Nejvíce citovaný článek - PubMed ID 33431650
An evidence review of face masks against COVID-19
Proper respiratory tract protection is the key factor to limiting the rate of COVID-19 spread and providing a safe environment for health care workers. Traditional N95 (FFP2) respirators are not easy to regenerate and thus create certain financial and ecological burdens; moreover, their quality may vary significantly. A solution that would overcome these disadvantages is desirable. In this study a commercially available knit polyester fleece fabric was selected as the filter material, and a total of 25 filters of different areas and thicknesses were prepared. Then, the size-resolved filtration efficiency (40-400 nm) and pressure drop were evaluated at a volumetric flow rate of 95 L/min. We showed the excellent synergistic effect of expanding the filtration area and increasing the number of filtering layers on the filtration efficiency; a filter cartridge with 8 layers of knit polyester fabric with a surface area of 900 cm2 and sized 25 × 14 × 8 cm achieved filtration efficiencies of 98% at 95 L/min and 99.5% at 30 L/min. The assembled filter kit consists of a filter cartridge (14 Pa) carried in a small backpack connected to a half mask with a total pressure drop of 84 Pa at 95 L/min. In addition, it is reusable, and the filter material can be regenerated at least ten times by simple methods, such as boiling. We have demonstrated a novel approach for creating high-quality and easy-to-breathe-through respiratory protective equipment that reduces operating costs and is a green solution because it is easy to regenerate.
- MeSH
- aerosoly MeSH
- COVID-19 * prevence a kontrola MeSH
- design vybavení MeSH
- filtrace metody MeSH
- lidé MeSH
- masky MeSH
- polyestery MeSH
- prostředky na ochranu dýchání * MeSH
- testování materiálů metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- aerosoly MeSH
- polyestery MeSH
To function as source control, a fabric mask must be able to filter micro-droplets (≥5 µm) in expiratory secretions and still allow the wearer to breathe normally. This study investigated the effects of fabric structural properties on the filtration efficiency (FE) and air permeability (AP) of a range of textile fabrics, using a new method to measure the filtration of particles in the described conditions. The FE improved significantly when the number of layers increased. The FE of the woven fabrics was generally higher, but double-layer weft knitted fabrics, especially when combined with a third (filter) layer, provided a comparable FE without compromising on breathability. This also confirmed the potential of nonwoven fabrics as filter layers in masks. None of the physical fabric properties studied affected FE significantly more than the others. The variance in results achieved within the sample groups show that the overall performance properties of each textile fabric are a product of its combined physical or structural properties, and assumptions that fabrics which appear to be similar will exhibit the same performance properties cannot be made. The combination of layers of fabric in the design of a mask further contributes to the product performance.
- Klíčová slova
- air permeability, breathability, fabric masks, filtration efficiency, source control,
- Publikační typ
- časopisecké články MeSH
BACKGROUND AND AIMS: SARS-CoV-2 is a worldwide serious health problem. The aim of this study was to demonstrate the number of potentially infectious particles present during endoscopic procedures and find effective tools to eliminate the risks of SARS-CoV-2 infection while performing them. METHODS: An experimental model which focused on aerosol problematics was made in a specialized laboratory. This model simulated conditions present during endoscopic procedures and monitored the formation of potentially infectious fluid particles from the patient's body, which pass through the endoscope and are then released into the environment. For this reason, we designed and tested a prototype of a protective cover for the endoscope's control body to prevent the release and spread of these fluid particles from its working channel. We performed measurements with and without the protective cover of the endoscope's control body. RESULTS: It was found that liquid coming through the working channel of the endoscope with forceps or other instruments inside generates droplets with a diameter in the range of 0.1-1.1 mm and an initial velocity of up to 0.9 m/s. The average number of particles per measurement per whole measured area without a protective cover on the endoscope control body was 51.1; with this protective cover on, the measurement was 0.0, p<0.0001. CONCLUSIONS: Our measurements proved that fluid particles are released from the working channel of an endoscope when forceps are inserted. A special protective cover for the endoscope control body, made out of breathable material (surgical cap) and designed by our team, was found to eliminate this release of potentially infectious fluid particles.
- MeSH
- COVID-19 * prevence a kontrola přenos MeSH
- gastrointestinální endoskopie * MeSH
- lidé MeSH
- ochranné oděvy * MeSH
- přenos infekce z pacienta na zdravotnického pracovníka prevence a kontrola MeSH
- SARS-CoV-2 * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
COVID-19, classified as SARS-CoV-2, is causing an ongoing global pandemic. The pandemic has resulted in the loss of lives and has caused economic hardships. Most of the devices used to protect against the transmission of the novel COVID-19 disease are related to textile structures. Hence, the challenge for textile professionals is to design and develop suitable textile structures with multiple functionalities for capturing viruses, passivating them, and, at the same time, having no adverse effects on humans during the complete period of use. In addition to manufacturing efficient, biocompatible, and cost-effective protective face masks, it is also necessary to inform the public about the benefits and risks of protective face mask materials. The purpose of this article is to address the concerns of efficiency and efficacy of face masks by primarily reviewing the literature of research conducted at the Technical University of Liberec. The main focus is on the presentation of problems related to the specification of aims of face mask applications, mechanisms of capture, durability, and modes of sterilization. The recommendations, instead of conclusions, are addressed to the whole textile society because they should be leading players in the design, creation, and proper treatment of face masks due to their familiarity with the complex behavior of textile structures and targeted changes of structural hierarchy starting from polymeric chains (nano-level) and ending in planar textile structures (millimeter level) due to action by mechanical, physical and chemical fields. This becomes extremely critical to saving hundreds of thousands of lives from COVID-19.
- Klíčová slova
- COVID-19, anti-viral, facemask, nanoparticles, textiles,
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH