Masking Protection Research Articles

467 Analysis of Surgical Smoke Generated by Electrocautery and Standard Surgical Mask Protection in a Simulated Neurosurgical Operating Room Using a Post-mortem Porcine Model for Laminectomy Exposures

INTRODUCTION: Electrocautery is a widely used tool to coagulate and separate tissue during neurosurgical procedures. Surgical smoke generated by electrocautery has harmful properties if inhaled over long-term. To our knowledge, no efforts have been made within the neurosurgery field to investigate the air quality of operating rooms (OR) where neurosurgical procedures are being performed. METHODS: Four freshly post-mortem porcine models were used to perform 4 laminectomy exposures measuring 20cm using electrocautery in a simulated neurosurgical OR. Air sampling media and pumps were connected to a 3D-printed human face model. In 2 models the face was covered with a standard surgical mask, and in 2 models no masks were placed. The models were positioned at 40 cm distance from the surgical field. Air samples were analyzed by an independent laboratory. Analyses of total amount of respirable dust and 31 VOCs were conducted. The mean total amount between each 2 samples of the masked vs non-masked models were compared. RESULTS: On all 2 masked and 2 non-masked models, all 31 VOCs were below the levels of quantitation. On the 2 non-masked models, the total amount of respirable dust were 8.2 times higher than in the 2 masked models. CONCLUSIONS: Total amount of VOCs appears to be low at the distance measured regardless of mask use, however further studies are needed to determine if even small amounts can still be harmful over time. Standard surgical masks seem to be efficient in protecting against the high amounts of respirable dust generated by surgical smoke.

Enhancing Face Mask Protection: Graphene Oxide Modification for Improved Filtration and Electrostatic Charge

Enhancing Face Mask Protection: Graphene Oxide Modification for Improved Filtration and Electrostatic Charge

Unveiling the Investigation and Comfort Research in Various Scenarios of Mask Protection Equipment against Respiratory Transmission

Unveiling the Investigation and Comfort Research in Various Scenarios of Mask Protection Equipment against Respiratory Transmission

Investigation of Mask Protection Efficiency and associated Respiratory Deposition in Occupational Aerosol Exposure for Dental Hygienists

Investigation of Mask Protection Efficiency and associated Respiratory Deposition in Occupational Aerosol Exposure for Dental Hygienists

Research on group distribution leakage analysis method for RSM

Side channel attack is a new and simple attack idea, and its proposal has created a significant threat to the security of cryptographic devices. With the continuous development of deep learning techniques, deep learning-based side channel attacks have enabled the attack techniques to reach new heights, but the attack efficiency and training time have become new problems. In order to improve the attack efficiency, researchers have proposed a large number of leakage analysis methods, which can effectively extract the intervals with significant leakage in the energy consumption curve and reduce the training parameters and data volume. In order to deal with side channel attacks, researchers have proposed various resistance strategies, among which masking protection is the simplest and widely used way. RSM rotating S-box masking scheme is a particularly important masking protection scheme, which uses a first-order masking scheme to randomize the leakage energy consumption of sensitive information using random masks, thus making the algorithm resistant to first-order side channel attacks. For this type of masking algorithm, this paper proposes a new leakage analysis algorithm, namely "Group Distribution Difference" (GDD). This algorithm is based on the distribution difference of energy consumption, and the energy consumption frequency in the group is calculated instead of the probability distribution. The KL distance is used to calculate the difference between groups and find out the leakage interval, so as to achieve an efficient attack.

Coronavirus Mask Protection Algorithm: A New Bio-inspired Optimization Algorithm and Its Applications.

Nowadays, meta-heuristic algorithms are attracting widespread interest in solving high-dimensional nonlinear optimization problems. In this paper, a COVID-19 prevention-inspired bionic optimization algorithm, named Coronavirus Mask Protection Algorithm (CMPA), is proposed based on the virus transmission of COVID-19. The main inspiration for the CMPA originated from human self-protection behavior against COVID-19. In CMPA, the process of infection and immunity consists of three phases, including the infection stage, diffusion stage, and immune stage. Notably, wearing masks correctly and safe social distancing are two essential factors for humans to protect themselves, which are similar to the exploration and exploitation in optimization algorithms. This study simulates the self-protection behavior mathematically and offers an optimization algorithm. The performance of the proposed CMPA is evaluated and compared to other state-of-the-art metaheuristic optimizers using benchmark functions, CEC2020 suite problems, and three truss design problems. The statistical results demonstrate that the CMPA is more competitive among these state-of-the-art algorithms. Further, the CMPA is performed to identify the parameters of the main girder of a gantry crane. Results show that the mass and deflection of the main girder can be improved by 16.44% and 7.49%, respectively.

