Protective masks during the SARS-CoV-2 pandemic: Any relationship with temporomandibular disorders and orofacial pain?

BACKGROUND: Wearing protective face masks has been one of the indispensable measures to prevent droplets and aerosol particles transmission during the SARS-CoV-2 pandemic. OBJECTIVES: This observational cross-sectional survey investigated the different types and modalities of protective mask wearing and the possible association with referred signs of temporomandibular disorders and orofacial pain by respondents. METHODS: An online questionnaire was developed, calibrated and administered anonymously to subjects with an age of ≥18 years. It consisted of different sections: demographics, type and wearing modalities of the protective masks, pain in the preauricular area, noise at the temporomandibular joints and headache. Statistical analysis was performed using statistical software STATA. RESULTS: The questionnaire received 665 replies mainly from participants aged between 18 and 30 years (315 males and 350 females). The healthcare professionals were 37% of participants, 21.2% of them were dentists. The Filtering Facepiece 2 or 3 (FFP2/FFP3) mask was used by 334 subjects (50.3%), and 578 (87%) wore the mask with two elastics behind the ears. Pain while wearing the mask was referred by 400 participants, and 36.8% of them referred pain with a consecutive use of more than 4 h (p = .042). 92.2% of participants did not report any preauricular noise. Headache associated with the FFP2/FFP3 was referred by 57.7% of subjects (p = .033). CONCLUSION: This survey highlighted the increased referred the presence of discomfort in the preauricular area and headache possibly associated with a prolonged use of protective face masks for more than 4 h during the SARS-CoV-2 pandemic.

Improving Safety in Europe-Detecting Counterfeit Certificates from FFP2 Masks: A Text-Mining Approach

At the beginning of the Corona pandemic, there was a surge in demand for medical masks, especially FFP2 masks, which could not be adequately met by existing mask manufacturers. This led to new manufacturers of FFP2 masks entering the market. However, in order for these new suppliers to be allowed to offer these products in conformity with the law, the masks must be tested by an independent body (notified body). This testing usually takes several months and is associated with a number of bureaucratic hurdles and expenses. This led to the fact that untested masks were sold and are still being sold. In order to subsequently identify untested masks, we propose a method that automatically checks a specific document from the testing, namely the type examination certificate. To enable automated evaluation, this paper presents a text-mining approach for verification. It consists of three steps: i) requirements identification of certificates, ii) data extraction and analysis and iii) evaluation of the results using a decision tree classifier. Finally, the algorithm is validated using a case study of several counterfeit FFP2 type examination certificates. The result shows that the text-mining approach is capable of distinguishing fake from real certificates. The ability to analyze certificates in an automated way will completely change the way market surveillance authorities and accredited verification bodies check documents. © 2022 IEEE.

Carbon footprint of FFP2 protective facial masks against SARS-CoV-2 used in the food sector: effect of materials and dry sanitisation

