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1.
Indoor Air ; 32(8): e13099, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36040271

RESUMO

Particle size removal efficiencies for 0.1-1.0 µm ( PSE 0.1 - 1.0 $$ {PSE}_{0.1-1.0} $$ ) and 0.3-1.0 µm ( PSE 0.3 - 1.0 $$ {PSE}_{0.3-1.0} $$ ) diameter of Minimum Efficiency Reporting Value (MERV) filters, an electrostatic enhanced air filter (EEAF), and their two-stage filtration systems were evaluated. Considering the most penetrating particle size was 0.1-0.4 µm particulate matter (PM), the PSE 0.1 - 1.0 $$ {PSE}_{0.1-1.0} $$ as an evaluation parameter deserves more attention during the COVID-19 pandemic, compared to the PSE 0.3 - 1.0 $$ {PSE}_{0.3-1.0} $$ . The MERV 13 filters were recommended for a single-stage filtration system because of their superior quality factor (QF) compared to MERV 6, MERV 8, MERV 11 filters, and the EEAF. Combined MERV 8 + MERV 11 filters have the highest QF compared to MERV 6 + MERV 11 filters and EEAF + MERV 11 filters; regarding 50% of PSE 0.1 - 1.0 $$ {PSE}_{0.1-1.0} $$ as the filtration requirements of two-stage filtration systems, the MERV 8 + MERV 11 filtration system can achieve this value at 1.0 m/s air velocity, while PSE 0.1 - 1.0 $$ {PSE}_{0.1-1.0} $$ values were lower than 50% at 1.5 m/s and 2.0 m/s. EEAF obtained a better PSE 0.3 - 1.0 $$ {PSE}_{0.3-1.0} $$ in the full-recirculated test rig than in the single-pass mode owing to active ionization effects when EEAF was charged by alternating current.


Assuntos
Filtros de Ar , Poluição do Ar em Ambientes Fechados , COVID-19 , Ar Condicionado , Poluição do Ar em Ambientes Fechados/análise , Filtração , Calefação , Humanos , Pandemias , Respiração , Ventilação
2.
Environ Monit Assess ; 194(9): 638, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35925421

RESUMO

We sought to investigate the impact of air purifiers in the removal of particular matter (PM)10, PM2.5, PM1, and particle number concentration (PNC) in the indoor air of dormitories located at Iran's largest medical university, Tehran University of Medical Sciences. Twelve rooms were selected and randomly assigned to two rooms: sham air purifier system deployed room (SR) and true air purifier system deployed room (TR). All study samples were drawn simultaneously from assigned rooms using portable GRIMM dust monitors for 24 h. The PM monitors of air were positioned in the middle of each room next to the air purifier at the height of the breathing zone (1.5 m in height). The mean PM10, PM2.5, PM1, and PNC removal efficiency in rooms with and without a smoker were measured to be 40.7 vs 83.8%, 31.2 vs 78.4%, 29.9 vs 72.3%, and 44.3 vs 75.6%, respectively. The results showed that smoking is an important influencing factor on the indoor air quality; smoking lowered the removal efficiency of PM10, PM2.5, PM1, and PNC by 43%, 47%, 43%, and 31%, respectively. An air purifier could decline the PM10 and PM2.5 even lower than the WHO 24-h guideline level in non-smoker rooms. This study revealed that using household air purifiers in rooms with smokers and non-smokers significantly reduces the non-carcinogenic risks of exposure to PM10 and PM2.5.


Assuntos
Filtros de Ar , Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Humanos , Irã (Geográfico) , Tamanho da Partícula , Material Particulado/análise , Medição de Risco
3.
Artigo em Inglês | MEDLINE | ID: mdl-36012090

RESUMO

Air purifiers should pay much attention to hospital-associated infections, but the role of a single air purifier is limited. The goal of this study was to evaluate the effectiveness of the combined application of the nonequilibrium positive and negative oxygen ion purifier (PNOI) and the high-efficiency particulate air filter (HEPA) on a complex, polluted environment. Two of the better performing purifiers were selected before the study. The efficacy of their use alone and in combination for purification of cigarette particulate matter (PM), Staphylococcus albicans, and influenza virus were then evaluated under a simulated contaminated ward. PNAI and HEPA alone are deficient. However, when they were combined, they achieved 98.44%, 99.75%, and 100% 30 min purification rates for cigarette PM, S. albus, and influenza virus, respectively. The purification of pollution of various particle sizes and positions was optimized and reduced differentials, and a subset of airborne influenza viruses is inactivated. Furthermore, they were superior to ultraviolet disinfection for microbial purification in air. This work demonstrates the strong purification capability of the combined application of these two air purifiers for complex air pollution, which provides a new idea for infection control in medical institutions.


