Getting it right in the pandemic

In a research paper that warrants close scrutiny by hospital administrators everywhere, Min Liu and colleagues find that none of 420 healthcare workers deployed to a hospital in Wuhan were infected with the virus, despite caring for severely ill patients and performing aerosol generating procedures over 6-8 weeks.3 The workers wore surgical masks and N95 respirators as well as protective suits and gowns, goggles, gloves, and face shields. The US and the UK missed the just right "Goldilocks zone” of hospital capacity by building temporary hospitals that remained mostly empty.6 How did this happen? "Bad modelling based on insufficient data,” says one expert. Missing the Goldilocks zone of hospital capacity during covid-19.

A life-saving collaborative network: repairing ventilators in Brazil

PurposeThis paper aims to investigate the formation of an inter-organizational collaboration network that made it possible to repair 2,516 mechanical respirators that were inoperative in Brazil during the first wave of the COVID-19 pandemic.Design/methodology/approachA qualitative approach was used in a single case study with semi-structured interviews. The interviewee selection process was non-probabilistic through snowball sampling.FindingsThe results suggest that society, through different social groups with their different roles, can organize itself quickly through the formation of collaborative networks, and this organizational configuration can be an alternative for facing crises where actions isolated would be insufficient or slow to urgently address complex situations.Practical implicationsThis paper aims to (1) demonstrate that society, through different social groups with their different roles, can organize itself quickly through the formation of collaborative networks;(2) favor the understanding and dynamics of the formation of a network;and (3) contribute to a possible replication of this initiative in future contexts.Originality/valueThe case portrays an unprecedented formation of a collaboration network involving more than 144 organizations that mobilized quickly in a complex context of a pandemic and that generated remarkable results through the reintroduction of equipment that were responsible for the preservation of thousands of lives during the year from 2020.

Life Cycle Assessment of Nanofibrous Air Filtering Materials and Respirators

The current spread of COVID-19 pandemics resulted in a surge of a need of respiratory protection devices, including medical facemasks and facepiece respirators. Large amounts of products based on nonwoven filtration material from non-renewable petroleum based plastics (polyethylene) has raised global concerns about excessive environmental impacts of these products. Unfortunately, the replacement of polypropylene nonwoven microfibre based single use masks by the multiple use products did not appear as an effective strategy due to a lower filtration performance, although potentially lower environmental impacts. Nanofibre based filtration devices introduce themselves as potentially more environmentally friendly ones due to a lower overall usage of raw polymer compared to microfibrous ones. We present the LCA modelling of environmental impacts of respiratory protective devices with nanofibrous filter materials and compare those against traditional micro fibrous materials (FFP1 and FFP2 respirator) and medical facemask. Generally, due to a lower mass of nanofibre, these products emerge as a better environmental option, providing similar protection level. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.

N95 masks: skin changes in health professionals in northern Brazil / Máscaras N95: alterações de pele em profissionais de saúde do norte brasileiro / Mascarillas N95: alteraciones en la piel de profesionales de salud en el norte de Brasil

Resumo Objetivo Identificar os fatores associados ao uso de máscara N95 relacionados a alterações de pele entre profissionais de saúde do Norte do Brasil durante a pandemia de COVID-19. Métodos Estudo multicêntrico realizado na região Norte do Brasil no período de outubro a dezembro de 2020, com 1.684 profissionais de saúde que atuaram na assistência à saúde durante a pandemia da COVID-19. Os participantes foram convidados via mídias sociais e as informações coletadas eletronicamente foram armazenadas na plataforma Survey Monkey. Foi usada estatística descritiva para caracterização da amostra, testes de associação (Qui-quadrado), com nível de significância estatística em p < 0,05. Os fatores associados ao uso de máscara N95 relacionados a alterações de pele foram determinados por Regressão Logística Binária, nível de significância de 5% (α = 0,05). Resultados Profissionais de saúde do sexo masculino apresentaram 1,708 mais chances de ter alterações de pele. Outros fatores como, o período de troca de máscara N95, ter atuado em hospital de campanha para COVID-19, terapia intensiva, urgência e emergência e ter recebido alguma capacitação ou curso sobre o COVID-19 foram considerados protetores ao desenvolvimento de alterações de pele, enquanto os principais motivos de troca de máscara N95 foram a umidade, perda de vedação, contaminação, danificação (rasgo). Conclusão Concluiu-se que profissionais de saúde do sexo masculino apresentaram mais chances de ter alterações de pele relacionadas ao uso de máscaras N95. Destacaram-se os fatores protetores e torna-se relevante a realização de estudos de intervenção a fim explorar medidas para prevenção destes tipos de lesões.