Purpose: International outbreak of the SARS-CoV-2 infection has fostered the Italian government to impose the FFP2 protective facial masks in closed environments, including bar, restaurants and, more in general, in the food sector. Protective facial masks are rocketing, both in mass and in costs, in the food sector imposing efforts in fostering reuse strategies and in the achievement of sustainable development goals. The scope of the present paper is to depict possible strategies in manufacturing and reuse strategies that can reduce the carbon footprint (CF) of such devices. Design/methodology/approach: To implement circular economy strategies in the protective facial masks supply chain, it was considered significant to move towards a study of the environmental impact of such devices, and therefore a CF study has been performed on an FFP2 facial mask used in the food sector. Different materials besides the mostly used polypropylene (PP) (polyethylene (PE), polycarbonate (PC), poly (lactic acid) (PLA), cotton, polyurethane (PUR), polystyrene (PS) and nylon 6,6) and different sanitisation alternatives as reuse strategies (both laboratory and homemade static oven, ultraviolet germicidal irradiation) readily implemented have been modelled to calculate the CF of a single use of an FFP2 mask. Findings: The production of textiles in PP, followed by disposal was the main contributor to CF of the single-use FFP2 mask, followed by packaging and transportations. PP and PE were the least impacting, PC, cotton and Nylon 6-6 of the same weight results the worst. PLA has an impact greater than PP and PE obtained from crude oil, followed by PUR and PS. Static laboratory oven obtained an 80.4% reduction of CF with respect to single use PP-made FFP2 mask, whereas homemade oven obtained a similar 82.2% reduction;UV cabinet is the best option, showing an 89.9% reduction. Research limitations/implications: The key strategies to reduce the environmental impacts of the masks (research for new materials and reuse with sanitisation) should ensure both the retention of filtering capacities and the sanitary sterility of the reused ones. Future developments should include evaluations of textile recycling impacts, using new materials and the evaluation of the life cycle costs of the reused masks. Practical implications: This paper intends to provide to stakeholders (producers, consumers and policy makers) the tools to choose the best option for producing and reuse environmentally friendly protective facial masks to be used in the food sector, by using both different materials and easily implemented reuse strategies. Social implications: The reduction of the CF of protective facial masks in the food sector surely will have relevant positive effects on climate change contributing to reach the goals of reducing CO2 emissions. The food sector may promote sustainable practices and attract a niche piece of clients particularly sensible to such themes. Originality/value: The paper has two major novelties. The first one is the assessment of the CF of a single use of an FFP2 mask made with different materials of the non-woven filtering layers;as the major contribution to the CF of FFP2 masks is related to the non-woven textiles manufacturing, the authors test some other different materials, including PLA. The second is the assessment of the CF of one single use of a sanitised FFP2 mask, using different sanitation technologies as those allowed in bars or restaurants. © 2022, Pasquale Giungato, Bianca Moramarco, Roberto Leonardo Rana and Caterina Tricase.

High efficacy of activated carbon fabric filters and masks developed to prevent the inhalation of microorganisms and particles associated with respiratory tract infections

As a major international public health emergency, COVID-19 has posed many challenges for healthcare professionals who have been heavily exposed to contamination. This article describes the development of a high-filtration capacity mask consisting of filter-element layers interspersed with super-activated carbon fiber fabric, non-woven polypropylene for dental–medical–hospital use and antiviral polyamide with nanostructured SiO2 thin film coating. The study found 98.18% particle filtration efficiency and determined 2.11 mmH2O/cm2 differential pressure, while fluid repellency complied with Brazilian standard NBR ABNT 15052:2004. © The Author(s) 2022.

Does Prolonged FFP2 Mask Use Cause Changes in Nasal Cytology? A Pilot Observational Study on Healthcare Workers.

TheCOVID-19 pandemic has rapidly spread worldwide. Individual prevention approaches include FFP2/N95 mask use. Healthcare (HC) workers wear face masks for a long time during their work shifts and often complain of nasal symptoms. Current data on mask-associated symptoms or upper airway epithelium transformations are limited. Nasal cytology (NC) is a useful, non-invasive diagnostic method to assess cellular alterations. The aim of this study is to compare NC in HC workers before and after the continuous wearing of FFP2 face masks. We conducted a pilot observational study on 10 volunteer HC workers, who continuously used FFP2 masks during the work shift. All subjects underwent NC at the beginning (T0) and at the end of their workshift (T1) and the cytological findings were compared. Moreover, nasal symptoms were collected. Rare inflammatory cells were detected at T0 and, comparing cytological data about T0 and T1, no significant differences were observed. The most reported nasal symptoms were itching (70%) and a dry nose (60%). Difficulty of breathing and nasal blockage were not relevant. These preliminary data seem to suggest that wearing an FFP2 mask does not determine observable alterations in NC in daily work. However, further studies on a larger population for a longer period are needed.

High class filtering facepiece (FFP) are fundamental and effective in protection of emergency health care workers: an observational cohort study in a German community.

