Respiratory Protection Research Articles

Effect of PM2.5 air pollution on the incidence of respiratory diseases: A Python-based data analysis

Air pollution is a global problem and a serious threat to public health. According to the World Health Organization, 99 percent of the world's population lives in places where air quality guideline standards are exceeded, resulting in 4.2 million premature deaths each year. Air pollution not only leads to respiratory diseases such as respiratory infections, asthma, and chronic obstructive pulmonary disease (COPD), but is also associated with chronic non-communicable diseases such as lung cancer, cardiovascular disease, and diabetes. This study analysed the relationship between the air quality index (AQI) and the incidence of respiratory diseases and found a positive correlation, i.e., the worse the air quality, the more respiratory diseases. This result is consistent with other studies and with the mechanism of the adverse effects of air pollution on the respiratory system. Therefore, this study is important for raising public awareness of the hazards of air pollution and promoting air quality improvement and respiratory health protection. This study also provides valuable information for environmental policy makers to help them consider the impacts of air quality on public health more comprehensively. This study used randomly generated data, so the results may not fully reflect what happens in the real world. Future studies need to use real environmental and health data to validate and extend our findings and provide a more sophisticated model for scenario simulation and analysis.

Design and testing of a sew-free origami mask for improvised respiratory protection

Respiratory aerosols with diameters smaller than 100 μm have been confirmed as important vectors for the spread of diseases such as SARS-CoV-2. While disposable and cloth masks afford some protection, they are typically inefficient at filtering these aerosols and require specialized fabrication devices to produce. We describe a fabrication technique that makes use of a folding procedure (origami) to transform any filtration material into a mask. These origami masks can be fabricated by non-experts at minimal cost and effort, provide adequate filtration efficiencies, and are easily scaled to different facial sizes. Using a mannequin fit test simulator, we demonstrate that these masks can provide filtration efficiencies of over 90% while simultaneously providing greater comfort as demonstrated by pressure drops of <20 Pa. We also quantify mask leakage by measuring the variations in filtration efficiency and pressure drop when masks are sealed to the mannequin face compared to when the mask is unsealed but positioned to achieve the best fit. While leakage generally trended with pressure drop, some of the best performing mask media achieved <10% reduction in filtration efficiency due to leakage. Because this mask can provide high filtration efficiencies at low pressure drop compared to commercial alternatives, it is likely to promote greater mask wearing tolerance and acceptance.

An After-Action Review of the Implementation of a Statewide Respiratory Protection Program- Perspectives from Fit Test Assessors and Program Leads

An After-Action Review of the Implementation of a Statewide Respiratory Protection Program- Perspectives from Fit Test Assessors and Program Leads

Water-blocking Asphyxia of N95 Medical Respirator During Hot Environment Work Tasks With Whole-body Enclosed Anti-bioaerosol Suit

BackgroundDuring hot environment work tasks with whole-body enclosed anti-bioaerosol suit, the combined effect of heavy sweating and exhaled hot humid air may cause the N95 medical respirator to saturate with water/sweat (i.e., water-blocking). Methods32 young male subjects with different body mass indexes (BMI) in whole-body protection (N95 medical respirator + one-piece protective suit + head covering + protective face screen + gloves + shoe covers) were asked to simulate waste collecting from each isolated room in a seven-story building at 27-28°C, and the weight, inhalation resistance (Rf), and aerosol penetration of the respirator before worn and after water-blocking were analyzed. ResultsAll subjects reported water-blocking asphyxia of the N95 respirators within 36-67 min of the task. When water-blocking occurred, the Rf and 10-200 nm total aerosol penetration (Pt) of the respirators reached up to 1270-1810 Pa and 17.3-23.3%, respectively, which were 10 and 8 times of that before wearing. The most penetration particle size of the respirators increased from 49-65 nm before worn to 115-154 nm under water-blocking condition, and the corresponding maximum size-dependent aerosol penetration increased from 2.5-3.5% to 20-27%. With the increase of BMI, the water-blocking occurrence time firstly increased then reduced, while the Rf, Pt, and absorbed water all increased significantly. ConclusionsThis study reveals respirator water-blocking and its serious negative impacts on respiratory protection. When performing moderate-to-high-load tasks with whole-body protection in a hot environment, it is recommended that respirator be replaced with a new one at least every hour to avoid water-blocking asphyxia.