Resumen Objetivo Identificar los factores asociados al uso de la mascarilla N95 relacionados con las alteraciones en la piel entre profesionales de salud del norte de Brasil durante la pandemia de COVID-19. Métodos Estudio multicéntrico realizado en la región Norte de Brasil, en el período de octubre a diciembre de 2020, con 1.684 profesionales de salud que actuaron en la asistencia a la salud durante la pandemia de COVID-19. Se convocó a los participantes a través de las redes sociales y la información recopilada electrónicamente fue guardada en la plataforma Survey Monkey. Se utilizó la estadística descriptiva para la caracterización de la muestra, pruebas de asociación (Ji-cuadrado), con un nivel de significación estadística de p < 0,05. Los factores asociados al uso de la mascarilla N95 relacionados con alteraciones en la piel fueron determinados por regresión logística binaria, nivel de significación del 5 % (α = 0,05). Resultados Profesionales de salud de sexo masculino tuvieron 1,708 más posibilidades de presentar alteraciones en la piel. Otros factores como el intervalo de tiempo entre los cambios de mascarillas N95, haber trabajado en hospitales de campaña para COVID-19, cuidados intensivos, urgencias y emergencias y haber realizado alguna capacitación o curso sobre COVID-19 fueron considerados protectores del surgimiento de alteraciones en la piel, mientras que los principales motivos para el cambio de la mascarilla N95 fueron la humedad, la pérdida del sellado, la contaminación y daños (rotura). Conclusión Se concluye que los profesionales de la salud de sexo masculino presentaron más probabilidades de tener alteraciones en la piel relacionadas con el uso de mascarillas N95. Se destacaron los factores protectores y resulta importante la realización de estudios experimentales con la finalidad de explorar medidas para la prevención de este tipo de lesiones.

Abstract Objective To identify the factors associated with N95 mask use related to skin changes among health professionals in northern Brazil during the COVID-19 pandemic. Methods This is a multicenter study carried out in northern Brazil, from October to December 2020, with 1,684 health professionals who worked in health care during the COVID-19 pandemic. Participants were invited via social media and the information collected electronically was stored on the Survey Monkey platform. Descriptive statistics were used to characterize the sample, association tests (chi-square), with statistical significance level at p < 0.05. Factors associated with N95 mask ruse elated to skin changes were determined by Binary Logistic Regression, significance level of 5% (α = 0.05). Results Male health professionals were 1.708 more likely to have skin changes. Other factors such as the N95 mask change period, having worked in a COVID-19 field hospital, intensive care, urgency and emergency and having received some training or course on COVID-19 were considered protective against the development of skin changes, while the main reasons for changing the N95 mask were humidity, loss of seal, contamination, damage (tear). Conclusion We concluded that male health professionals were more likely to have skin changes related to N95 mask use. The protective factors were highlighted and it is relevant to carry out intervention studies in order to explore measures to prevent these types of injuries.

