The Sociability Argument for the Burqa Ban: A Qualified Defence.

Over the past decade, countries such as France, Belgium, Denmark, Austria, Latvia, and Bulgaria have banned face-coverings from public spaces. These bans are popularly known as 'burqa bans' as they seem to have been drafted with the aim of preventing people from wearing burqas and niqabs specifically. The scholarly response to these bans has been overwhelmingly negative, with several lawyers and philosophers arguing that they violate the human right to freedom of religion. While this article shares some of the concerns that have been raised, it argues that banning face-coverings in public is morally justified under certain conditions with the exception of facemasks that are necessary for the containment of infectious diseases, such as COVID-19. The reason for this is that those who publicly cover their face make it very difficult for other members of society to socially interact with them, especially for those who are deaf or hard-of-hearing, which is problematic in an age where many people are chronically lonely or at risk of becoming chronically lonely. As such, this article can be understood as a more elaborate, and arguably more sophisticated, defence of the justification that France offered for its face-covering ban before the European Court of Human Rights, namely that covering one's face undermines the conditions for 'living together'.

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.

Mask communication: The development of the face covering as a semiotic resource through government public health posters in England and Wales.

This paper will explore the multi-modal semiotic properties of a selection of key public health information posters issued by the UK Westminster government on the use of masks and face coverings during the first year of the COVID-19 pandemic. Using multi-modal critical discourse analysis, we show how the posters featuring masks sustained consistent government-led branding, while drawing upon what we describe as "synthetic personalisation" to manage the orientation of the crisis as the pandemic progressed. Through this analysis, the article will highlight the possible contribution of these posters to an environment characterised by political confusion and enabling of a relatively widespread rejection of mask-wearing as a public health responsibility. Examining this within a broader decline in trust in government, we suggest the various attempts to produce a positive message about mask-wearing contributed instead to the appropriation of masks as symbols of individual alignment within a contested political field.

Face masks affect emotion categorisation, age estimation, recognition, and gender classification from faces.

Although putting on a mask over our nose and mouth is a simple but powerful way to protect ourselves and others during a pandemic, face masks may interfere with how we perceive and recognize one another, and hence, may have far-reaching impacts on communication and social interactions. To date, it remains relatively unknown the extent to which wearing a face mask that conceals the bottom part of the face affects the extraction of different facial information. To address this question, we compared young adults' performance between masked and unmasked faces in four different tasks: (1) emotion recognition task, (2) famous face recognition and naming test, (3) age estimation task, and (4) gender classification task. Results revealed that the presence of face mask has a negative impact on famous face recognition and emotion recognition, but to a smaller extent on age estimation and gender classification tasks. More interestingly, we observed a female advantage in the famous face recognition and emotion recognition tasks and a female own-gender bias in gender categorisation and age estimation tasks. Overall, these findings allude to the lack of malleability of the adulthood face recognition and perceptual systems.

Experiences of face mask use during the COVID-19 pandemic: A qualitative study.

The use of face masks and coverings has been a central component of efforts to mitigate the impact of the COVID-19 pandemic and has been legally mandated in some countries. Most academic studies to date, however, have focussed primarily on its effectiveness in reducing SARS-CoV-2 transmission, largely neglecting the social dimensions of mask mandates. In this narrative interview-based study, we consider experiences of face masks, with a particular focus on groups considered to be at a potential disadvantage from compulsory masking. Drawing on 40 telephone, video-call and e-mail interviews, we highlight the impact of inconsistent communication and the notion of mask wearing as an act of altruism on participants' experiences. In particular, we show how intolerance towards individuals who did not wear masks could result in stigma and exclusion, regardless of the legitimacy of their reasons. We suggest that more is needed to mitigate the 'dark side' of discourses of collective effort and altruism at a time of societal stress and fracture, and to account for the needs and interests of groups for whom compulsory masking may result in further marginalisation.

Health sciences students' perception of the communicative impacts of face coverings during the COVID-19 pandemic at a South African University.