BACKGROUND: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a highly contagious airborne virus inducing pandemic coronavirus disease 2019 (COVID-19). This is most relevant for medical staff working under harmful conditions in emergencies often dealing with patients and an undefined SARS-CoV-2 status. We aimed to measure the effect of high-class filtering facepieces (FFP) in emergency medical service (EMS) staff by analyzing seroprevalence and history of positive polymerase chain reaction (PCR) for SARS-CoV-2. METHOD: This observational cohort study included workers in EMS, who were compared with hospital staff (HS) and staff, which was not directly involved in patient care (NPC). All direct patient contacts of EMS workers were protected by FFP2/N95 (filtering face piece protection class 2/non-oil-based particulates filter efficiency 95%) masks, whereas HS was protected by FFP2/N95 exclusively when a patient had a proven or suspected SARS-CoV-2 infection. NPC was not protected by higher FFP. The seroprevalence of SARS-CoV-2 antibodies was analyzed by immunoassay by end of 12/2020 together with the history of a positive PCR. In addition, a self-assessment was performed regarding the quantity of SARS-CoV-2 positive contacts, about flu symptoms and personal belief of previous COVID-19 infections. RESULTS: The period in which contact to SARS-CoV-2 positive patients has been possible was 10 months (March to December 2020)-with 54,681 patient contacts documented for EMS-either emergencies (n = 33,241) or transportation services (n = 21,440). Seven hundred-thirty (n = 730) participants were included into the study (n = EMS: 325, HS: 322 and NPC: 83). The analysis of the survey showed that the exposure to patients with an unknown and consecutive positive SARS-CoV-2 result was significantly higher for EMS when compared to HS (EMS 55% vs. HS 30%, p = 0.01). The incidence of a SARS-CoV-2 infection in our cohort was 1.2% (EMS), 2.2% (HS) and 2.4% (NPC) within the three groups (ns) and lowest in EMS. Furthermore, the belief of previous COVID-19 was significant higher in EMS (19% vs. 10%), CONCLUSION: The consistent use of FFP2/N95 in EMS is able to prevent work-related SARS-CoV-2 infections in emergency situations. The significance of physical airway protection in exposed medical staff is still relevant especially under the aspect of new viral variants and unclear effectiveness of new vaccines.

Clothes Make the Man-What Impact Does the Dress of Interprofessional Teams Have on Patients?

Physicians' attire seems to play an important role in the success of patient treatment. The classic doctor's white coat initiates a strong signal to the patient and can have a determining effect on a successful doctor-patient relationship. In a quantitative online questionnaire study comprising 52 questions, participants were shown four photos of an interprofessional German family medicine team in varying attire. One important study feature relating to the ongoing coronavirus pandemic was that the team was portrayed wearing FFP2 masks in one photo. We measured core values regarding the team's perception in terms of sympathy, competence, trust, choosing the practice as a personal health care provider, and wanting to participate in the team. The questionnaire was posted online between March and May 2021. It was accessed 1435 times and 906 sheets were qualified for statistical analysis. For the first time in this field of research, a practice team's attire was investigated. We found a significant influence of different clothing on the perception of sympathy, competence, trust, elective practice, and team participation. Wearing an FFP2 mask promotes feelings of security and competence. The study shows that in times of fast social changes due to rapid digitalization and an ongoing pandemic, we should present ourselves in different ways as a medical team depending on the patient groups we are targeting and the feelings we want to evoke.

Effects of Wearing FFP2 Masks on SARS-CoV-2 Infection Rates in Classrooms.

In this retrospective cohort study involving 614 secondary school students, the likelihood of becoming infected with SARS-CoV-2 in schools with different focus (sports focus vs. general branch; the only difference in the sports focus school was that PE was allowed at all times without restrictions) and different prevailing restrictions were compared. A significantly higher likelihood of infection with SARS-CoV-2 was found in sports classes during the period with a strict FFP-2 mask requirement compared to general branch classes (for Delta from November 2021 to December 2021, and for Omicron from January 2022 to February 2022). The higher likelihood of infection was observed both during the Delta and the Omicron wave. After the relaxation of the mitigation measures, however, students in general branch classes showed a clear "catch-up" of infections, leading to a higher incidence of infections during this phase. By the end of the observation period (30 April 2022), only a small difference in cumulative SARS-CoV-2 infection rates (p = 0.037, φ = 0.09) was detected between classes with a sports focus and those without a sports focus. The results suggest that SARS-CoV-2 transmission can be reduced in school classes by mandatory FFP-2 mask use. In many cases, however, infection appears to be postponed rather than avoided.

High efficacy of activated carbon fabric filters and masks developed to prevent the inhalation of microorganisms and particles associated with respiratory tract infections

As a major international public health emergency, COVID-19 has posed many challenges for healthcare professionals who have been heavily exposed to contamination. This article describes the development of a high-filtration capacity mask consisting of filter-element layers interspersed with super-activated carbon fiber fabric, non-woven polypropylene for dental-medical-hospital use and antiviral polyamide with nanostructured SiO2 thin film coating. The study found 98.18% particle filtration efficiency and determined 2.11 mmH(2)O/cm(2) differential pressure, while fluid repellency complied with Brazilian standard NBR ABNT 15052:2004.

Verification of two alternative do-it-yourself equipment respirator seal as COVID-19 protection (VADERS-CoV) : a quality assessment pilot study

Background : During the COVID-19 pandemic, healthcare workers were facing shortage in personal protective equipment, especially adequate respirators. Alternative do-it-yourself respirators emerged, without any proof of protection. Objective : Verify seal potential of two alternative respirators compared to a common FFP2 respirator. Design : Quality assessment pilot study. Setting : Tertiary Care Hospital. Participants : Ten anaesthesiology residents. Interventions : Participants performed quantitative face-fit tests (QNFT) with three respirators to evaluate seal. A common FFP2 "duckbill" respirator was used as baseline (control group). Alternatives tested in this study were an anaesthesia face mask and a full-face modified snorkelling mask with a 3D-printed connector, both in conjunction with a breathing system filter. Main outcome : Non-inferior seal performance of the alternatives over FFP2, assessed by calculated QNFT based on measured individual fit factors, as defined by the Occupational Safety and Health Administration. Results :For each respirator a total of 90 individual fit factor measurements were taken. Within the control group, seal failed in 37 (41%) measurements but only in 10 (11%) within the anaesthesia mask group and in 6 (7%) within the snorkelling mask group (P < 0.001 respectively). However, when calculating the final, mean QNFT results, no difference was found between respirators. Successful QNFT were determined for 5 out of 10 participants in the FFP2 group, for 8 in the anaesthesia mask group (P = 0.25) and for 7 in the snorkelling mask group (P = 0.69). Conclusion : Both do-it-yourself respirators successfult) pass QNFT and have the potential to provide non inferior seal compared to a common FFP2 respirator. While anaesthesia masks are easily assembled, snorkelling masks must undergo significant but feasible modifications. Our results suggest that those do-it-yourself respirators seem to be viable alternatives for situations when certified respirators are not available but need further investigation for validation. Trial registration: Clinicaltrials. gov identifier: NCT04375774 Key Points : Question: Can alternative do-it-yourself respirators protect wearers from hazardous aerosols? Findings : Our findings demonstrate that do-it-yourself respirators have the potential to provide non-inferior seal as compared to regular FFP2 personal protective equipment. Meaning : Our real-life situational testing provides evidence that do-it-yourself respirators potentially provide sufficient seal to compete with or even outperform conventional FFP2 respirators and that face-fit testing should be a mandatory safety check in healthcare providers.

Impact of wearing a FFP2 mask on cardiopulmonary fitness in school-aged children

Background and Aim: Wearing face masks to detain the COVID 19 pandemic in schools has become an integral part of fighting the virus. The most effective mask is the FFP2 mask. There is a lot of public concern, especially regarding wearing a face mask at school and especially during school sports. It is therefore important to determine whether wearing a FFP2-mask during physical activ-ity leads to changes measurable in cardiopulmonary exercise test-ing in children. Method(s): Cardiopulmonary exercise testing was performed two times by children aged 8-10 years as an incremental step test on a treadmill with and without a FFP2 within an interval of 2 weeks. A general questionnaire included medical history and sports par-ticipation since childhood. Result(s): We included 10 children (mean age 8.4 +/- 0.7 years, 6 males, 4 females). The mean parameters measured at peak exercise were comparable between both examinations (mean Peak VO2 = 39.3 +/- 3.4 vs 45.6 +/- 13.9 ml/min/kg;mean Peak HR 192/min +/- 9 vs 188/min +/- 12, mean O2pulse 6 +/- 1.4 ml/min vs. 7 +/- 1.8, mean VE 43.2 +/- 12.9 ml/min vs. 41.5 +/- 12.7 ml/min). Neither did the respiratory gases (O2 and CO2) measured 1 min into each step differ significantly (s. figure). This study is cur-rently ongoing. Conclusion(s): Since there were no significant differences with respect to peak parameters as well as with respect to the respiratory param-eters measured during each step, there is no indication to withhold physical activity even at peak capacity from children during a pan-demic which makes wearing face masks mandatory.