Required Personal Protective Equipment for Prehospital Healthcare Provider in COVID-19 Pandemic: A Systematic Review

Aims. Coronavirus Disease 2019 (COVID-19) is a highly contagious disease, and a variety of personal protective equipment (PPE) has been recommended as preventive measures for prehospital emergency personnel, which has led to considerable challenges and a great confusion for the personnel. This review aims to identify different types of PPE required in the care of COVID-19 patients in prehospital emergency system.Material and methods. This study was carried out by searching through databases including: Pubmed, Proqust, Google Scholar, and Cinahl. All articles that recommended different types of PPE against COVID-19 and infectious diseases for prehospital emergency personnel were collected in a table.Results. After carrying out the initial search in the databases, 1,009 studies were obtained and then 16 articles were selected. The findings seem to suggest using equipment including: gloves, face shields (shield/goggles), protective clothes (medical jumpsuit/scrubs), surgical masks, N-95 masks, powered air purifying respirators (PAPR), hair covers, shoe covers and washing up the hands by the emergency medical service (EMS) personnel.Discussion. The scrutiny of the relevant studies showed that each of them advised the EMS personnel to use a number of PPE. The present study highlighted the fact that there are other components of the PPE which can be useful to them.Conclusion. This study identified the most appropriate PPE needed for prehospital emergency personnel against COVID-19, and it is believed that planning for adequate access to this equipment and training on how to use them can significantly help to reduce the infection among the personnel.

Acute effects of different facemasks during High Intensity Interval Training in trained women. A randomized crossover pilot study

The aim of the present investigation was to analyze the acute effect of different facemasks on physiological, perceptual and performance parameters in trained young women during a High Intensity Interval Training (HIIT) on cycle ergometer. Fifteen subjects participated in the study. Heart rate variability, muscle oxygen saturation, lactate concentration and comfort parameters were measured under 3 conditions: no facemask, surgical and FFP2 facemask. The use of facemasks had no effect on any variable related to oxygen saturation, heart rate variability and cycling power during the HIIT protocol. Only lactate concentration revealed significantly lower values in the No mask condition compared to FFP2 3 min after HIIT (p =.038). Regarding the overall perception and comfort, participants reported greater discomfort when wearing the FFP2 mask compared to the No mask condition (p<.05). On the contrary, the analysis of heart rate variability, revealed significant differences (p<.001) in the Pre compared to the Post exercise for all conditions. The use of surgical or FFP2 facemask during HIIT training does not affect performance during strenuous exercise while perceived comfort appears to be lower with FFP2 masks in physically trained women.

How effective are face coverings in reducing transmission of COVID-19?

In the COVID–19 pandemic, billions are wearing face masks, in both health care settings and in public. Which type of mask we should wear in what situation, is therefore important. There are three basic types: cotton, surgical, and respirators (e.g., FFP2, N95 and similar). All are essentially air filters worn on the face. Air filtration is relatively well understood, however, we have almost no direct evidence on the relative role played by aerosol particles of differing sizes in disease transmission. But if the virus concentration is assumed independent of aerosol particle size, then most virus will be in particles µm. We develop a model that predicts surgical masks are effective at reducing the risk of airborne transmission because the filtering material most surgical masks use is highly effective at filtering particles with diameters µm. However, surgical masks are significantly less effective than masks of FFP2, N95 and similar standards, mostly due to the poor fit of surgical masks. Earlier work found that of the air bypasses a surgical mask and is not filtered. This highlights the fact that standards for surgical masks do not specify how well the mask should fit, and so are not adequate for protection against COVID-19.Copyright © 2022 American Association for Aerosol Research

Awareness and Pragmatic Use of Respirators among Dental Healthcare Professionals during COVID-19 Pandemic: A Cross-sectional Study

Aim: This cross-sectional study intends to assess dental healthcare professionals' (DHCPs) knowledge and awareness of the proper use and reuse of respirators. Materials and methods: A hospital-based cross-sectional survey was conducted using a self-administered questionnaire adapted from the Centers for Disease Control and Prevention (CDC) guidelines regarding the use of respirators with the primary objective of cognizance regarding fit testing, use, reuse, and reprocessing. A total of 478 dental professionals, including 192 postgraduate (PG) students, 176 interns, and 110 teaching faculty, participated in the survey. Data were analyzed using descriptive statistics. Results: A cumulative assessment revealed that 56.9% of dental professionals signed in to use level III masks and 29.3% for N95/KN95 respirators. Amongst those individuals using respirators, only 2.9% have got fit testing done. 92.1% (n = 440) were clueless about the various fit testing methods. 75.7% of DHCPs chose rotation base reuse of respirators rather than extended use of respirators. Conclusion: Clear evidence of incognizance among dental professionals regarding respirator use may put the health care professional at risk of infection. The incorporation of respirator training in infection prevention and control programs should be a prerequisite for preventing cross-infection. Clinical significance: There is a definite need for regular training and educational programs among DHCPs on various infection control protocols with the incorporation of respirator training and the terms of use of the respirator. © The Author(s).