BACKGROUND:  The use of face masks and/or shields can pose a challenge during communication. They block facial expressions thus removing visual cues and affect sound transmission making it difficult to hear speech clearly. Given the widespread use of face coverings, it seems reasonable to clarify if communication in typical speakers and listeners has significantly differed. Health science students as future practitioners need to understand challenges that arise from using face coverings. OBJECTIVE:  This study aimed to determine health sciences students' perception of the communicative impacts of face coverings. METHOD:  The study employed a descriptive, self-administered online survey, obtaining information from 96 health science undergraduate students. RESULTS:  All participants changed their manner of speaking in that they spoke louder when wearing masks and focused more on eye contact when someone was wearing masks. These were statistically significant (p = 0.450 and p = 0.035 respectively). Fifty-three percent reported using more listening effort and feeling anxious when communicating. Approximately 33% indicated that it was challenging to read emotions, such as sad or unhappy, when someone wore a mask. Most, 61%, were positive or very positive about wearing masks. The level of difficulty differed depending on the listening environment. It was harder to understand the doctor, nurse, or other healthcare workers when they wore face coverings than when listening to their friends and family, which had little effect, this being statistically significant (p = 0.025). CONCLUSION:  Challenges envisaged in practice included frequent communication breakdowns, inability to connect and build trust between patient and practitioner, and communicating in noisy environments. Coping strategies, future clinical and research implications were proposed, and limitations acknowledged.

A Modified Method for Measuring Pressure Drop in Non-medical Face Masks with Automated Data Acquisition and Analysis.

Background: Non-medical face masks, such as face coverings donned by the general population play an important role in reducing transmission of respiratory pathogens. Pressure drop or breathability of such masks is an important attribute especially with the advent of new standards such as ASTM F3502-21 that have specified pressure drop limits for general use of face coverings. Although several standards are available that discuss pressure drop measurement techniques, the methodologies reported are typically complex or are part of more sophisticated and expensive instruments. Thus, the applicability of such methods is often limited to medical device manufacturers. Objective and Methods: This manuscript adapts from the pressure drop measurements proposed in British Standard EN 14683:2019 and describes a methodology to create a simple 3D printed model of a pressure rig for measuring the breathing resistance across non-medical face masks. The method also enables real time pressure drop data acquisition and analysis of multiple samples or batches using Python and MATLAB scripts. Results: We performed a validation study by comparing the pressure drop obtained for one brand of respirators with our set up and compared it with data obtained by traditional means by CDC. An unpaired two-tailed student t-test (n=3) between the two means implied no statistically significant difference. Conclusion: The method we have developed can be easily implemented at community levels for characterizing the breathability of non-medical grade face masks.

Bacterial Filtration Efficiency of Different Masks

Face coverings, such as surgical masks and respirators, have an important role in preventing bacterial and viral transmission, especially during a global pandemic like COVID-19. Therefore, to secure their availability, new manufacturers and the use of novel materials must be encouraged. However, masks and their materials must first be properly tested for safety and efficiency, as required by the relevant standard, valid in a specific region. All standards prescribe determination of the bacterial filtration efficiency (BFE) of masks. In this study, we report the establishment of a test method for the BFE of face masks in accordance with European standard EN 14683:2019, by which we tested 52 samples, each composed of 3 to 5 subsamples, of surgical and cloth masks, respirators, filters, and mask materials. Forty-seven out of the 52 samples reached a BFE above 75 %. Of these, 16 samples had a BFE of 75 % to 95 %, 3 had a BFE of 95 % to 98 %, while 28 reached a filtration efficiency above 98 %. Our findings show that all tested samples provided some level of protection, most of which met the requirements for the national or European market.

A Simple Method to Quantify Outward Leakage of Medical Face Masks and Barrier Face Coverings: Implication for the Overall Filtration Efficiency.

Face masking proved essential to reduce transmission of COVID-19 and other respiratory infections in indoor environments, but standards and literature do not provide simple quantitative methods for quantifying air leakage at the face seal. This study reports an original method to quantify outward leakage and how wearing style impacts on leaks and filtration efficiency. The amount of air leakage was evaluated on four medical masks and four barrier face coverings, exploiting a theoretical model and an instrumented dummy head in a range of airflows between 30 and 160 L/min. The fraction of air leaking at the face seal of the medical masks and barrier face coverings ranged from 43% to 95% of exhaled air at 30 L/min and reduced to 10-85% at 160 L/min. Filter breathability was the main driver affecting both leak fraction and total filtration efficiency that varied from 5% to 53% and from 15% to 84% at 30 and 160 L/min, respectively. Minor changes were related to wearing style, supporting indications on the correct mask use. The fraction of air leaking from medical masks and barrier face coverings during exhalation is relevant and varies according to design and wearing style. The use of highly breathable filter materials reduces air leaks and improve total filtration efficiency.

