow rate. Penetrations from the 238 nm MMD polydisperse aerosol test were \u003c1% for N95 and FFP2 models and \u003c0.03% for P100 and FFP3 models. Monodisperse aerosol penetration levels showed that the most penetrating particle size (MPPS) was in the 30-60 nm range for all models of FFRs tested in the study. Percentage penetrations at the MPPS were \u003c4.28, \u003c2.22, \u003c0.009 and \u003c0.164 for the N95, FFP2, P100 and FFP3 respirator models, respectively. The MPPS obtained for all four FFR types suggested particle capturing by electrostatic mechanism. Liquid isopropanol treatment of FFRs shifted the MPPS to 200-300 nm and dramatically increased polydisperse as well as monodisperse aerosol penetrations of all four FFR types indicating that all the four FFR types share filtration characteristics of electret filters. Electrostatic charge removal from all four FFR types also increased penetration levels of 400-1000 nm range particles. Particle penetration data obtained in this study showed that the eight models of NIOSH-approved N95 and P100 and CE-marked FFP2 and FFP3 respirators used in this study provided expected levels of laboratory filtration performance against nanoparticles.","publication_date":"2009,,","publication_name":"Annals of Occupational Hygiene","grobid_abstract_attachment_id":"47752817"},"document_type":"paper","pre_hit_view_count_baseline":null,"quality":"high","language":"en","title":"Comparison of Nanoparticle Filtration Performance of NIOSH-approved and CE-Marked Particulate Filtering Facepiece Respirators","broadcastable":true,"draft":null,"has_indexable_attachment":true,"indexable":true}}["work"]; window.loswp.workCoauthors = [22280917]; window.loswp.locale = "en"; window.loswp.countryCode = "SG"; window.loswp.cwvAbTestBucket = ""; window.loswp.designVariant = "ds_vanilla"; window.loswp.fullPageMobileSutdModalVariant = "control"; window.loswp.useOptimizedScribd4genScript = false; 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ds2-5-body-link" href="https://www.academia.edu/77125700/Filter_quality_of_electret_masks_in_filtering_14_6_594_nm_aerosol_particles_Effects_of_five_decontamination_methods">Filter quality of electret masks in filtering 14.6-594 nm aerosol particles: Effects of five decontamination methods</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="252023374" href="https://independent.academia.edu/CLai12">C. Lai</a><span>, </span><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="61494123" href="https://independent.academia.edu/TzuHsienLin">Tzu-Hsien Lin</a></div><p class="ds-related-work--metadata ds2-5-body-xs">PloS one, 2017</p><p class="ds-related-work--abstract ds2-5-body-sm">This study investigates the effects of five decontamination methods on the filter quality (qf) of three commercially available electret masks-N95, Gauze and Spunlace nonwoven masks. Newly developed evaluation methods, the overall filter quality (qf,o) and the qf ratio were applied to evaluate the effectiveness of decontamination methods for respirators. A scanning mobility particle sizer is utilized to measure the concentration of polydispersed particles with diameter 14.6-594 nm. The penetration of particles and pressure drop (Δp) through the mask are used to determine qf and qf,o. Experimental results reveal that the most penetrating particle size (MPS) for the pre-decontaminated N95, Gauze and Spunlace masks were 118 nm, 461 nm and 279 nm, respectively, and the respective penetration rates were 2.6%, 23.2% and 70.0%. 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However, they are tested for certification using a variety of standardized test methods, creating challenges for the comparison of differently certified products. We have performed systematic experiments to quantify and understand the differences between standardized test methods for N95 respirators (NIOSH TEB-APR-STP-0059 under US 42 CFR 84), medical face masks (ASTM F2299/F2100), and COVID-19-related barrier face coverings (ASTM F3502-21). Our experiments demonstrate the role of face velocity, particle properties (mean size, size variability, electric charge, density, and shape), measurement techniques, and environmental preconditioning. The measured filtration efficiency was most sensitive to changes in face velocity and particle charge. Relative to the NIOSH method, users of the ASTM F2299/F2100 method have commonly used non-neutralized (highly charged) aerosol...</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Systematic experimental comparison of particle filtration efficiency test methods for commercial respirators and face masks (preprint)","attachmentId":77284649,"attachmentType":"pdf","work_url":"https://www.academia.edu/65878396/Systematic_experimental_comparison_of_particle_filtration_efficiency_test_methods_for_commercial_respirators_and_face_masks_preprint_","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/65878396/Systematic_experimental_comparison_of_particle_filtration_efficiency_test_methods_for_commercial_respirators_and_face_masks_preprint_"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="5" data-entity-id="65878358" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/65878358/Systematic_experimental_comparison_of_particle_filtration_efficiency_test_methods_for_commercial_respirators_and_face_masks">Systematic experimental comparison of particle filtration efficiency test methods for commercial respirators and face masks</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="34748228" href="https://ubc.academia.edu/TimothySipkens">Timothy A Sipkens</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Scientific Reports</p><p class="ds-related-work--abstract ds2-5-body-sm">Respirators, medical masks, and barrier face coverings all filter airborne particles using similar physical principles. However, they are tested for certification using a variety of standardized test methods, creating challenges for the comparison of differently certified products. We have performed systematic experiments to quantify and understand the differences between standardized test methods for N95 respirators (NIOSH TEB-APR-STP-0059 under US 42 CFR 84), medical face masks (ASTM F2299/F2100), and COVID-19-related barrier face coverings (ASTM F3502-21). Our experiments demonstrate the role of face velocity, particle properties (mean size, size variability, electric charge, density, and shape), measurement techniques, and environmental preconditioning. The measured filtration efficiency was most sensitive to changes in face velocity and particle charge. Relative to the NIOSH method, users of the ASTM F2299/F2100 method have commonly used non-neutralized (highly charged) aerosol...</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Systematic experimental comparison of particle filtration efficiency test methods for commercial respirators and face masks","attachmentId":77284629,"attachmentType":"pdf","work_url":"https://www.academia.edu/65878358/Systematic_experimental_comparison_of_particle_filtration_efficiency_test_methods_for_commercial_respirators_and_face_masks","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/65878358/Systematic_experimental_comparison_of_particle_filtration_efficiency_test_methods_for_commercial_respirators_and_face_masks"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="6" data-entity-id="71535490" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/71535490/Particle_filtration_efficiency_of_commercial_respirators_and_face_masks_experimental_comparison_of_test_methods">Particle filtration efficiency of commercial respirators and face masks: experimental comparison of test methods</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="34748228" href="https://ubc.academia.edu/TimothySipkens">Timothy A Sipkens</a></div><p class="ds-related-work--metadata ds2-5-body-xs">arXiv: Medical Physics, 2021</p><p class="ds-related-work--abstract ds2-5-body-sm">Respirators, medical masks, and barrier face coverings all filter airborne particles using similar physical principles yet are tested using a variety of variety of standardized test methods. To quantify and understand the effects of differences between the standardized test methods for N95 respirators (NIOSH TEB-APR-STP-0059 under US 42 CFR 84), medical face masks (ASTM F2299/F2100), and COVID-19-related barrier face coverings (ASTM F3502-21). We systematically compared the experimental performance of the NIOSH and ASTM F2299 test methods in terms of face velocity, particle properties (mean size, size variability, electric charge, density, and shape), measurement techniques, and environmental preconditioning. Filtration efficiency is most sensitive to changes in face velocity and particle charge. Relative to the NIOSH method, users of the ASTM F2299 method have normally used non-neutralized (highly charged) aerosols at smaller face velocities, each of which may enhance measured filt...