Physio-metabolic and clinical consequences of wearing face masks-Systematic review with meta-analysis and comprehensive evaluation.

Background: As face masks became mandatory in most countries during the COVID-19 pandemic, adverse effects require substantiated investigation. Methods: A systematic review of 2,168 studies on adverse medical mask effects yielded 54 publications for synthesis and 37 studies for meta-analysis (on n = 8,641, m = 2,482, f = 6,159, age = 34.8 ± 12.5). The median trial duration was only 18 min (IQR = 50) for our comprehensive evaluation of mask induced physio-metabolic and clinical outcomes. Results: We found significant effects in both medical surgical and N95 masks, with a greater impact of the second. These effects included decreased SpO2 (overall Standard Mean Difference, SMD = -0.24, 95% CI = -0.38 to -0.11, p < 0.001) and minute ventilation (SMD = -0.72, 95% CI = -0.99 to -0.46, p < 0.001), simultaneous increased in blood-CO2 (SMD = +0.64, 95% CI = 0.31-0.96, p < 0.001), heart rate (N95: SMD = +0.22, 95% CI = 0.03-0.41, p = 0.02), systolic blood pressure (surgical: SMD = +0.21, 95% CI = 0.03-0.39, p = 0.02), skin temperature (overall SMD = +0.80 95% CI = 0.23-1.38, p = 0.006) and humidity (SMD +2.24, 95% CI = 1.32-3.17, p < 0.001). Effects on exertion (overall SMD = +0.9, surgical = +0.63, N95 = +1.19), discomfort (SMD = +1.16), dyspnoea (SMD = +1.46), heat (SMD = +0.70), and humidity (SMD = +0.9) were significant in n = 373 with a robust relationship to mask wearing (p < 0.006 to p < 0.001). Pooled symptom prevalence (n = 8,128) was significant for: headache (62%, p < 0.001), acne (38%, p < 0.001), skin irritation (36%, p < 0.001), dyspnoea (33%, p < 0.001), heat (26%, p < 0.001), itching (26%, p < 0.001), voice disorder (23%, p < 0.03), and dizziness (5%, p = 0.01). Discussion: Masks interfered with O2-uptake and CO2-release and compromised respiratory compensation. Though evaluated wearing durations are shorter than daily/prolonged use, outcomes independently validate mask-induced exhaustion-syndrome (MIES) and down-stream physio-metabolic disfunctions. MIES can have long-term clinical consequences, especially for vulnerable groups. So far, several mask related symptoms may have been misinterpreted as long COVID-19 symptoms. In any case, the possible MIES contrasts with the WHO definition of health. Conclusion: Face mask side-effects must be assessed (risk-benefit) against the available evidence of their effectiveness against viral transmissions. In the absence of strong empirical evidence of effectiveness, mask wearing should not be mandated let alone enforced by law. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021256694, identifier: PROSPERO 2021 CRD42021256694.

Recycling of Anti-COVID-19 Filtering Facepiece Respirators for Use as Preliminary Water Filters.

