Novel Smart N95 Filtering Facepiece Respirator with Real-time Adaptive Fit Functionality and Wireless Humidity Monitoring for Enhanced Wearable Comfort

The widespread emergence of the COVID-19 pandemic has transformed our lifestyle, and facial respirators have become an essential part of daily life. Nevertheless, the current respirators possess several limitations such as poor respirator fit because they are incapable of covering diverse human facial sizes and shapes, potentially diminishing the effect of wearing respirators. In addition, the current facial respirators do not inform the user of the air quality within the smart facepiece respirator in case of continuous long-term use. Here, we demonstrate the novel smart N-95 filtering facepiece respirator that incorporates the humidity sensor and pressure sensory feedback-enabled self-fit adjusting functionality for the effective performance of the facial respirator to prevent the transmission of airborne pathogens. The laser-induced graphene (LIG) constitutes the humidity sensor, and the pressure sensor array based on the dielectric elastomeric sponge monitors the respirator contact on the face of the user, providing the sensory information for a closed-loop feedback mechanism. As a result of the self-fit adjusting mode along with elastomeric lining, the fit factor is increased by 3.20 and 5 times at average and maximum respectively. We expect that the experimental proof-of-concept of this work will offer viable solutions to the current commercial respirators to address the limitations.Comment: 20 pages, 5 figures, 1 table, submitted for possible publicatio

Ann Occup Hyg

This study aims to elucidate variations in head-and-face shape among the Chinese civilian workers. Most respirator manufacturers are using outdated, Western anthropometric data to design respirators for the Chinese workers. Therefore, newly acquired anthropometric data specific to the Chinese population are needed to create more effective personal protective equipment. The three-dimensional (3D) head scans of 350 participants, who were selected from the 3000 participants in the 2006 Chinese Anthropometric Survey, were processed using geometric processing techniques. Each scan was then linked with the others, making statistical shape analysis on a dense set of 3D points possible. Furthermore, this provided for the reduction of scan noise as well as for the patching of holes. Following general scan correspondence and fine tuning, principal component analysis was used to analyze the variability in head-and-face shape of the 3D images. More than 90% of the variability among head-and-face shapes was accounted for with 26 principal components. Future study is recommended so the overall usefulness of the point cloud-based approach for the quantification of variations in facial morphology may be determined.20152017-07-11T00:00:00ZCC999999/Intramural CDC HHS/United States25858431PMC5504517711

Effective Respiratory Protection for Low Resource Areas

ME450 Capstone Design and Manufacturing Experience: Fall 2020Developed respiratory protection for frontline medical workers in low resource areas facing N95 shortages, specifically Ghana. Ghana is unable to manufacture N95 masks, and they are currently being imported. To navigate this issue, our team worked with local stakeholders including the Ghana Society of Biomedical Engineers. Our team designed a solution that effectively filters COVID-19 particles using local materials at an affordable price. The report includes the team's final design solution of a cloth mask with an inserted N95 filter.Caroline Soyars, College of Engineering Global Health Design Initiative, University of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/164435/1/Effective_Respiratory_Protection_for_Low_Resource_Areas.pd

Laminar Flow Face Shield

The scope of this project was to design a personal protective equipment (PPE) that protects the wearer from SARS-CoV-2 without inhibiting communication and was comfortable to wear for long periods of time. SARS-CoV-2, commonly known as COVID-19, is a contagious respiratory virus that spreads through droplets produced when someone who is infected by the virus coughs, sneezes, or talks. These droplets may land on the mouths or noses of nearby people or may be inhaled in the lungs, infecting those who come in contact with the virus. The current guidelines to help slow the spread of COVID-19 are to wear a mask that covers the mouth and nose when around others [1]. However, this causes the wearer\u27s voice to be muffled and be difficult to understand, covers the wearer\u27s facial expressions, inhibits others from picking up on important facial cues, and can become uncomfortable after long periods of wear. An alternative that meets these needs would be a powered air-purifying respirator (PAPR), which is currently sold by several companies in various forms. Many are quite comfortable and allow the user’s face to be seen, but the price is the biggest downfall, most costing over $1,000. Our goal was to design a comfortable, affordable, and effective powered air purifying respirator for Cal Poly professors. We were able to create a respirator that costs only$140, filters out 99.93% of COVID-19 sized particles, and is generally well received in functionality by the general public. This document comprises the results of the critical design process, including background research, specifications, concept development and final design, testing and manufacturing plans, and project timeline

An overview of filtration efficiency through the masks: Mechanisms of the aerosols penetration

The masks have always been mentioned as an effective tool against environmental threats. They are considered as protective equipment to preserve the respiratory system against the non-desirable air droplets and aerosols such as the viral or pollution particles. The aerosols can be pollution existence in the air, or the infectious airborne viruses initiated from the sneezing, coughing of the infected people. The filtration efficiency of the different masks against these aerosols are not the same, as the particles have different sizes, shapes, and properties. Therefore, the challenge is to fabricate the filtration masks with higher efficiency to decrease the penetration percentage at the nastiest conditions. To achieve this concept, knowledge about the mechanisms of the penetration of the aerosols through the masks at different effective environmental conditions is necessary. In this paper, the literature about the different kinds of face masks and respiratory masks, common cases of their application, and the advantages and disadvantages of them in this regard have been reviewed. Moreover, the related mechanisms of the penetration of the aerosols through the masks are discussed. The environmental conditions affecting the penetration as well as the quality of the fabrication are studied. Finally, special attention was given to the numerical simulation related to the different existing mechanisms