Comparative Mask Protection against Inhaling Wildfire Smoke, Allergenic Bioaerosols, and Infectious Particles.

This work compares relative mask inhalation protection against a range of airborne particle sizes that the general public may encounter, including infectious particles, wildfire smoke and ash, and allergenic fungal and plant particles. Several mask types available to the public were modeled with respirable fraction deposition. Best-case collection efficiencies for cloth, surgical, and respirator masks were predicted to be lowest (0.3, 0.6, and 0.8, respectively) for particle types with dominant sub-micrometer modes (wildfire smoke and human-emitted bronchial particles). Conversely, all mask types were predicted to achieve good collection efficiency (up to ~1.0) for the largest-sized particle types, including pollen grains, some fungal spores, and wildfire ash. Polydisperse infectious particles were predicted to be captured by masks with efficiencies of 0.3-1.0 depending on the pathogen size distribution and the type of mask used. Viruses aerosolized orally are predicted to be captured efficiently by all mask types, while those aerosolized from bronchiolar or laryngeal-tracheal sites are captured with much lower efficiency by surgical and cloth masks. The predicted efficiencies changed very little when extrathoracic deposition was included (inhalable rather than respirable fraction) or when very large (100 µm) particles were neglected. Actual mask fit and usage will determine protection levels in practice, but the relative comparisons in this work can inform mask guidance for different inhalation hazards, including particles generated by yard work, wildfires, and infections.

IoT-Based Smart Mask Protection against the Waves of COVID-19.

In the year 2020, the word “pandemic” has become quite popular. A pandemic is a disease that spreads over a wide geographical region. The massive outbreak of coronavirus popularly known as COVID-19 has halted normal life worldwide. On 11th March 2020, the World Health Organization (WHO) quoted the COVID-19 outbreak as a “Pandemic”. The outbreak pattern differs widely across the globe based on the findings discovered so far; however, fever is a common and easily detectable symptom of COVID-19 and the new COVID strain. After the virus outbreak, thermal scanning is done using infrared thermometers in most public places to detect infected persons. It is time-consuming to track the body temperature of each person. Besides, close contact with infected persons can spread the virus from the infected persons to the individual performing the screening or vice-versa. In this research, we propose a device architecture capable of automatically detecting the coronavirus or new COVID strain from thermal images; the proposed architecture comprises a smart mask equipped with a thermal imaging system, which reduces human interactions. The thermal camera technology is integrated with the smart mask powered by the Internet of Things (IoT) to proactively monitor the screening procedure and obtain data based on real-time findings. Besides, the proposed system is fitted with facial recognition technology; therefore, it can also display personal information. It will automatically measure the temperature of each person who came into close contact with the infected humans or humans in public spaces, such as markets or offices. The new design is very useful in healthcare and could offer a solution to preventing the growth of the coronavirus. The presented work hasa key focus on the integration of advanced algorithms for the predictive analytics of parameters required for in-depth evaluations. The proposed work and the results are pretty effectual and performance cognizant for predictive analytics. The manuscript and associated research work integrate the IoT and Internet of Everything (IoE) based analytics with sensor technologies with real-time data so that the overall predictions will be more accurate and integrated with the health sector.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12652-022-04395-7.

Mask Protection Against Lead Exposure and Its Correlation with Erythropoiesis in Automotive Body Painters at Ligu District, Semarang, Indonesia.

IntroductionAutomotive body painters are at risk of excessive lead exposure that may compromise their health. This study examined the protective effects of masks against lead exposure and its correlation with blood profile of automotive body painters at Ligu district, Semarang, Indonesia.Material and MethodsThis cross-sectional study included 61 painters at Ligu district, Semarang, Indonesia (mean age 45 years, 100% male). Mask use was categorized into “frequent” and “infrequent”. Blood samples were taken to measure lead exposure and haematological parameters (haemoglobin/HGB, erythrocytes/RBC, haematocrit/HCT, mean corpuscular haemoglobin/MCH, mean corpuscular volume/MCV, mean corpuscular haemoglobin concentration/MCHC). Effectivity of mask use against lead exposure was analysed with Fisher’s exact test, while lead exposure and haematopoietic parameters were evaluated with Pearson’s correlation tests.ResultsThere were 26 automotive painters (42.6%) classified as unfrequent mask users, and all of them had high blood lead levels. Most haematopoiesis parameters were in normal range. Workers with infrequent mask use were 1.269 more likely to be exposed to lead compared to those with frequent mask use (CI 95%, 1.082–1.552). Significant associations were found between lead exposure and RBC (p=0.0, r=−0.53), HGB (p=0, r=−0.61), and HCT (p=0.00, r=−0.61). No significant correlations were observed between lead exposure and MCV, MCH, MCHC.ConclusionLead exposure was significantly associated with haematological parameters RBC, HGB, and HCT, confirming the effects of prolonged exposure on blood profile. However, mask use provided significant protection against lead exposure in automotive body painters and should be an obligatory gear for workers.