Although the United Nations has set sustainable management of water as an important worldwide goal, methods to supply clean water to underdeveloped countries are generally lacking. The ongoing COVID-19 pandemic as increased the worldwide use of filtering facepiece respirators (FFRs), resulting in enormous amounts of plastic waste. The present study tested whether FFRs could be recycled for use as preliminary water filters. Filtering of contaminated water with FFRs significantly reduced its turbidity, as well as concentrations of total organic carbon and major pollutants such as P, K, Mg, and Fe. Most of the filtered samples satisfied the drinking water quality standards of the World Health Organization. The additional use of FFRs decontamination process with hydrogen peroxide or ultraviolet germicidal irradiation, and sterilization with water purification tablets can eliminate disease-causing microorganisms and further reduce turbidity that would make water suitable for drinking. Recycling anti-COVID-19 FFRs for use as preliminary water filters is an effective and sustainable method for solving both drinking water problems and waste due to FFRs. Supplementary Information: The online version contains supplementary material available at 10.1007/s41742-023-00526-w.

Personalized 3D-printed frames to reduce leak from N95 filtering facepiece respirators: a prospective crossover trial in health care workers.

Correctly fitting N95 filtering facepiece respirators (FFRs) have become increasingly important in health care throughout the COVID-19 pandemic. We evaluated the hypothesis that personalized 3-D-printed frames could improve N95 FFRs quantitative fit test pass rates and test scores in health care workers (HCW). HCW were recruited at a tertiary hospital in Adelaide, Australia (ACTRN 12622000388718). A mobile iPhone camera + app was used to produce 3-D scans of volunteers' faces, which were then imported into a software program to produce personalized virtual scaffolds suited to each user's face and their unique anatomical features. These virtual scaffolds were printed on a commercially available 3-D printer, producing plastic (and then silicone-coated, biocompatible) frames that can be fitted inside existing hospital supply N95 FFR. The primary endpoint was improved pass rates on quantitative fit testing - comparing participants wearing an N95 FFR alone (control 1) with participants wearing the frame + N95 FFR (intervention 1). The secondary endpoint was the fit factor (FF) in these groups, and R-COMFI respirator comfort and tolerability survey scores. N = 66 HCW were recruited. The use of intervention 1 increased overall fit test pass rates to 62/66 (93.8%), compared to 27/66 (40.9%) for controls. (OR for pFF pass 20.89 (95%CI: 6.77, 64.48, P < 0.001). Average FF increased, with the use of intervention 1 to 179.0 (95%CI: 164.3,193.7), compared to 85.2 (95%CI: 70.4,100.0) with control 1. Pass rates and FF were improved with intervention 1 compared to control 1 for all stages of the fit-test: bending, talking, side-to-side, and up-down motion. (P < 0.001 all stages). Tolerability and comfort of the frame was evaluated with the validated R-COMFI respirator comfort score, showing improvement with the frame compared to N95 FFR alone (P = 0.006). Personalized 3-D-printed face frames decrease leakage, improve fit testing pass rates and FF, and provide improved comfort compared to the N95 FFR alone. Personalized 3-D-printed face frames represent a rapidly scalable new technology to decrease FFR leakage in HCW and potentially the wider population.

Changes to infection prevention and control measures used by Canadian paramedics in response to COVID-19

IntroductionCanadian Paramedic services modified infection prevention and control (IPAC) practices in response to COVID-19. These changes may affect risk of exposure to infectious disease agents and can be used to inform future IPAC practices. We characterized COVID-19-related IPAC changes in the provinces of Alberta, British Columbia, Manitoba, Ontario, and Saskatchewan.Materials & MethodsQuestionnaire data (January 2021-Feb 2022) from the national COVID-19 Occupational Risks, Seroprevalence and Immunity among Paramedics (CORSIP) project was used to identify which IPAC practices were in place prior to COVID-19, and which were modified in response to COVID-19, including the timing of changes (March-May 2020;June-Aug 2020;Sept-Nov 2020;Nov 2020-present).Results2939 participants were included (146, 1249, 139, 1317, 88 from Alberta, BC, Manitoba, Ontario, and Saskatchewan, respectively), of whom 2674 (91%) reported receiving IPAC training. IPAC measures that were common prior to COVID-19 included: personal protective equipment (PPE) training, patient screening, hand hygiene, N95/P100 respirators, gowns, impermeable suits, and cleaning/disinfection. COVID-related IPAC changes included: screening staff, social distancing, restricting aerosol generating procedures, masking patients, cloth face coverings, surgical masks, face shields, and elastomeric respirators. Changes were reported for all IPAC measures. Most (71%) of these changes were made early in the COVID-19 pandemic (March-May 2020). Differences in proportions across provinces, community practice settings, and professional regulation status were reported (p < .05) for hand hygiene, PPE training, screening of patients, face shields, and various respirator types.ConclusionCanadian paramedic services were quick to modify available IPAC measures. However, these changes were variable across provinces, regulation status, and setting for specific IPAC measures. Inconsistent IPAC measures across jurisdictions may contribute to variable risk of infectious disease exposure. An evidence-informed and nationally coordinated approach may provide more equitable exposure risk mitigation for paramedic workers.