Assuntos
Filtros de Ar , Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Orthomyxoviridae , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Bactérias , Poeira , Hospitais , Material Particulado/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-35742327

RESUMO

Exposure to fine particulate matter increases the risk of cardiovascular morbidity and mortality. Few studies have tested the beneficial effect of indoor air filtration intervention in patients with cardiovascular disease. The aim of this study is to investigate the effect of air filtration on mitigating cardiovascular health in patients with coronary artery disease. This randomized, double-blind, crossover study is conducted with 38 coronary artery disease patients. The intervention consists of the following three periods: two-week active and sham air filtration interventions, with a two-week washout period. The indoor PM2.5 concentration is continuously monitored during the entire study period. We measure the blood pressure, heart rate variability, baroreflex sensitivity, autonomic function test results, and endothelial function. The two-week active air filtration intervention for two weeks reduces the average indoor concentration of PM2.5 by 33.9%. The indoor PM2.5 concentration is significantly correlated to cross-correlation baroreflex sensitivity. Active air filtration is significantly associated with a decrease in the indicator of oxidative stress represented as 8-hydroxy-2'-deoxyguanosine. This study shows that a short-term air filtration intervention improved baroreflex sensitivity and might reduce oxidative stress in coronary artery disease patients. These findings suggest that the use of an air purifier could mitigate the recurrence of cardiovascular disease events in patients with coronary artery disease.


Assuntos
Filtros de Ar , Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Doenças Cardiovasculares , Doença da Artéria Coronariana , 8-Hidroxi-2'-Desoxiguanosina , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Barorreflexo , Biomarcadores , Doenças Cardiovasculares/induzido quimicamente , Doença da Artéria Coronariana/induzido quimicamente , Estudos Cross-Over , Humanos , Estresse Oxidativo , Material Particulado/análise
5.
Nano Lett ; 22(11): 4354-4361, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35611952

RESUMO

Particulate matter damages engines of vehicles when blown into the ventilation system. Conventional engine-intake filter is cellulose microfiber board with an average diameter larger than ten microns, which has low removal efficiency of ultrafine particular matter. In this work, we apply ultrafine polyurethane nanofibers (∼122.8 nm) onto pleated cellulose board using scalable multinozzle electroblow spinning technology, which improves filtration efficiency of particulate matter with a diameter of less than 0.3 µm PM0.3 greatly. The thermoplastic polyurethane 85A nanofiber membranes are transparent, and display superior filtration performance which meets up with the 95% filtration efficiency standard in GB 19083-2010 technical requirements for protective face mask for medical use. The lightweight pleated thermoplastic polyurethane/cellulose composites intercept ∼90% ultrafine PM0.3 under airflow velocity of 32 L min-1 and possess great resistance to shock. These hierarchically designed filters follow a mechanical mechanism and can be used in on-road and off-road cars in the long run.


Assuntos
Filtros de Ar , Celulose , Filtração , Material Particulado , Poliuretanos
6.
Artigo em Inglês | MEDLINE | ID: mdl-35564533

RESUMO

The aim of the present study was to evaluate the efficacy of an air purifier device (professional XXl inn-561 innoliving) with HEPA 14 filter in reducing the number of suspended particles generated during dental procedures as a vector of COVID-19 transmission. The survey was conducted on 80 individuals who underwent Oral Surgery with dental Hygiene Procedures, divided into two groups based on the operational risk classification related to dental procedures: a Test Group (with application of filtering device) and a Control Group (without filtering device). All procedures were monitored throughout the clinical controls, utilising professional tools such as molecular particle counters (Lasair III 350 L 9.50 L/min), bacteriological plates (Tryptic Soy Agar), sound meters for LAFp sound pressure level (SPL) and LCpk instantaneous peak level. The rate of suspended particles, microbiological pollution and noise pollution were calculated. SPSS software was used for statistical analysis method. The results showed the higher efficacy of the TEST Group on pollution abatement, 83% more than the Control fgroup. Additionally, the contamination was reduced by 69-80%. Noise pollution was not noticeable compared to the sounds already present in the clinical environment. The addition of PAC equipment to the already existing safety measures was found to be significantly effective in further microbiological risk reduction.


Assuntos
Filtros de Ar , COVID-19 , Aerossóis , COVID-19/epidemiologia , Odontologia , Humanos , Pandemias/prevenção & controle
7.
ACS Appl Mater Interfaces ; 14(21): 24850-24855, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35585796

RESUMO

The demand for improved indoor air quality, especially during the pandemic of Covid-19, has led to renewed interest in antiviral and antibacterial air-conditioning systems. Here, air filters of vehicles made of nonwoven polyester filter media were sonochemically coated with CuO nanoparticles by a roll-to-roll coating method. The product, aimed at providing commuters with high air quality, showed good stability and mechanical properties and potent activity against Escherichia coli and Staphylococcus aureus bacteria, H1N1 influenza, and two SARS-CoV-2 variants. The filtering properties of a coated filter were tested, and they were similar to those of the uncoated filter. Leaching tests as a function of airflow were conducted, and the main outcome was that the coating was stable and particles were not detached from the coated media. Extension to other air-conditioning systems was straightforward.


Assuntos
Filtros de Ar , COVID-19 , Vírus da Influenza A Subtipo H1N1 , Antibacterianos/química , Antibacterianos/farmacologia , Antivirais/química , Antivirais/farmacologia , Automóveis , Cobre , Escherichia coli , Humanos , SARS-CoV-2
8.
Sci Rep ; 12(1): 8411, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35589800

RESUMO

In recent years, introducing electrospun airfilters to enhance the removal of PM2.5 and PM10-2.5 has received much interest. In this study, a novel poly-(vinyl) alcohol (PVA)/carbon nanoparticle (CNP)/tea leaf extract (TLE), functionalized nanofibrous air filter (FNA) was fabricated using an electrospinning method. Novelty of the unique work in the blending of CNP and TLE, first of its kind, for the preparation of FNA. Polysaccharide crosslinked FNA has a carbon complex with two monosaccharide units to produce the intrinsic properties of the PM2.5 and PM10-2.5 removal efficiency. The FNA had promising traits of UV protection. The prepared FNA was characterized using physicochemical, mechanical, antimicrobial activity, etc., in addition to its PM2.5 and PM10-2.5 removal efficiency. Pore size and distribution study using the capillary flow porometry method has proved the structure of FNA. FNA exhibited excellent low pressure drop (110 Pa), which are promising characteristics for air purification. FNA from PVA: CNP: TLE exhibited high PM2.5 and PM10-2.5 removal efficiencies of 99.25% and 99.29%, respectively. Hence, the study proved.


Assuntos
Filtros de Ar , Nanofibras , Carbono , Filtração , Nanofibras/química , Material Particulado , Álcool de Polivinil/química
9.
Sci Total Environ ; 838(Pt 1): 155884, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35580674

RESUMO

Public health departments such as CDC and California Department of Public Health (CA-DPH) advise HEPA-purifiers to limit transmission of SARS-CoV-2 indoor spaces. CA-DPH recommends air exchanges per hour (ACH) of 4-6 air for rooms with marginal ventilation and 6-12 in classrooms often necessitating multiple HEPA-purifiers per room, unaffordable in under-resourced community settings. Pressure to seek cheap, rapid air filtration resulted in proliferation of lower-cost, Do-It-Yourself (DIY) air purifiers whose performance is not well characterized compared to HEPA-purifiers. Primary metrics are clean air delivery rate (CADR), noise generated (dBA), and affordability ($$). CADR measurement often requires hard-to-replicate laboratory experiments with generated aerosols. We use simplified, low-cost measurement tools of ambient aerosols enabling scalable evaluation of aerosol filtration efficiencies (0.3 to 10 µm), estimated CADR, and noise generation to compare 3 HEPA-purifiers and 9 DIY purifier designs. DIY purifiers consist of one or two box fans coupled to single MERV 13-16 filters (1″-5″ thick) or quad filters in a cube. Accounting for reduced filtration efficiency of MERV 13-16 filters (versus HEPA) at the most penetrating particle size of 0.3 µm, estimated CADR of DIY purifiers using 2″ (67%), 4″ (66%), and 5″ (85%) filters at lowest fan speed was 293 cfm ($35), 322 cfm ($58), and 405 cfm ($120) comparable to best-in-class, low-noise generating HEPA-purifier running at maximum speed with at 282 cfm ($549). Quad filter designs, popularly known Corsi-Rosenthal boxes, achieved gains in estimated CADR below 80% over single filter designs, less than the 100% gain by adding a second DIY purifier. Replacing one of the four filters with a second fan resulted in gains of 125%-150% in estimated CADR. Tested DIY alternatives using lower-efficiency, single filters compare favorably to tested HEPA-purifiers in estimated CADR, noise generated at five to ten times lower cost, enabling cheap, rapid aerosol removal indoors.