170. Reduction in Bloodborne Pathogen Splash Exposures After Implementation of Universal Masking and Eye Protection for COVID-19

BackgroundWhile splashes to the eyes, nose and mouth can often be prevented through appropriate personal protective equipment (PPE) use, they continue to occur frequently when PPE is not used consistently. Due to the COVID-19 pandemic, we implemented universal masking and eye protection for all healthcare personnel (HCP) performing direct patient care and observed a subsequent decline in bloodborne pathogen (BBP) splash exposures. MethodsOur healthcare system, employing >12,000 healthcare personnel (HCP), implemented universal masking in April 2020 and eye protection in June 2020. We required HCP to mask at all times, and use a face shield, safety glasses or goggles when providing direct patient care. Occupational Safety tracked all BBP exposures due to splashes to the eyes, nose, mouth and/or face, and compared exposures during 2020 to those in 2019. We estimated costs, including patient and HCP testing, related to splash exposures, as well as the additional cost of PPE incurred.ResultsIn 2019, HCP reported 90 splashes, of which 57 (63%) were to the eyes. In 2020, splashes decreased by 54% to 47 (36 [77%] to eyes). In both years, nurses were the most commonly affected HCP type (62% and 72%, respectively, of all exposures). Physicians (including residents) had the greatest decrease in 2020 (10 vs. 1 splash exposures [90%]), while nurses had a 39% decrease (56 vs. 34 exposures). Nearly all of the most common scenarios leading to splash exposures declined in 2020 (Table). We estimated the cost of each BBP exposure as &2,940; this equates to a savings of &123,228. During 2020, we purchased 65,650 face shields, safety glasses and goggles (compared to 5303 similar items in 2019), for an additional cost of &238,440.Specific activities identified as leading to bloodborne pathogen splash exposures, 2019 vs. 2020. ConclusionWe observed a significant decline in splash-related BBP exposures after implementing universal masking and eye protection for the COVID-19 pandemic. While cost savings were not observed, we were unable to incorporate the avoided pain and emotional trauma for the patient, exposed HCP, and coworkers. This unintended but positive consequence of the COVID-19 pandemic exemplifies the need for broader use of PPE, particularly masks and eyewear, for all patient care scenarios where splashes may occur.Disclosures All Authors: No reported disclosures

400. Impact of SARS-CoV-2 Test-based Strategy to Reduce Quarantine Days Among Asymptomatic Healthcare Workers After Household Exposure

BackgroundAppropriate staffing is essential to provide safe patient care. During the COVID-19 pandemic, healthcare workers (HCWs) are missing work days due to illness or high-risk exposure (HRE) to an infected person. To avoid staffing shortages, we implemented a SARS-CoV-2 test-based strategy among asymptomatic HCWs after HRE to facilitate early return to work.MethodsIn July 2020, our institution implemented a SARS-CoV-2 RT-PCR test-based strategy among HCWs within 7 days of HRE. HCWs were defined as any paid or unpaid persons directly or indirectly involved in patient care. HRE was defined as close contact < 6 feet with an infected household member without use of mask and lasting for ≥ 15 minutes. Contact with a patient or coworker was not considered high-risk due to universal masking and eye protection use. HCWs underwent SARS-CoV-2 RT PCR testing of a nasopharyngeal swab at least once (1-2 days post-exposure) or twice (5-7 days post-exposure). HCWs with symptoms at baseline were excluded. HCWs who were asymptomatic during evaluation were considered as truly asymptomatic (TA). Saved work-days (SWD) were calculated based on number of days saved due to testing strategy compared to the Centers for Disease Control and Prevention’s recommended 14-day quarantine. HCWs were allowed to return to work within 7 days of HRE if they tested negative, or after completing 10-day isolation period ± improvement in symptoms from symptom onset if they tested positive.ResultsBetween 07/01/2020 to 12/31/2020, 450 unique asymptomatic HCWs underwent SARS-CoV-2 testing. Of those, 84% were women and median age was 36 years, 347 tested negative and 103 tested positive. Of those positives, 33% of HCWs tested positive on day 2 after HRE with 141 SWDs (average 2 days/person). Only 37% were TA positives. Of those negatives, 94% were TA SARS-CoV-2 negative with 2620 SWDs (average 7.5 days/person). There were no healthcare outbreaks related to HCWs allowed to return to work following this strategy. Asymptomatic healthcare workers commonly tested positive for SARS-CoV-2 on day 2 from household exposure compared to other daysConclusionTest-based strategy among asymptomatic HCWs with HRE reduced loss of workdays and helped limit staffing shortages. Majority of positive HCWs developed symptoms after positive SARS-CoV-2 testing, which may support allowing most fully vaccinated HCWs with no COVID-like symptoms to continue to work unless symptomatic.Disclosures All Authors: No reported disclosures

423. Implementation of a Hierarchy of Controls in a Mobile Health Unit to Safely Care for Inpatients with COVID-19 during Healthcare System Surge

BackgroundIn April 2021, Sunnybrook Health Sciences Centre opened a Mobile Health Unit (MHU, i.e. medical tents) under the direction of the Ontario Ministry of Health and Long Term Care in response to a surge in hospitalized patients with COVID-19 during wave three of the pandemic. Providing care to patients in non-conventional spaces is not new, however, experience in safely caring for COVID-19 patients in these settings is lacking. Our aim is to describe the implementation of our MHU and associated outcomes of these COVID-19 patients.MethodsA multidisciplinary clinical and operations team was created to plan, execute and operate a safe environment for COVID-19 patients and healthcare workers within the MHU. Patient selection was restricted to patients with COVID-19 who were clinically recovering from severe COVID-19 pneumonia. Ventilation was optimized with air flow directed away from patient areas, velocity reduced to below 0.25 meters per second, and air exchanges of 24-28 per hour. All healthcare workers working in the MHU were offered COVID-19 vaccine and required to complete mandatory education if they declined (vaccination rate of 87% was achieved among dedicated staff). Universal masking and eye protection was used throughout the MHU with designated areas for donning and doffing personal protective equipment. ResultsIn total, 32 patients with COVID-19 were managed in the MHU between 26 April and 21 May, 2021. Table 1 provides the summary of patient characteristics. All patients had a median of one-day of transmission-based precautions remaining in their course and were infected with Alpha variant with exception of one patient with the Gamma variant. Among those patients with genotyping available, all were infected with SARS-CoV-2 carrying the N501Y mutation. Four of the 32 patients required transfer to the main hospital for medical indication while the others were discharged home or to rehabilitation. None of the healthcare workers who worked within the MHU developed COVID-19 infection. ConclusionWe safely cared for patients recovering from COVID-19 infection in an MHU to support system healthcare capacity. Our experience, including the specific hierarchy of controls implemented, may be helpful for future pandemic planning.Disclosures All Authors: No reported disclosures

Double masking protection vs. comfort-A quantitative assessment.

COVID-19 has forced humankind to adopt face masks as an integral part of everyday life. This preventive measure is an effective source control technique to curb the spread of COVID-19 and other similar diseases. The virus responsible for causing COVID-19 has undergone several mutations in the recent past, including B.1.1.7, B.1.351, P.1, and N501Y, B.1.617, with a higher infectious rate. These viruses' variants are mainly responsible for the recent spike in COVID-19 cases and associated steep rise in mortality rate worldwide. Under these circumstances, the Center for Disease Control (CDC) and health experts recommend double masking, which mainly includes a surgical mask and a cotton mask for the general public. This combination provides an additional layer of protection and masks fitment to minimize the leakage of droplets expelled during coughing, sneezing, talking, and breathing. This leakage may cause airborne transmission of the virus. In the present study, we report a systematic quantitative unsteady pressure measurement supplement with flow visualization to quantify the effectiveness of a single and double mask. We have also evaluated double masking consisting of a surgical mask and an N-95 mask used by medical professionals. A simple knot improves the surgical mask fitment significantly, and hence, the leakage of droplets is minimized. The leakage of the droplets was reduced to a large extent by using a double mask combination of a two-layer cotton mask over the surgical mask with a knot. The double mask combination of surgical + N-95 and two-layer cotton + N-95 masks showed the most promising results, and no leakage of the droplets is observed in the forward direction. A double mask combination of surgical and N-95 mask offers 8.6% and 5.6% lower mean and peak pressures compared to surgical, and cotton mask. The best results are observed with cotton and N-95 masks with 54.6% and 23% lower mean and peak pressures than surgical and cotton masks; hence, this combination will offer more comfort to the wearer.