Robust Design Optimization of Powered Air Purifying Respirator System by Iterative Process

The personal protective equipment (PPE) has protected the frontline health workers from getting affected in COVID 19 spread situations to a certain level. Among the PPEs, PAPRs (Powered Air Purifying Respirators) are considered as one of the most efficient equipment for protection purposes. In pandemic spread situations, the PAPR becomes very much essential considering its protection. The PAPR is mainly imported to India. But the cost of PAPR being on the higher side (Rupees (Rs) 100000) becomes unaffordable to many frontline health workers. This paper focuses on the development of a cost-effective PAPR that is affordable to them. This paper projects a detailed step-by-step process of design and development of PAPR, and its evolution in each iteration. The study was conducted with the medical officers from AIMS Hospital and engineers from AMMACHI labs to bring out effective solutions for frontline health workers during a pandemic. © 2022 IEEE.

Risk assessment for aerosol infection by SARS-CoV-2 and protection by respirators and surgical masks

SARS-CoV-2 is dispersed from patients by talking, coughing, and sneezing. The generated microdroplets aerosols can travel up to 8m, stay suspended for long periods, and preserve viral infectivity for median of 2.7h. An unprotected person exposed to this cloud might inhale a considerable amount of infectious viral doses, which will attach to the ACE two receptors at the respiratory system epithelial, resulting in infection. N95 respirators and surgical masks block 95% and 50%-60%, respectively, of inhalable particles and protect the wearer from infection. Surgical masks and N95 without exhalation valve protect both the wearer and the environment from carriers and sick people. The highest risk of infection is in closed and unventilated spaces. Any kind of respiratory protection will mitigate risk of infection, including cloth masks, but none will protect if there is no good seal around the face. Medical staff and laboratory workers will benefit most by wearing NIOSH approved N95 respirators, while adhering to guidelines and instructions for keeping the seal around the face. N95 with exhale valve protects the wearer but not others. Face shields with combination of masks or respirators provide additional protection from infection, by reducing ocular exposure or contamination of masks or hands, as well as by diverting movement of air around the face. © 2023 Elsevier Inc. All rights reserved.

Nosocomial SARS-CoV-2 transmission in multi-bedded hospital cubicles over successive pandemic waves: Lower mortality but wider spread with Omicron despite enhanced infection-prevention measures.

BACKGROUND: Increased transmissibility of severe-acute-respiratory-syndrome-coronavirus-2(SARS-CoV-2) variants, such as the Omicron-variant, presents an infection-control challenge. We contrasted nosocomial transmission amongst hospitalized inpatients across successive pandemic waves attributed to the Delta- and Omicron variants, over a 9-month period in which enhanced-infection-prevention-measures were constantly maintained. METHODS: Enhanced-infection-prevention-measures in-place at a large tertiary hospital included universal N95-usage, routine-rostered-testing (RRT) for all inpatient/healthcare-workers (HCWs), rapid-antigen-testing (RAT) for visitors, and outbreak-investigation coupled with enhanced-surveillance (daily-testing) of exposed patients. The study-period lasted from 21st June 2021-21st March 2022. Chi-square test and multivariate-logistic-regression was utilized to identify factors associated with onward transmission and 28d-mortality amongst inpatient cases of hospital-onset COVID-19. RESULTS: During the Delta-wave, hospital-onset cases formed 2.7% (47/1727) of all COVID-19 cases requiring hospitalisation; in contrast, hospital onset-cases formed a greater proportion (17.7%, 265/1483; odds-ratio, OR = 7.78, 95%CI = 5.65-10.70) during the Omicron-wave, despite universal N95-usage and other enhanced infection-prevention measures that remained unchanged. The odds of 28d-mortality were higher during the Delta-wave compared to the Omicron-wave (27.7%, 13/47, vs. 10.6%, 28/265, adjusted-odds-ratio, aOR = 2.78, 95%CI = 1.02-7.69). Onward-transmission occurred in 21.2% (66/312) of hospital-onset cases; being on enhanced-surveillance (daily-testing) was independently associated with lower odds of onward-transmission (aOR = 0.18, 95%CI = 0.09-0.38). Costs amounted to $USD7141 per-hospital-onset COVID-19 case. CONCLUSION: A surge of hospital-onset COVID-19 cases was encountered during the Omicron-wave, despite continuation of enhanced infection-prevention measures; mortality amongst hospital-onset cases was reduced. The Omicron variant poses an infection-control challenge in contrast to Delta; surveillance is important especially in settings where infrastructural limitations make room-sharing unavoidable, despite the high risk of transmission.

Sensorized Facemask With Moisture-Sensitive RFID Antenna.

Due to the ongoing COVID-19 pandemic, the use of filtering facepiece respirators (FFRs) is increasingly widespread. Since the masks' wetness can reduce its filtering capabilities, the World Health Organization advises to replace the FFRs if they become too damp, but currently, there is no practical way to monitor the masks' wetness. A low-cost moisture sensor placed inside the FFRs could discriminate a slightly damp mask from a wet one, which must be replaced. In this letter, a radio frequency identification (RFID) tag exploiting an auto-tuning microchip for humidity sensing is designed and tested during an ordinary working day and a physical exercise. The tag returns about 1 unit of the digital metric every 3 mg of water generated by breathing and sweating, and it can identify excessively wet masks from commonly used ones.

Qualitative fit test outcomes for N95 filtering facepiece respirators in health care workers.

BACKGROUND: We analyzed the qualitative fit test results of the filtering facepiece respirators (FFRs) used at our institution to determine their performance and utility. METHODS: We retrospectively analyzed 12,582 qualitative fit testing results for several FFR models among 8,809 health care workers (HCWs). RESULTS: The overall failure rate for HCWs was 15.2%. Nearly one-third (2933/8809, 33.3%) had multiple FFRs fit tested. HCW sex was a statistically significant indicator of fit testing failure (χ2 = 29.9, df = 1, P < .001), with women having a 44% higher likelihood (OR, 1.4; 95% CI: 1.27-1.65) than men. There were statistically significant differences in the failure rate across FFRs (Fig 4, F[5, 12475] = 8.4, P < .001). Fluidshield 46867S had a significantly higher failure rate (49%) than the 3M 1860 (P = .012), 3M 1860S (P < .001), 3M 8210 (P < .001), and Safelife (P < .001) FFRs. CONCLUSIONS: There was a large degree of variation in fit testing results for the FFRs tested. Although we were unable to find an FFR that fit more than 95% of the HCWs successfully, we identified poorly functioning FFRs that can help our institution with decision-making and budgeting for acquisition and stocking appropriate FFRs.

Experimental Measurement of the Size of Gaps Required to Compromise Fit of an N95 Respirator.