Face masks versus sunglasses: limited effects of time and individual differences in the ability to judge facial identity and social traits.

Some research indicates that face masks impair identification and other judgements such as trustworthiness. However, it is unclear whether those effects have abated over time as individuals adjust to widespread use of masks, or whether performance is related to individual differences in face recognition ability. This study examined the effect of masks and sunglasses on face matching and social judgements (trustworthiness, competence, attractiveness). In Experiment 1, 135 participants across three different time points (June 2020-July 2021) viewed unedited faces and faces with masks, sunglasses, or both. Both masks and sunglasses similarly decreased matching performance. The effect of masks on social judgements varied depending on the judgement and whether the face was depicted with sunglasses. There was no effect of timepoint on any measure, suggesting that the effects of masks have not diminished. In Experiment 2, 12 individuals with developmental prosopagnosia (DP) and 10 super-recognisers (SRs) completed the same tasks. The effect of masks on identity matching was reduced in SRs, whereas the effects of masks and sunglasses for the DP group did not differ from controls. These findings indicate that face masks significantly affect face perception, depending on the availability of other facial information, and are not modified by exposure.

[Use of masks by children to prevent infection with SARS-CoV-2]. / Verwendung von Masken bei Kindern zur Verhinderung der Infektion mit SARS-CoV-2: Stellungnahme der Deutschen Gesellschaft für Pädiatrische Infektiologie (DGPI), des Berufsverbandes der Kinder- und Jugendärzte (bvkj e. V.), der Deutschen Gesellschaft für Kinder- und Jugendmedizin (DGKJ), der Gesellschaft für Pädiatrische Pneumologie (GPP), der Deutschen Gesellschaft für Sozialpädiatrie und Jugendmedizin (DGSPJ), der Süddeutschen Gesellschaft für Kinder- und Jugendmedizin (SGKJ) und der Deutschen Gesellschaft für Kinder- und Jugendpsychiatrie, Psychosomatik und Psychotherapie (DGKJP).

After initial reluctance masks have emerged as an important means of restricting the spread of SARS-CoV­2, the new coronavirus causing COVID-19. Other simple measures are keeping a distance of at least 1 ½â€¯m from other persons and observing hygiene recommendations, including washing or even disinfecting the hands, coughing into the crook of the arm and remaining at home when sick. Combining the initial letters of the German words for the three measures (Abstand-Hygiene-Alltagsmaske, distance-hygiene-face mask) the acronym AHA was formed, a colloquial German word meaning that the speaker understood the information presented. This acronym was later extended by the letter "L", initial letter of "Lüften" meaning air ventilation for indoor rooms and arriving at AHA­L, recommended by the federal German Health Institute the Robert Koch Institute. In fact, masks including surgical masks and face coverings can form an effective barrier against the spread of the virus: protecting other people from droplets expelled from the throat of the speaker wearing a mask and even in part protecting the wearer from inhaling droplets emanating from other peoples' throats. Studies to find out if wearing masks might impose risks did not find essential problems: alterations of respiratory parameters due to an increased airway resistance remained within normal limits in healthy adults and even in asthmatics whose disease was well controlled; however, many adults expressed their unease with masks describing them as cumbersome and inconvenient. Emotional resistance against masks made it increasingly more difficult for them to use a mask. Efficient application of masks requires, in addition to a logical explanation of its effect, the evocation of empathy for vulnerable people who can be protected from catching a possibly deadly disease. In children there are very few data on adverse effects of wearing a mask although there is ample experience in children with serious diseases compromising defense against infectious agents acquired via respiratory mucus membranes; however, when using masks appropriately in children relevant adverse effects have not been reported and are not to be expected. Masks should only be used in children when they are healthy and awake and can remove the masks themselves anytime they like. Children 10 years or older can use masks efficiently when they have been informed beforehand appropriate to their age. Under these conditions they can also be obliged to wear masks in certain situations, for example while walking through the school building to their desk in class. To limit the period of wearing a mask normally they will be allowed to remove the mask when sitting in class and keeping their distance. Children in primary schools may use masks, but they should not be obliged to wear them and children in kindergartens should not use masks. This exemption of younger children does not expose school and kindergarten teachers to additional risks since the infectivity with SARS-CoV­2 is age-dependent and increases with age reaching adult values only after 12 years of age.

Experimental Comparison of CWA 17553:2020 Community Face Coverings to Surgical Masks and Filtering Facepiece Respirators

With the worldwide spread of the COVID-19 virus in early 2020, shortages of surgical masks and filtering facepiece respirator (FFR) masks became a critical problem. European governments recommended that civilians should not use these masks so that the shortages in the hospitals would be minimised. In Europe, civilians were instead advised to wear community face coverings. In June 2020, the European Committee for Standardisation (CEN) published CWA 17553:2020 [1–3] which formalised minimum requirements, methods of testing and use of community face coverings. The CWA 17553 is presently only a recommendation, and not an official standard such as the EN14683 standard for surgical masks or the EN149 standard for filtering facepiece respirators. Because there are different performance requirements for these three different classes of masks, it makes comparing their performance challenging. In this work, we perform particulate filtration efficiency measurement, total inward leakage measurement and breathability measurement on a range of surgical masks, filtering facepiece respirators and community face coverings. This analysis provides a useful comparison between material performance and the effectiveness of a mask’s design which is manufactured from this material. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2021.

Mental imagery interventions to promote face covering use among UK university students and employees during the COVID-19 pandemic: study protocol for a randomized controlled trial.

BACKGROUND: The 2020 COVID-19 pandemic has witnessed wide-ranging efforts to minimize the spread of the virus and to protect those most vulnerable to becoming unwell following viral infection. Core COVID-19 preventive measures include social distancing, regular hand washing, and wearing face coverings in public places. Understanding links between social cognitive factors relating to beliefs/skills is important in the context of the COVID-19 pandemic, as this can suggest which factors might be targeted via behaviour change interventions to promote adherence to COVID-19 preventative behaviours. In this context, mental imagery exercises-self-directed imagining of an anticipated outcome or processes linked to a defined behaviour/activity-offer a well-evidenced, relatively simple behaviour change intervention. In the mental imagery invention reported in this protocol, individuals will be randomly assigned to one of four separate conditions (outcome imagery, process imagery, outcome and process imagery, control). METHODS: The primary objective of this randomized controlled study is to assess the effectiveness of a mental imagery intervention on wearing face coverings, as a defined core COVID-19 preventative behaviour. Participants will consist of UK university students and university employees of any age. Participants will be randomized to complete an 'outcome imagery' or a 'process imagery' exercise, both exercises (i.e. a combined condition) or neither exercise (i.e. a control condition). A total of 260 individuals will be recruited into the study. Outcomes for all study condition arms will be assessed at baseline (Time 1), immediately post-intervention (Time 2), and at 1-month follow-up (Time 3). The primary outcome is frequency of wearing face covering, as reported at T2 and T3. Secondary outcomes include intervention effects on face covering attitudes, social norms, perceived behavioural control and barrier self-efficacy at T2 and T3. Putative moderators of intervention effects are conscientiousness, narcissism and 'light triad' personality traits. DISCUSSION: This trial will contribute toward the currently sparse evidence base concerning behaviour change techniques designed to promote COVID-19 preventative behaviours among UK university students and university employees. TRIAL REGISTRATION: ClinicalTrials.gov (U.S. National Library of Medicine) NCT04583449 . Retrospectively registered on 20 October 2020.

Human Research Study of Particulate Propagation Distance From Human Respiratory Function.

BACKGROUND: Airborne viral pathogens like severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be encapsulated and transmitted through liquid droplets/aerosols formed during human respiratory events. METHODS: The number and extent of droplets/aerosols at distances between 1 and 6 ft (0.305-1.829 m) for a participant wearing no face covering, a cotton single-layer cloth face covering, and a 3-layer disposable face covering were measured for defined speech and cough events. The data include planar particle imagery to illuminate emissions by a light-sheet and local aerosol/droplet probes taken with phase Doppler interferometry and an aerodynamic particle sizer. RESULTS: Without face coverings, droplets/aerosols were detected up to a maximum of 1.25 m (4.1ft ±â€…0.22-0.28 ft) during speech and up to 1.37 m (4.5ft ±â€…0.19-0.33 ft) while coughing. The cloth face covering reduced maximum axial distances to 0.61 m (2.0 ft ±â€…0.11-0.15 ft) for speech and to 0.67 m (2.2 ft ±â€…0.02-0.20 ft) while coughing. Using the disposable face covering, safe distance was reduced further to 0.15 m (0.50 ft ±â€…0.01-0.03 ft) measured for both emission scenarios. In addition, the use of face coverings was highly effective in reducing the count of expelled aerosols. CONCLUSIONS: The experimental study indicates that 0.914 m (3 ft) physical distancing with face coverings is equally as effective at reducing aerosol/droplet exposure as 1.829 m (6 ft) with no face covering.