Pandemic management requires exposure science.

COVID-19 was first detected in Wuhan, China, on 8.12.2019, and WHO announced it a pandemic on 11.3.2020. No vaccines or medical cures against COVID-19 were available in the first corona year. Instead, different combinations of generic non-pharmaceutical interventions - to slow down the spread of infections via exposure restrictions to 'flatten the curve' so that it would not overburden the health care systems, or to suppress the virus to extinction - were applied with varying levels of strictness, duration and success in the Pacific and North Atlantic regions. Due to an old misconception, almost all public health authorities dismissed the possibility that the virus would be transmitted via air. Opportunities to reduce the inhalation exposure - such as wearing effective FFP2/N95 respirators, improving ventilation and indoor air cleaning - were missed, and instead, hands were washed and surfaces disinfected. The fact that aerosols were acknowledged as the main route of COVID-19 transmission in 2021 opened avenues for more efficient and socially less disruptive exposure and risk reduction policies that are discussed and evaluated here, demonstrating that indoor air and exposure sciences are crucial for successful management of pandemics. To effectively apply environmental and personal exposure mitigation measures, exposure science needs to target the human-to-human exposure pathways of the virus.

Addressing the global challenge of access to supplies during COVID-19: Mask reuse and local production of alcohol-based hand rub

The current COVID-19 pandemic has presented unprecedented challenges for health care facilities worldwide. Global production and shipping routes were disrupted, and health care institutions, even in high resource areas, found themselves lacking the basic supplies for effective infection prevention and control. One major hurdle was the global access to supplies, particularly N95/FFP2 masks and alcohol-based hand rub (ABHR) for performing hand hygiene. © 2021 Elsevier Inc. All rights reserved.

Large-scale decontamination of disposable FFP2 and FFP3 respirators by hydrogen peroxide vapour, Finland, April to June 2020.

BackgroundThe shortage of FFP2 and FFP3 respirators posed a serious threat to the operation of the healthcare system at the onset of the COVID-19 pandemic.AimOur aim was to develop and validate a large-scale facility that uses hydrogen peroxide vapour for the decontamination of used respirators.MethodsA multidisciplinary and multisectoral ad hoc group of experts representing various organisations was assembled to implement the collection and transport of used FFP2 and FFP3 respirators from hospitals covering 86% of the Finnish population. A large-scale decontamination facility using hydrogen peroxide vapour was designed and constructed. Microbiological tests were used to confirm efficacy of hydrogen peroxide vapour decontamination together with a test to assess the effect of decontamination on the filtering efficacy and fit of respirators. Bacterial and fungal growth in stored respirators was determined by standard methods.ResultsLarge-scale hydrogen peroxide vapour decontamination of a range of FFP2 and FFP3 respirator models effectively reduced the recovery of biological indicators: Geobacillus stearothermophilus and Bacillus atrophaeus spores, as well as model virus bacteriophage MS2. The filtering efficacy and facial fit after hydrogen peroxide vapour decontamination were not affected by the process. Microbial growth in the hydrogen peroxide vapour-treated respirators indicated appropriate microbial cleanliness.ConclusionsLarge-scale hydrogen peroxide vapour decontamination was validated. After effective decontamination, no significant changes in the key properties of the respirators were detected. European Union regulations should incorporate a facilitated pathway to allow reuse of appropriately decontaminated respirators in a severe pandemic when unused respirators are not available.

Proof-of-concept of a new FFP2 mask adapted to Otolaryngological practice in pandemic: a prospective study.

OBJECTIVE: The objective of this study was to appreciate the tolerance and convenience of a new FFP2 mask allowed the realization of nasal examination in period of pandemic. METHODS: Fifty-one patients were prospectively recruited from two European hospitals to test the FFP2 mask prototype. The following outcomes were evaluated in patients after the clinical examination: fear about coronavirus disease 2019 (COVID-19) infection; easiness of mask placement; tolerability; reassurance; and overall satisfaction about the use of this kind of mask in a pandemic context. Seven otolaryngologists evaluated the mask acceptance and usefulness in patients through a standardized physician-reported outcome questionnaire. RESULTS: Fifty patients completed the evaluation. There were 25 males and 25 females. The mean age of patients was 41 years. Ninety percent of patients considered that the use of the mask reduced the risk to be infected during the examination. Seventy percent of patients reported high or very high satisfaction and should recommend mask to other patients in pandemic period. The realization of nasal examination was easier with optic compared with flexible trans-nasal examination (p = 0.001), which significantly impacted the satisfaction level of physician (p = 0.001). The physician difficulty to perform the examination significantly impacted the satisfactory of patient (p = 0.033). CONCLUSION: The new bioserenity FFP2 mask allows the realization of the trans-nasal endoscopic examination during a pandemic. The use of this mask requires little training period of physician. The use of this mask prototype is well received by patients who reported better perception of self-protection against the virus.

Evaluation of the effects on SpO2 of N95 mask (FFP2) on dental health care providers: a cross-sectional observational study.

OBJECTIVE: The purpose of this cross-sectional observational study was to evaluate the effects of SpO2 in a sample of dental health care providers who wear a N95 mask or Filtering Face Piece (FFP2) for four consecutive hours, measured by a pulse oximeter before donning the mask and again after four hours of work and to offer some strategies to minimize discomfort and improve communication with their patients while wearing the mask. MATERIALS AND METHODS: A 17-item questionnaire was sent via Google Drive to various practitioners in Italy and the USA. A sample of 162 questionnaires were returned from dentists, orthodontists, dental hygienists and dental assistants who committed to wearing a FFP2 for 4 consecutive hours during a work day and then measuring the oxygen saturation by way of a pulse oximeter before and after the 4 working hours. The final analysis was performer on 147 viable questionnaires returned. The sample was composed of 62 males and 85 females with an average age of 42.9 ± 12.0 years. RESULTS: For the entire sample population, the baseline saturation was 98.6 ± 1.2 and, after four hours of mask wearing, there was a significant decrease in oxygen saturation to 97.0 ± 2.9 (p < 0.01). No statistical differences in SpO2 were found across specialties or across types of procedures performed during the 4 h. Heart rates were not significantly different before and after the 4 h in all categories. The 3 most frequent reported complaints were: fatigue (64%), headache (36%) and external ear pain (31%). The most common additional personal protective equipment (PPE) was a mask shield (78%) and those who wore the mask continuously reported more communication difficulty with patients, compared with those who took the mask off more often, in fact, 64% of the subjects reported that using the mask influenced their communication with their patients. Based on the results of the questionnaire, a list of breathing and vocal folds health strategies was devised and proposed, along with strategies to augment communication with patients. CONCLUSIONS: This study highlights a significant decrease in oxygen saturation after only 4 h of work (except for smokers) while wearing a FFP2, and confirms the widespread symptoms of fatigue, headache and pain behind the ears that dental professionals experience. But it also highlighted how mask wearing impaired communication with patients and wearing additional masks and a facial shield may add to those communications difficulties. This aspect and the need for better communication can lead the operators to remove the mask to improve breathing and communication, thus putting themselves at a risk of infection. Of all the aspects explored in this study, the most interesting was indeed the impact on fatigue and communication and the strategies proposed in this article can easily be implemented to reduce headache and fatigue by improving breathing efficiency and by aiding communication while donning a mask by improving voice quality and by using augmentative communication tools.

Effect of Face Masks on Blood Saturation, Heart Rate, and Well-Being Indicators in Health Care Providers Working in Specialized COVID-19 Center.