Hum Factors

ObjectivesThis article presented four anthropometric theories (univariate, bivariate/probability distribution, multivariate, and shape-based methods) for protective equipment design decisions.BackgroundWhile the significance of anthropometric information for product design is well recognized, designers continue to face challenges in selecting efficient anthropometric data processing methods and translating the acquired information into effective product designs.MethodsFor this study, 100 farm tractor operators, 3,718 respirator users, 951 firefighters, and 816 civilian workers participated in four studies on the design of tractor roll-over protective structures (ROPS), respirator test panels, fire truck cabs, and fall-arrest harnesses, respectively. Their anthropometry and participant-equipment interfaces were evaluated.ResultsStudy 1 showed a need to extend the 90-cm vertical clearance for tractor ROPS in the current industrial standards to 98.3 to 101.3 cm. Study 2 indicated that current respirator test panel would have excluded 10% of the male firefighter population; a systematic adjustment to the boundaries of test panel cells was suggested. Study 3 provided 24 principal component analysis-based firefighter body models to facilitate fire truck cab design. Study 4 developed an improved gender-based fall-arrest harness sizing scheme to supplant the current unisex system.ConclusionsThis article presented four anthropometric approaches and a six-step design paradigm for ROPS, respirator test panel, fire truck cab, and fall-arrest harness applications, which demonstrated anthropometric theories and practices for defining protective equipment fit and sizing schemes.ApplicationsThe study provided a basis for equipment designers, standards writers, and industry manufacturers to advance anthropometric applications for product design and improve product efficacy.CC999999/Intramural CDC HHS/United States2015-09-08T00:00:00Z23516791PMC45623327184vault:263

Additive manufacturing and the COVID-19 challenges: An in-depth study

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapidly achieved global pandemic status. The pandemic created huge demand for relevant medical and personal protective equipment (PPE) and put unprecedented pressure on the healthcare system within a very short span of time. Moreover, the supply chain system faced extreme disruption as a result of the frequent and severe lockdowns across the globe. In such a situation, additive manufacturing (AM) becomes a supplementary manufacturing process to meet the explosive demands and to ease the health disaster worldwide. Providing the extensive design customization, a rapid manufacturing route, eliminating lengthy assembly lines and ensuring low manufacturing lead times, the AM route could plug the immediate supply chain gap, whilst mass production routes restarted again. The AM community joined the fight against COVID-19 by producing components for medical equipment such as ventilators, nasopharyngeal swabs and PPE such as face masks and face shields. The aim of this article is to systematically summarize and to critically analyze all major efforts put forward by the AM industry, academics, researchers, users, and individuals. A step-by-step account is given summarizing all major additively manufactured products that were designed, invented, used, and produced during the pandemic in addition to highlighting some of the potential challenges. Such a review will become a historical document for the future as well as a stimulus for the next generation AM community

Snoring and Its Management (Part 2/2): Preliminary Design and Prototyping of Anti-Snoring Chin Strap Device

The-aim of this-research was to-design and prototype a-chin-strap-device, which can-be-used to-manage largely-untapped local-population of open-mouth-habitual-snorers. Document-analysis was utilized as one of the-study-instruments (including review of: (i) selected-International-patents on the-designs of chin-strap device; (ii) published-research on head-gear, head-products, and the-use of anthropometric-data in their-design; and (iii) prior-art on chin-strap-devices and their-respective-limitations). Target-specifications/ objectives of chin-strap-device were formulated from the-document-analysis, while Pair-wise-Comparison Charts were-used, to-rank the-importance of the-objectives, in the-different-levels.  This-study also used such-basic-tools-as pencil and paper, for sketching, of the-alternative-designs; and a-database, as a-tool for information-storage and retrieval.  Besides, the-study applied fundamental-Engineering-principles of product design, and was-carried-out in-compliance-with both; ISO8559: 1989 (Garment-construction and anthropometric-surveys-body-dimensions), and ISO7250: 1996 (Basic-human-body-measurements for technological-design). The-best-ranked-design (out of the-3 alternatives made) was chosen, via Engineering numerical-weighted-decision-Matrix and ‘Drop and Re-vote’ (D&R) method. 13 head-dimensions, and a-head of a-medium-size, and of normal-shape, for 50th percentile, black-African-male, of over 40 years of age, was selected, as a-design-target. The-values, for these-head-dimensions (one-dimensional measurements), were obtained from IOM and Anthrotech anthropometric-data-tables, for civilian-population. 2D-drawings, of the-selected-alternative, were created via computer-aided-design (CAD) AutoCAD-software. The-fibre, from which the-final-fabric, to-be-made, for a-chin-strap-device, was designed discretely of the-product-design-process, and then was-incorporated, into-the-design, as a-finished input/fabric-structure. This-study also adopted ‘analysis’ method of materials-selection. The-main objectives, of the-intended-device, was used as a-guide, in-materials-selection. Acrylic man-made textile-fibre was selected, via computerized-materials-databases/libraries; and afterwards the-woven-fabric of plain-weave was-chosen as main-material, for the-device. The-fabrication and assembly, of the-prototype, was achieved via stitching-joining-method. Traditional-testing/usability-inspection (by dynamic- verification) was conducted on a-volunteer (open-mouth-snorer); observers reported, that some-snoring reduction was noticeable, in-comparison with the-observations, of the-volunteer, sleeping, without the-device, moreover, the-device stayed-in-position (without sliding-off), during the-five-observation-nights. Overall, the-result of this-preliminary-design is somewhat-optimistic, further-improvement(s) and trials, however, are necessary. The-study, hence, further-recommended to: (1) carry-out a-detailed-design; (2) fabricate the-next/refined-prototype(s); (3) conduct explorative-use-ability-trials, in-collaboration-with the-department of Medical-Engineering, School of Medicine, MU; and (4) analyze the-marketing-aspect of the-design. Keywords: materials-selection, Acrylic, textile, testing