Face Coverings, Aerosol Dispersion and Mitigation of Virus Transmission Risk.

The SARS-CoV-2 virus is primarily transmitted through virus-laden fluid particles ejected from the mouth of infected people. Face covers can mitigate the risk of virus transmission but their outward effectiveness is not fully ascertained. Objective: by using a background oriented schlieren technique, we aim to investigate the air flow ejected by a person while quietly and heavily breathing, while coughing, and with different face covers. Results: we found that all face covers without an outlet valve reduce the front flow through by at least 63% and perhaps as high as 86% if the unfiltered cough jet distance was resolved to the anticipated maximum distance of 2-3 m. However, surgical and handmade masks, and face shields, generate significant leakage jets that may present major hazards. Conclusions: the effectiveness of the masks should mostly be considered based on the generation of secondary jets rather than on the ability to mitigate the front throughflow.

Predictors of mask-wearing during the advent of the COVID-19 pandemic: Evidence from South Africa.

BACKGROUND: In the absence of a vaccine, the global spread of COVID-19 during 2020 has necessitated non-pharmaceutical interventions to curb the rise of cases. PURPOSE: The article uses the health belief model and a novel rapid mobile survey to examine correlates of reported mask-wearing as a non-pharmaceutical intervention in South Africa between May and August 2020. METHODS: Two-way tabulations and multivariable analysis via logistic regression modeling describe correlations between reported mask-wearing and factors of interest among a sample of 7074 adults in a two-period national longitudinal survey, the National Income Dynamics Study-Coronavirus Rapid Mobile Survey (NIDS-CRAM). RESULTS: In line with the health belief model, results showed that self-efficacy, the prevalence of others' mask-wearing in the same district, and affluence were positively associated with reported mask-wearing. Those who reported staying at home were significantly less likely to report wearing a mask. There was little evidence that the expected severity of the disease if contracted, affects these decisions. Hypertension, obesity, or being overweight (measured three years earlier) did not have a significant association with mask-wearing. The prevalence of mask-wearing increased significantly from May to August 2020 as COVID-19 cases increased and lockdown restrictions were eased. Contrary to the health belief model, we found that despite having a higher mortality risk, the elderly had significantly lower odds of mask-wearing. CONCLUSION: In South Africa, the mask-wearing adherence has increased rapidly. It is concerning that the elderly had lower odds of mask-wearing. This should be examined further in future research.

Mask Use Experiences, COVID-19, and Adults with Asthma: A Mixed-Methods Approach.

BACKGROUND: Although masks are recommended for those with asthma in the era of COVID-19, there is limited research exploring the extent of and problems related to mask use in adults with asthma. OBJECTIVE: We sought to describe in adults with asthma: (1) the extent masks are worn and attitudes and beliefs about wearing masks; (2) participant characteristics associated with problems experienced while wearing a mask, and (3) participant experiences and recommendations regarding masks. METHODS: The Mask Use in Adults with Asthma online survey was conducted with 501 adults with asthma (96.6%) primarily from the United States. A Mask Effects Scale (MES) was compiled from items addressing problems experienced wearing a mask with higher total scores indicating more problems. Open-ended questions explored factors considered when choosing a mask, problems experienced while wearing a mask, and recommendations to others with asthma. Survey data were analyzed descriptively and via multiple regression. Themes were generated from open-ended items. RESULTS: Almost all participants (98.4%) indicated wearing a mask in public, and most (67.4%) wore a mask ≤3 hours per day. Poorer asthma control and wearing a mask longer were significantly associated with higher MES scores (P ≤ .001 and .005, respectively). Participant recommendations included "Just wear it," use a comfortable, well-fitting mask, take mask breaks, and carry your inhaler. CONCLUSIONS: Wearing a mask in public was almost uniformly adhered to by participants, despite reporting problematic effects. Implementing recommendations, such as planned mask breaks, can support and enhance the experience of wearing a mask for adults with asthma.

Efficiency of Community Face Coverings and Surgical Masks to Limit the Spread of Aerosol.

In the current pandemic context of COVID-19, people wear different types of masks, particularly in their workplace, to limit the spread of the virus. Depending on their activity and work environment, employees are required to wear community face coverings, cloth masks with a transparent windows, surgical masks, reusable masks, or respirators. The objective of this study was to evaluate the efficiency as source control of these masks, i.e., when worn to protect the environment from the spread of particles emitted by the wearer. An experimental test bench including a dummy head and a breathing simulator associated with a DEHS droplet generator emitting 1 or 3 µm particles in the exhaled stream is used. Source control efficiency is calculated from the total flux of particles emitted in the test section without and with a mask. Seventeen models of masks are tested. Three breathing rate conditions were studied: from rest to heavy breathing, with average rates of 13, 27, and 45 L/min. Source control efficiencies vary from one mask to another. Among community face coverings (seven models) the values ranged from 15.6 to 33.8% for a medium intensity breath. The efficiencies of surgical masks (three models) ranged from 17.4 to 28.3% for the same breathing cycle. The community face coverings and the disposable surgical masks present equivalent values of source control efficiency, respectively, 25.9 and 24.1% at 1 µm and 31.5 and 23.2% at 3 µm. The respirators show higher source control efficiency than the other types of masks (76.7% at 1 µm and 82.5% at 3 µm). The statistical analysis of the data shows no effect of the breathing flow rate and an interaction effect between mask type and particle size. No differences in source control were found for the two particle sizes or the different experimental breathing rates for the respirators and the surgical masks. But the community face coverings and the cloth masks with transparent window present a source control efficiency which increases with the particle size. Varying levels of efficiency were measured with higher source control for respirators than for other types of masks. In the context of a respiratory protection programme, they can provide an effective barrier to the spread of the virus. But these results show also that no mask can stop all the particles emitted by its wearer. Regardless of the type of mask, other barrier measures (ventilation, social distancing, and hygiene) are then necessary.

Disposable face masks and reusable face coverings as non-pharmaceutical interventions (NPIs) to prevent transmission of SARS-CoV-2 variants that cause coronavirus disease (COVID-19): Role of new sustainable NPI design innovations and predictive mathematical modelling.

Best-published evidence supports the combined use of vaccines with non-pharmaceutical interventions (NPIs), to reduce the relative risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes COVID-19; this will enable a safe transition to achieving herd immunity. Albeit complex, the strategic public health goal is to bundle NPIs to keep the basic reproduction number R0 below one. However, validation of these NPIs is conducted using random clinical trials, which is challenging in a swiftly moving pandemic given the need for recruiting large participant cohort over a longitudinal analysis period. This review highlights emerging innovations for potentially improving the design, functionality and improved waste management of disposable face masks such as filtering facepiece (FFPs) respirators, medical masks, and reusable face coverings to help prevent COVID-19. It describes use of different mathematical models under varying scenarios to inform efficacy of single and combined use of NPIs as important counter-measures to break the cycle of COVID-19 infection including new SARS-CoV-2 variants. Demand for face masks during COVID-19 pandemic keeps increasing, especially for FFPs worn by medical workers. Collaborative and well-conducted randomised controlled trials across borders are required to generate robust data to inform common and consistent policies for COVID-19 and future pandemic planning and management; however, current use of systematic reviews of best available evidence can be considered to guide interim policies.

COVID-19: mask efficacy is dependent on both fabric and fit.

Aim: Face masks are an important addition to our arsenal in the fight against COVID-19. The aim of this study is to present a novel method of measuring mask performance which can simultaneously assess both fabric penetration and leakage due to poor fit. Materials & methods: A synthetic aerosol is introduced into the lung of a medical dummy. A conical laser sheet surrounds the face of the dummy where it illuminates the aerosol emitted during a simulated breath. The system is demonstrated with five mask types. Conclusions: The curved laser sheet highlights both penetration through the mask fabric and leakage around the edges of the mask. A large variation in both material penetration and leakage was observed.