Assuntos
Filtros de Ar , Poluição do Ar em Ambientes Fechados , COVID-19 , Aerossóis , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/prevenção & controle , COVID-19/prevenção & controle , Poeira , Humanos , Pandemias/prevenção & controle , SARS-CoV-2
10.
ACS Appl Mater Interfaces ; 14(16): 18989-19001, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35436100

RESUMO

Antibacterial air filtration membranes are essential for personal protection during the pandemic of coronavirus disease 2019 (COVID-19). However, high-efficiency filtration with low pressure drop and effective antibiosis is difficult to achieve. To solve this problem, an innovative electrospinning system with low binding energy and high conductivity was built to enhance the jet splitting, and a fluffy nanofibrous membrane containing numerous ultrafine nanofibers and large quantities of antibacterial agents was achieved, which was fabricated by electrospinning polyamide 6 (PA6), poly(vinyl pyrrolidone) (PVP), chitosan (CS), and curcumin (Cur). The filtration efficiency for 0.3 µm NaCl particles was 99.83%, the pressure drop was 54 Pa, and the quality factor (QF) was up to 0.118 Pa-1. CS and Cur synergistically enhanced the antibacterial performance; the bacteriostatic rates against Escherichia coli and Staphylococcus aureus were 99.5 and 98.9%, respectively. This work will largely promote the application of natural antibacterial agents in the development of high-efficiency, low-resistance air filters for personal protection by manufacturing ultrafine nanofibers with enhanced antibiosis.


Assuntos
Filtros de Ar , COVID-19 , Quitosana , Curcumina , Nanofibras , Antibacterianos/farmacologia , COVID-19/tratamento farmacológico , Quitosana/farmacologia , Curcumina/farmacologia , Escherichia coli , Filtração , Humanos , Nanofibras/química
11.
J Hazard Mater ; 435: 128978, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35472540

RESUMO

It has been frequently emphasized that highly contagious respiratory disease pathogens (such as SARS-CoV-2) are transmitted to the other hosts in the form of micro-sized aerosols (< 5 µm) in the air without physical contacts. Hospital environments such as negative-pressure unit are considered being consistently exposed to pathogens, so it is essential to quickly discharge them through the effective ventilation system. To achieve that, in the present study, we propose the optimized ventilation mechanism and design for the fastest removal of pathogen-laden aerosol using numerical simulations. We quantitatively evaluated the aerosol removal performance of various ventilation configurations (combinations of air exhaust and supply ducts), and found that the key mechanism is to form the coherent (preferentially upward) airflow structure to surround the respiratory flow containing the aerosol cluster. We believe that the present findings will play a critical role in developing the high-efficiency negative-pressure facility irrespective of its size and environments.


Assuntos
Filtros de Ar , COVID-19 , Aerossóis , Humanos , SARS-CoV-2 , Ventilação
12.
Artigo em Inglês | MEDLINE | ID: mdl-35457569

RESUMO

Recently, significant attention has been paid to air quality awareness and its impact on human health, especially in urban agglomerations. Many types of dust samplers for air quality monitoring are used by governmental environmental monitoring agencies. However, these techniques are associated with high costs; as a consequence, biological methods such as active moss biomonitoring are being developed. The main disadvantages of such techniques are the lack of standardization of the preparation procedures and the lack of reliable comparisons of results with data from instrumental analyses. Our study aimed to compare the results obtained from active biomonitoring with the use of three moss species: Pleurozium schreberi, Sphagnum fallax and Dicranum polysetum. Samples were exposed via the moss-bag technique to measure the concentrations of analytes (Mn, Fe, Cu, Zn, Cd, Hg and Pb) which had accumulated among the total suspended particulates (TSP) collected from the filters of a dust collector in the city of Opole (Opole voivodeship, Poland). With regard to the physicochemical and biological traits of the mosses, their assessed lifetime and actual photochemical efficiency (yield) following exposure were meagre, which may have been related to the change of environment and their exposure to pollutants. When comparing the results obtained by the two methods used to monitor air pollution, the biomonitoring method was found to be incompletely consistent with the reference method. Biological monitoring using mosses must be carefully considered depending on the monitoring objectives, the required level of sensitivity and quality of measurement and the type of pollutant.


Assuntos
Filtros de Ar , Poluentes Atmosféricos , Briófitas , Bryopsida , Poluentes Ambientais , Metais Pesados , Poluentes Atmosféricos/análise , Monitoramento Biológico , Poeira/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Humanos , Metais Pesados/análise
13.
J Occup Environ Hyg ; 19(5): 310-317, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35290164

RESUMO

The purpose of this study was to determine if strategic placement of portable air purifiers would improve effectiveness of aerosol reduction in a space as compared to use as a general room air purifier. Two sizes of portable air purifiers were placed in two different positions intended to function similar to either a local exhaust ventilation hood or an air curtain to determine if strategic placement would lead to a reduction of particles in a worker's position at a desk in an office environment. Particle generators were used to introduce particulate into the air and personal aerosol monitors measured particles during each test condition. Results showed that when the medium room portable air purifiers used in this study were set to high, corresponding to 98 CFM, and placed near the breathing zone of each office worker with the unit's filter cover removed, the particle concentration was reduced 35% beyond the reduction that would be expected if the same units were placed on the floor behind the occupant's workstation. Results also indicated that the larger portable air purifier tested, positioned as close as reasonable to each occupant's breathing zone with the largest capture area possible (i.e., removing the unit's filter cover), delivers the best aerosol reduction performance. The authors concluded that as a layer of protection against transmission of airborne infectious organisms for office occupants, installing a portable air purifier, sized and operated similar to the units tested in this study on the desk 12 inches from the breathing zone of the worker, has the potential to reduce airborne particulate to a greater degree than if the same units were placed outside of the breathing zone, in the general cubicle area.


Assuntos
Filtros de Ar , Poluição do Ar em Ambientes Fechados , COVID-19 , Aerossóis , Poluição do Ar em Ambientes Fechados/prevenção & controle , COVID-19/prevenção & controle , Humanos , Emissões de Veículos , Ventilação
14.
Health Phys ; 122(5): 618-624, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35307725

RESUMO

ABSTRACT: High-efficiency particulate air (HEPA) filters are widely employed by nuclear facilities to remove radiological particulate matter from their effluent exhaust streams. The purpose of this study is to evaluate the relationships between the 10-y HEPA filter lifetime deployment and its other performance indicators. This 10-y-long endeavor to collect and analyze data regarding the service life of HEPA filters at the Pacific Northwest National Laboratory began in 2010. A set of HEPA filters was selected, and the filters have been surveyed and analyzed at least annually to verify compliance with permit conditions. The study suggests the frequency of filter replacement should be based on the actual operational requirements, such as fume hood face velocity and/or efficiency test results, instead of on the prescribed filter "age limit" of 10 y from the date of manufacture (e.g., birth date) when operating under dry conditions. The study has now been completed, and over the past decade, all the HEPA filters have been replaced due to either technical issues as listed in this report or the previously recommended filter "age limit" of 10 y as prescribed by the oversight bodies. Experimentally determined failure rates are also determined from the data set and can be used to estimate the chances of HEPA filters surviving 15, 20, or even 30 y.


Assuntos
Filtros de Ar , Poeira , Filtração/métodos , Material Particulado
15.
Adv Colloid Interface Sci ; 303: 102653, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35349924

RESUMO

COVID-19 is caused via the SARS-CoV-2 virus, a lipid-based enveloped virus with spike-like projections. At present, the global epidemic of COVID-19 continues and waves of SARS-CoV-2, the mutant Delta and Omicron variant which are associated with enhanced transmissibility and evasion to vaccine-induced immunity have increased hospitalization and mortality, the biggest challenge we face is whether we will be able to overcome this virus? On the other side, warm seasons and heat have increased the need for proper ventilation systems to trap contaminants containing the virus. Besides, heat and sweating accelerate the growth of microorganisms. For example, medical staff that is in the front line use masks for a long time, and their facial sweat causes microbes to grow on the mask. Nowadays, efficient air filters with anti-viral and antimicrobial properties have received a lot of attention, and are used to make ventilation systems or medical masks. A wide range of materials plays an important role in the production of efficient air filters. For example, metals, metal oxides, or antimicrobial metal species that have anti-viral and antimicrobial properties, including Ag, ZnO, TiO2, CuO, and Cu played a role in this regard. Carbon nanomaterials such as carbon nanotubes, graphene, or derivatives have also shown their role well. In addition, natural materials such as biopolymers such as alginate, and herbal extracts are employed to prepare effective air filters. In this review, we summarized the utilization of diverse materials in the preparation of efficient air filters to apply in the preparation of medical masks and ventilation systems. In the first part, the employing metal and metal oxides is examined, and the second part summarizes the application of carbon materials for the fabrication of air filters. After examination of the performance of natural materials, challenges and progress visions are discussed.


Assuntos
Filtros de Ar , Anti-Infecciosos , COVID-19 , Nanotubos de Carbono , Aerossóis , COVID-19/prevenção & controle , Humanos , Máscaras , Óxidos , SARS-CoV-2
16.
Sci Rep ; 12(1): 2803, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264599

RESUMO

The COVID-19 pandemic has demonstrated the real need for mechanisms to control the spread of airborne respiratory pathogens. Thus, preventing the spread of disease from pathogens has come to the forefront of the public consciousness. This has brought an increasing demand for novel technologies to prioritise clean air. In this study we report on the efficacy of novel biocide treated filters and their antimicrobial activity against bacteria, fungi and viruses. The antimicrobial filters reported here are shown to kill pathogens, such as Candida albicans, Escherichia coli and MRSA in under 15 min and to destroy SARS-CoV-2 viral particles in under 30 s following contact with the filter. Through air flow rate testing, light microscopy and SEM, the filters are shown to maintain their structure and filtration function. Further to this, the filters are shown to be extremely durable and to maintain antimicrobial activity throughout the operational lifetime of the product. Lastly, the filters have been tested in field trials onboard the UK rail network, showing excellent efficacy in reducing the burden of microbial species colonising the air conditioning system.


Assuntos
Filtros de Ar/microbiologia , Anti-Infecciosos/química , Antivirais/química , Filtros de Ar/virologia , Anti-Infecciosos/farmacologia , Antivirais/farmacologia , COVID-19/epidemiologia , COVID-19/virologia , Candida albicans/efeitos dos fármacos , Clorexidina/análogos & derivados , Clorexidina/química , Clorexidina/farmacologia , Escherichia coli/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Fatores de Tempo
17.
Int Orthop ; 46(6): 1233-1240, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35292837

RESUMO

PURPOSE: The rapid spread of coronavirus disease 2019 (COVID-19) has increased the use of personal protective equipment. The purpose of this study was to investigate whether a commercially available sterile surgical helmet system (SSHS) can be considered protective against COVID-19 and therefore safe for use. METHODS: A double-blinded randomized controlled study was performed to investigate the efficacy of the ViVi® SSHS with a high-efficiency particulate air filter called HFD Hood (THI, Total Healthcare Innovation GmbH, Feistritz im Rosental, Austria) to protect against respiratory droplets. Forty recruited participants were divided into two different groups. The SSHS was tested using a validated qualitative test for respirator masks through saccharin or placebo solutions based on random allocation into two cohorts. Saccharin droplets are a validated surrogated marker for any elements of viral size, such as coronaviruses. A positive report of sweet taste after saccharin exposure was suggestive of ViVi® SSHS inefficacy in protection against droplets. RESULTS: One participant out of 21 (4.8%) reported positive for taste within the placebo cohort, while five out of 19 (26.3%) reported positive for taste within the saccharin cohort upon testing. Two out of 21 (9.5%) participants reported positive for taste within the placebo cohort, and two out of 19 (10.5%) reported positive for taste within the saccharin cohort upon retesting. There were no statistically significant differences between the saccharin and placebo groups in either the test or retest measurements (p = 0.085 and p = 1.000, respectively). CONCLUSIONS: This study demonstrates that the ViVi® SSHS equipped with HFD Hood protects against respiratory droplets, increasing protection against several microorganisms, including the virus that causes COVID-19, allowing surgeons to carry out procedures on COVID-positive patients in a more comfortable and safer way.