This study aims to investigate whether wearing face masks (filtering facepieces, FFP class 2) with personal protective equipment (FPP2/PPE), while working a 12-h shift in a COVID-19 referral center, affects the blood saturation, heart rate (HR), and well-being of health care providers (HCPs). The study included a group of 37 HCPs. To perform continuous recordings of the SpO2 and heart rate (HR) in real time, we used a Nellcor PM10N (Covidien, Mansfield, MA, USA) portable monitoring system. SpO2, HR, and HCP well-being scales were measured during two 3-h shifts, while HCPs worked during a 12-h period. Additionally, each subject completed a questionnaire concerning their well-being. The difference in the SpO2 level between the 1st and 2nd working shifts while wearing an FFP2/PPE was small, with a median decrease in SpO2 of -1%. The scales of the well-being indicators increased within the shift. They were mainly fatigue and thirst with median scores of 2 out of 6 (range 0-4). We assume that during a 12-h period, a work scheme that consists of a 3-h shift in FFP2/PPE and a 3-h rest period (working without FPP2/PPE) is a reliable and safe solution for HCPs working in specialized COVID-19 referral hospitals.

Sterilization Induced Changes in Polypropylene-Based Ffp2 Masks.

In the context of the SARS-CoV2 pandemic and because of the surgical and FFP2 mask (equivalent to the American N95 masks) shortages, studies on efficient sterilization protocols were initiated. As sterilization using irradiation is commonly used in the medical field, this method was among those that were evaluated. In this work, we tested irradiation under vacuum and under air (under both γ-rays and e-beams), but also, for acceptance purposes, undertook washing prior to the e-beam irradiation sterilization process. This article deals with the modifications induced by the sterilization processes at the molecular and the macromolecular scales on an FFP2 mask. Fourier transform infrared spectroscopy in attenuated total reflectance mode, size-exclusion chromatography and thermal-desorption-gas chromatography-mass spectrometry were used to characterize possible damage to the materials. It appeared that the modifications induced by the different sterilization processes under vacuum were relatively tenuous and became more significant when irradiation was performed using γ-rays under air.

Impact of washing cycles on the performances of face masks.

The tension on the supply of surgical and FFP2 masks during the first wave of the COVID-19 pandemic leads to study the potential reuse of these masks. As washing is easily adaptable at home, this treatment solution was retained. In this work, thirty-six references of surgical masks and four FFP2 masks were tested without being worn or washed and after several washing cycles. The results highlighted a great heterogeneity of performances depending on the mask trademarks, both for surgical masks and FFP2. The quality of the meltblown and spunbond layers and the presence/absence of electrostatic charges at the fiber surface are put forward to explain the variability of results, both on differential pressures and filtration efficiencies. The differential pressure and the particle filtration efficiency of the washed masks were maintained up to 10 washing cycles and met the standard requirements. However, an immersion in water with a detergent induces an efficiency decrease for submicronic particles. This lower performance, constant after the first washing cycle, can be explained by the loss of electrostatic charges during the washing cycle. The modifications of surface properties after washing also lead to a loss of the hydrophobic behavior of type IIR surgical masks, which can therefore no more be considered as resistant to blood projections.

Determination of hydrogen peroxide on N95 masks after sanitization using a colorimetric method.

Hydrogen peroxide is commonly used as a sterilizing agent for medical devices and its use has recently been extended to N95 masks during PPE shortages as a result of the COVID-19 pandemic. The hydrogen peroxide remaining on the masks after sterilization could potentially pose a health hazard to the mask users. In the present study a colorimetric method was optimized for the determination of hydrogen peroxide on N95 masks following chemical sanitizations. The developed analytical method demonstrated an overall recovery of 98% ± 7%. The limit of detection ranged from 0.16 to 0.25 mg/mask, depending on the type of mask. The expanded measurement uncertainty was 13% (at a 95% confidence interval). The sanitization process itself introduced a significant variation in hydrogen peroxide load between masks. The ozone used in the sanitization process had no significant impact on analytical performance. Stamped and printed marks on the mask surfaces could induce biased readings. Hydrogen peroxide decomposes quickly on the mask surfaces so timing of analysis is an important factor in method standardization.•The validation data demonstrated that the in-house method is reliable and fit for the intended purpose, offering a sensitive, simple, rapid, and inexpensive method of residue monitoring.