</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Particle filtration efficiency of commercial respirators and face masks: experimental comparison of test methods","attachmentId":80836131,"attachmentType":"pdf","work_url":"https://www.academia.edu/71535490/Particle_filtration_efficiency_of_commercial_respirators_and_face_masks_experimental_comparison_of_test_methods","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/71535490/Particle_filtration_efficiency_of_commercial_respirators_and_face_masks_experimental_comparison_of_test_methods"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="7" data-entity-id="9503481" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/9503481/Evaluation_of_the_Filtration_Performance_of_NIOSH_Approved_N95_Filtering_Facepiece_Respirators_by_Photometric_and_Number_Based_Test_Methods">Evaluation of the Filtration Performance of NIOSH-Approved N95 Filtering Facepiece Respirators by Photometric and Number-Based Test Methods</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="22280917" href="https://independent.academia.edu/SamyRengasamy">Samy Rengasamy</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Journal of Occupational and Environmental Hygiene, 2011</p><p class="ds-related-work--abstract ds2-5-body-sm">N95 particulate filtering facepiece respirators are certified by measuring penetration levels photometrically with a presumed severe case test method using charge neutralized NaCl aerosols at 85 L/min. However, penetration values obtained by photometric methods have not been compared with count-based methods using contemporary respirators composed of electrostatic filter media and challenged with both generated and ambient aerosols. To better understand the effects of key test parameters (e.g., particle charge, detection method), initial penetration levels for five N95 model filtering facepiece respirators were measured using NaCl aerosols with the aerosol challenge and test equipment employed in the NIOSH respirator certification method (photometric) and compared with an ultrafine condensation particle counter method (count based) for the same NaCl aerosols as well as for ambient room air particles. Penetrations using the NIOSH test method were several-fold less than the penetrations obtained by the ultrafine condensation particle counter for NaCl aerosols as well as for room particles indicating that penetration measurement based on particle counting offers a more difficult challenge than the photometric method, which lacks sensitivity for particles < 100 nm. All five N95 models showed the most penetrating particle size around 50 nm for room air particles with or without charge neutralization, and at 200 nm for singly charged NaCl monodisperse particles. Room air with fewer charged particles and an overwhelming number of neutral particles contributed to the most penetrating particle size in the 50 nm range, indicating that the charge state for the majority of test particles determines the MPPS. Data suggest that the NIOSH respirator certification protocol employing the photometric method may not be a more challenging aerosol test method. Filter penetrations can vary among workplaces with different particle size distributions, which suggests the need for the development of new or revised “more challenging” aerosol test methods for NIOSH certification of respirators.</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Evaluation of the Filtration Performance of NIOSH-Approved N95 Filtering Facepiece Respirators by Photometric and Number-Based Test Methods","attachmentId":47752856,"attachmentType":"pdf","work_url":"https://www.academia.edu/9503481/Evaluation_of_the_Filtration_Performance_of_NIOSH_Approved_N95_Filtering_Facepiece_Respirators_by_Photometric_and_Number_Based_Test_Methods","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/9503481/Evaluation_of_the_Filtration_Performance_of_NIOSH_Approved_N95_Filtering_Facepiece_Respirators_by_Photometric_and_Number_Based_Test_Methods"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="8" data-entity-id="44323886" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/44323886/Evaluation_of_filter_media_for_particle_number_surface_area_and_mass_penetrations">Evaluation of filter media for particle number, surface area and mass penetrations</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="175024157" href="https://independent.academia.edu/DavidPui">David Pui</a></div><p class="ds-related-work--metadata ds2-5-body-xs">The Annals of occupational hygiene, 2012</p><p class="ds-related-work--abstract ds2-5-body-sm">The National Institute for Occupational Safety and Health (NIOSH) developed a standard for respirator certification under 42 CFR Part 84, using a TSI 8130 automated filter tester with photometers. A recent study showed that photometric detection methods may not be sensitive for measuring engineered nanoparticles. Present NIOSH standards for penetration measurement are mass-based; however, the threshold limit value/permissible exposure limit for an engineered nanoparticle worker exposure is not yet clear. There is lack of standardized filter test development for engineered nanoparticles, and development of a simple nanoparticle filter test is indicated. To better understand the filter performance against engineered nanoparticles and correlations among different tests, initial penetration levels of one fiberglass and two electret filter media were measured using a series of polydisperse and monodisperse aerosol test methods at two different laboratories (University of Minnesota Partic...</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Evaluation of filter media for particle number, surface area and mass penetrations","attachmentId":64712347,"attachmentType":"pdf","work_url":"https://www.academia.edu/44323886/Evaluation_of_filter_media_for_particle_number_surface_area_and_mass_penetrations","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/44323886/Evaluation_of_filter_media_for_particle_number_surface_area_and_mass_penetrations"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div><div class="ds-related-work--container js-wsj-grid-card" data-collection-position="9" data-entity-id="111174735" data-sort-order="default"><a class="ds-related-work--title js-wsj-grid-card-title ds2-5-body-md ds2-5-body-link" href="https://www.academia.edu/111174735/Filtration_of_nanoparticles_applied_in_general_ventilation">Filtration of nanoparticles applied in general ventilation</a><div class="ds-related-work--metadata"><a class="js-wsj-grid-card-author ds2-5-body-sm ds2-5-body-link" data-author-id="32529430" href="https://concordia.academia.edu/AliBahloul">Ali Bahloul</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Science and Technology for the Built Environment, 2018</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Filtration of nanoparticles applied in general ventilation","attachmentId":108777215,"attachmentType":"pdf","work_url":"https://www.academia.edu/111174735/Filtration_of_nanoparticles_applied_in_general_ventilation","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-wsj-grid-card-view-pdf" href="https://www.academia.edu/111174735/Filtration_of_nanoparticles_applied_in_general_ventilation"><span class="ds2-5-text-link__content">View PDF</span><span class="material-symbols-outlined" style="font-size: 18px" translate="no">chevron_right</span></a></div></div></div></div><div class="ds-sticky-ctas--wrapper js-loswp-sticky-ctas hidden"><div class="ds-sticky-ctas--grid-container"><div class="ds-sticky-ctas--container"><button class="ds2-5-button js-swp-download-button" data-signup-modal="{"location":"continue-reading-button--sticky-ctas","attachmentId":47752817,"attachmentType":"pdf","workUrl":null}">See full PDF</button><button class="ds2-5-button ds2-5-button--secondary js-swp-download-button" data-signup-modal="{"location":"download-pdf-button--sticky-ctas","attachmentId":47752817,"attachmentType":"pdf","workUrl":null}"><span class="material-symbols-outlined" style="font-size: 20px" translate="no">download</span>Download PDF</button></div></div></div><div class="ds-below-fold--grid-container"><div class="ds-work--container js-loswp-embedded-document"><div class="attachment_preview" data-attachment="Attachment_47752817" style="display: none"><div class="js-scribd-document-container"><div class="scribd--document-loading js-scribd-document-loader" style="display: block;"><img alt="Loading..." src="//a.academia-assets.com/images/loaders/paper-load.gif" /><p>Loading Preview</p></div></div><div style="text-align: center;"><div class="scribd--no-preview-alert js-preview-unavailable"><p>Sorry, preview is currently unavailable. 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Oshaughnessy</a></div><p class="ds-related-work--metadata ds2-5-body-xs">Aerosol Science and Technology, 2013</p><div class="ds-related-work--ctas"><button class="ds2-5-text-link ds2-5-text-link--inline js-swp-download-button" data-signup-modal="{"location":"wsj-grid-card-download-pdf-modal","work_title":"Particle Count Statistics Applied to the Penetration of a Filter Challenged with Nanoparticles","attachmentId":99853107,"attachmentType":"pdf","work_url":"https://www.academia.edu/98527659/Particle_Count_Statistics_Applied_to_the_Penetration_of_a_Filter_Challenged_with_Nanoparticles","alternativeTracking":true}"><span class="material-symbols-outlined" style="font-size: 18px" translate="no">download</span><span class="ds2-5-text-link__content">Download free PDF</span></button><a class="ds2-5-text-link ds2-5-text-link--inline js-related-work-grid-card-view-pdf" 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