Assuntos
Filtros de Ar , COVID-19 , COVID-19/prevenção & controle , Dispositivos de Proteção da Cabeça , Humanos , Pandemias/prevenção & controle , SARS-CoV-2 , Sacarina
18.
Small ; 18(14): e2107250, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35166038

RESUMO

Particulate matter (PM) pollution has become a serious environmental concern. Nanofibrous filters are widely reported to remove PM from polluted air. Herein, efficient and lightweight PM air filters are presented using airflow synergistic needleless electrospinning composed of auxiliary fields such as an airflow field and a secondary inductive electric field. Compared to needleless electrospinning with other spinnerets, it significantly improves productivity, fiber diameter, and porosity of fibrous air filters. The instant noodle-like nanofiber structure can also be controlled by adjusting the airflow velocity. These air filters exhibit high (2.5 µm particulate matter) PM2.5 removal efficiency (99.9%) and high (0.3 µm particulate matter) PM0.3 removal efficiency (99.1%), low pressure drop (56 Pa for PM2.5 and 78 Pa for PM0.3 ), and large dust holding capacitance (the maximum value is 168 g m-2 for PM2.5 , while 102 g m-2 for PM0.3 ). Meanwhile, the proposed PM filters are also tested suitable and stable to other polluted air filtrations such as cigarette smoke and sawdust. The large-scale synthesis of such an attractive nanofiber structure presents the great potential of high-performance filtration/separation materials.


Assuntos
Filtros de Ar , Nanofibras , Filtração , Material Particulado , Porosidade
19.
J Hazard Mater ; 431: 128514, 2022 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-35217345

RESUMO

Particulate matter (PM) pollution from industrialization poses a great threat to people's health. Although fiber-based filters are used effectively to capture PM, the traditional filters with large diameter suffer from low filtration efficiency, high pressure drop and low temperature resistance. In this study, multilayer poly arylene sulfide sulfone (M-PASS) composite filter was designed and fabricated via electrospinning technology. The M-PASS composite filter is sandwich-structure. Due to the unique structure and composition, the M-PASS filter exhibited outstanding removal efficiency of 99.97 ± 0.0050%, extremely low air resistance of 44.3 ± 0.7 Pa, excellent quality factor (QF) of 0.19 ± 0.0019 Pa-1, and desirable mechanical strength of 7.0 ± 0.2 MPa. Furthermore, the as-prepared M-PASS filter can remain outstanding filtration performance at 200.0 â„ƒ due to the high thermal stability of PASS and the removal efficiency was still above 95.2 ± 0.4% after long-term filtration test. These results demonstrate that the structure of filter is the important one for air filtration and the M-PASS nanofiber filters have great potential in PM removal, especially under high temperature conditions.


Assuntos
Filtros de Ar , Nanofibras , Filtração , Humanos , Nanofibras/química , Material Particulado , Sulfetos , Sulfonas
20.
Int J Biol Macromol ; 203: 601-609, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35122799

RESUMO

Nanofilters made with high adsorption freeze-dried modified cellulose nanofiber (CNF) aerogel were produced. The modification was made using functional groups containing phthalimide, and then their ability to adsorb particulate matter (PM) was evaluated and compared with the control filter (HEPA). The results showed that the highest adsorption of PM2.5 (99.95%) belonged to the nanofilters made of 1.5% phthalimide-modified CNF aerogel, and the lowest adsorption (76.66%) was related to the control samples. Moreover, based on the results, the nanofilter produced from freeze-dried phthalimide-modified CNF aerogel showed high filtration efficiency as well as excellent resistance to temperature and humidity. This modification enables the filter to operate in different environmental conditions, especially for particles less than 0.1 µm that are mainly responsible for reducing air quality, human health, air visibility, and climate change. In conclusion, we developed an environmentally friendly biodegradable nanofilter capable of high-performance filtration functions and structural stability in different environmental conditions.


Assuntos
Filtros de Ar , Nanofibras , Adsorção , Celulose/química , Humanos , Nanofibras/química , Material Particulado
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