OBJECTIVES: The effectiveness of filtering facepiece respirators such as N95 respirators is heavily dependent on the fit. However, there have been limited efforts to discover the size of the gaps in the seal required to compromise filtering facepiece respirator performance, with prior studies estimating this size based on in vitro models. In this study, we measure the size of leak necessary to compromise the fit of N95 respirators. METHODS: Two methods were used to create a gap of specific dimensions. A set of 3D-printed resin spacers and hollow steel rods were used to generate gaps in N95 respirators while worn on two participants. Occupational Safety and Health Administration (OSHA) quantitative fit testing methods were used to quantify mask performance with gaps between 0.4 and 2.9mm diameters. RESULTS: Gap size was regressed against fit factor, showing that overall the minimum gap size to compromise N95 performance was between 1.5mm2 and 3mm2. CONCLUSIONS: These findings suggest the fit of a N95 respirator is compromised by gaps that may be difficult to visually detect. The study also adds to the body of evidence supporting the routine use of quantitative fit testing to ensure that masks are well-fitting.

The effect of N95 respirators on vital parameters, PETCO2, among healthcare providers at the pandemic clinics.

BACKGROUND: Wearing face shields and masks, which used to have very limited public use before the COVID-19 outbreak, has been highly recommended by organizations, such as CDC and WHO, during this pandemic period. AIMS: The aim of this prospective study is to scrutinize the dynamic changes in vital parameters, change in end tidal CO2 (PETCO2) levels, the relationship of these changes with taking a break, and the subjective complaints caused by respiratory protection, while healthcare providers are performing their duties with the N95 mask. METHODS: The prospective cohort included 54 healthcare workers (doctors, nurses, paramedics) who worked in the respiratory unit of the emergency department (ED) and performed their duties by wearing valved N95 masks and face shields. The vital parameters and PETCO2 levels were measured at 0-4th-5th and 9th hours of the work-shift. RESULTS: Only the decrease in diastolic BP between 0 and 9 h was statistically significant (p = 0.038). Besides, mean arterial pressure (MAP) values indicated a significant decrease between 0-9 h and 5-9 h (p = 0.024 and p = 0.049, respectively). In terms of the vital parameters of the subjects working with and without breaks, only PETCO2 levels of those working uninterruptedly increased significantly at the 4th hour in comparison to the beginning-of-shift baseline levels (p = 0.003). CONCLUSION: Although the decrease in systolic blood pressure (SBP) and MAP values is assumed to be caused by increased fatigue due to workload and work pace as well as increase in muscle activity, the increase in PETCO2 levels in the ED healthcare staff working with no breaks between 0 and 4 h should be noted in terms of PPE-induced hypoventilation.

Clinical Safety and Performance Evaluation of New Personal Protective Equipment During the COVID-19 Pandemic

As the healthcare response to the COVID-19 pandemic continues, providing enhanced protection to frontline healthcare personnel exposed to aerosolized infectious material is essential. The rapid spread of the COVID-19 virus across the globe in early 2020 generated an overwhelming surge in demand for effective personal protective equipment (PPE), in particular, passive personal respirators (PPR). Global manufacturing of PPR was limited, and research and development of improved respirators were restricted by the availability of accredited laboratories for timely testing at the peak of the pandemic. The authors have described a clinical method of safety and efficacy testing of a new PPR, the TopBioShield, using portable capnography for the measurement of end-tidal pCO2 (ETCO2) and bedside pulse oximetry to measure oxygen saturation (SpO2), respiratory rate (RR), and heart rate (HR) in healthy volunteers to overcome shortages of clinical testing capabilities during the height of the pandemic. Twenty-eight volunteers with a median age of 41 years (range 16–71) representing all 10 subgroups of head/face size were included. Only one participant asked to withdraw due to a feeling of claustrophobia after 30 min. Clinical monitoring while wearing TopBioShield revealed ETCO2, SpO2, respiratory rate, and heart rate measurements were within normal limits in all the subjects throughout the experiment. Bedside clinical monitoring is effective in demonstrating the physiological safety of PPR and is an important alternative to conventional mannequin testing. In this study all measured values over a 90-min experiment period were within normal limits, demonstrating the effectiveness of TopBioShield in preventing CO2 retention. Clinical testing methods must adhere to the highest standards and are essential during times of shortage. © 2023, The Institution of Engineers (India).