Covid-19: Face Mask Protection in the Pediatric Setting

Covid-19: Face Mask Protection in the Pediatric Setting

Mask protection against bioaerosols

Mask protection against bioaerosols

Mask protection against bioaerosols

Mask protection against bioaerosols

Explaining coherence in coherence masking protection for adults and children

Coherence masking protection (CMP) is the phenomenon in which a low-frequency target (typically a first formant) is labeled accurately in poorer signal-to-noise levels when combined with a high-frequency cosignal, rather than presented alone. An earlier study by the authors revealed greater CMP for children than adults, with more resistance to disruptions in harmonicity across spectral components [Nittrouer and Tarr (2011). Atten. Percept. Psychophys. 73, 2606-2623]. That finding was interpreted as demonstrating that children are obliged to process speech signals as broad spectral patterns, regardless of the harmonic structure of the spectral components. The current study tested three alternative, auditory explanations for the observed coherence of target + cosignal: (1) unique spectral shapes of target + cosignal support labeling, (2) periodicity of target + cosignal promotes coherence, and (3) temporal synchrony across target + cosignal reinforces temporal expectancies. Adults, eight-year-olds, and five-year-olds labeled stimuli in five conditions: F1 only and F1 + a constant cosignal (both used previously) were benchmarks for comparing thresholds for F1 + 3 new cosignals. Children again showed greater CMP than adults, but none of the three hypotheses could explain their CMP. It was again concluded that children are obliged to recognize speech signals as broad spectral patterns.

Coherence masking protection for mid-frequency formants by adults and children

Coherence masking protection (CMP) refers to the phenomenon in which a target formant is labeled at lower signal-to-noise levels when presented with a stable cosignal consisting of two other formants than when presented alone. This effect has been reported primarily for adults with first-formant (F1) targets and F2/F3 cosignals, but has also been found for children, in fact in greater magnitude. In this experiment, F2 was the target and F1/F3 was the cosignal. Results showed similar effects for each age group as had been found for F1 targets. Implications for auditory prostheses for listeners with hearing loss are discussed.

Coherence masking protection for speech in children and adults

In three experiments, we tested the hypothesis that children are more obliged than adults to fuse components of speech signals and asked whether the principle of harmonicity could explain the effect or whether it is, instead, due to children’s implementing speech-based mechanisms. Coherence masking protection (CMP) was used, which involves labeling a phonetically relevant formant (the target) presented in noise, either alone or in combination with a stable spectral band (the cosignal) that provides no additional information about phonetic identity and is well outside the critical band of the target. Adults and children (8 and 5 years old) heard stimuli that were either synthetic speech or hybrids consisting of sine wave targets and synthetic cosignals. The target and cosignal either shared a common harmonic structure or did not. An adaptive procedure located listeners’ thresholds for accurate labeling. Lower thresholds when the cosignal is present indicate CMP. Younger children demonstrated CMP effects that were both larger in magnitude and less susceptible to disruptions in harmonicity than those observed for adults. The conclusion was that children are obliged to integrate spectral components of speech signals, a perceptual strategy based on their recognition of when all components come from the same generator.

Why diverse spectral structure coheres for children.

Coherence masking protection (CMP) refers to the phenomenon in which lower thresholds for accurate vowel labeling are obtained when an informative F1 is presented with a constant, and therefore non-informative, F2/F3 cosignal than when F1 is alone. Tarr and Nittrouer reported this effect for adults and showed enhanced effects for children with synthetic speech [J. Acoust. Soc. Am. 126, S2300 (2009)]. With sine waves, no CMP was found for either group. Two new experiments asked what accounts for these differences across age and stimulus type. Hypotheses focused on the principle of common harmonic structure and expectations of speech-like signals. Experiment 1 combined sine-wave F1 with three synthetic cosignals, one that was harmonically related to F1 and two that were not. Experiment 2 used all synthetic speech, but F1 and the cosignal differed in harmonic structure. All signals were speech-like. Stimuli were presented in white noise for labeling, with and without the cosignal. Labeling thresholds were measured adaptively for F1 only and all three formants. Adults showed no significant CMP in either condition, but children did in both. It was concluded that children perceptually organize auditory signals based on the expectation of speech and do not require harmonicity. [NIDCD grant DC-00633.]