Wet-resistant, dustproof, and germproof self-powered lignocellulosic triboelectric filters for respiratory protection, monitoring, and diagnosis

The moisture sensitivity and structural defects found in natural cellulose materials limit their ability to serve as substitutes for petroleum-based masks. This study uses a combination of methods, including retaining lignin, embedding silver particles in situ, and using a mixture of coarse and fine fibers to enhance the wet resistance, antibacterial properties, and triboelectric output of lignocellulosic materials. This approach also aimed to balance pressure drop and filtration efficiency. A triboelectric filter (Ag-LCTEF) using a perforated fluorinated ethylene propylene (FEP) film sandwiched between two sheets of Ag-embedded lignocellulose (Ag-LC) was assembled. The resulting Ag-LCTEF enabled self-powered continuous monitoring of breathing signals, boasting impressive submicron particle removal (99.70 %) and antibacterial efficiency (99.18 %), all while maintaining a relatively low-pressure drop of 76 Pa. Notably, the Ag-LCTEF displayed consistent performance and long-term durability even in high humidity conditions of 80 % RH. These remarkable achievements have spurred the suggestion of integrating respiratory protection, monitoring, and diagnostic functions, showcasing its potential for the next generation of wearable electronics. Moreover, naturally safe and biodegradable lignocellulose serves as an environmentally friendly replacement for petroleum-based materials.

Tuberculosis Infection Control & Hygiene - Recommendations of the DZK

Preventing the spread of the disease is an essential goal in the care and treatment of tuberculosis. In addition to early diagnosis and effective therapies, isolation of infectious patients and adequate hygiene measures are of particular importance for infection prevention. The present recommendations replace the previous recommendations "tuberculosis infection control" from 2012 and take into account the current national and international recommendations and as well as new scientific findings. After a description of the infection and the transmission pathways, the necessary prevention and hygiene measures in health care facilities are comprehensively presented. Since the last revision of the recommendations on infection prevention, international recommendations and the KRINKO recommendation on ending isolation have been changed. In accordance with this, under certain conditions in the case of sensitive tuberculosis, de-isolation in health care facilities can take place after 14 days without taking the sputum findings into account. The second part of the recommendations explains in detail the measures to be taken in special situations and areas, such as general practitioners, ambulance services and care facilities. Here, the recommendations on respiratory protection have been simplified; for staff, an FFP2 mask is now generally considered sufficient.

Advanced cartridge design for a gas respiratory protection system using experiments, CFD simulation and virtual reality

Gas masks are critical for protection against chemical, biological, radiological, and nuclear materials. Efforts are underway to develop advanced cartridges for next-generation gas respirators in civil-military combined use to improve wearability and protection for users (firefighters, military personnel, and environmental and safety-related workers). Herein, the performance of three newly designed cartridges for a next-generation gas respirator was evaluated using flow analysis, along with adsorption characteristics. The adsorption kinetics of cyclohexane gas on ASC (a copper-silver-hexavalent chromium impregnated activated carbon in the study) was measured by breakthrough experiments in a packed bed, and the obtained parameters were used in the computational fluid dynamics (CFD) model for the designed plate-type cartridges. To apply the physical properties of the adsorbent to the CFD simulation, porous materials were expressed using the granular technique and packed bed technique. The CFD model was verified through a gas adsorption experiment using a prototype cartridge. The respiration resistance and breakthrough time for the filled-adsorbent efficiency and lifespan were compared among the three designed cartridges according to the gas inflow conditions. Additionally, virtual engineering was performed by grafting the CFD results to a virtual reality (VR) system with which 3-dimensional performance visuals of the cartridges could be observed. The developed VR system provides detailed information for cartridge design and optimization. Overall, the developed procedure of virtual engineering can be used to improve CFD simulation results.

Risk Assessment of Coronavirus Disease (COVID-19) Transmission among Physicians Working at a COVID-dedicated Tertiary-care Hospital

Background and aims: In the earlier stage of pandemic, a sizeable number of physicians and other healthcare workers were infected with SARS-CoV-2. The aim of this study was to assess the factors associated with the risk of SARS-CoV-2 infection among physicians working at a COVID-dedicated tertiary care hospital, within and outside the medical workplace.&#x0D; Methods: This case control study was conducted among the physicians and surgeons working at different departments of Mugda Medical College and Hospital and undergone different pattern of exposure to COVID patients within the period of 20 April, 2020 and 20 July, 2020. Respondents were queried regarding job description, workplace exposures, respiratory protection, hospital policy of disease prevention, and extra-occupational activities during duty period. Chi-square test was done and odds ratios for physicians’ infection were calculated. A p-value &lt;0.05 was considered as statistical significant.&#x0D; Results: Increased risk of SARS-CoV-2 infection in physicians was associated with the use of mobile phone during duty hour (OR, 15, 95% confidence interval 1.971 to 121.905, p=0.001), and breech of PPE during doffing (OR, 2.52, 95% confidence interval 0.821 to 7.76, p=0.099). Extra-occupational risk factors included contact with known COVID patient (OR, 5.735, 95% confidence interval 2.072 to 15.872, p=&lt;0.001), and visit any gathering (OR, 1.076, 95% confidence interval 0.412 to 2.81, p=0.881). Physicians worked in roster group (50%) and round group (34.38%) were mostly infected than other facilities.&#x0D; Conclusion: COVID-19 transmissions to physicians was associated with exposure at workplace, breech in PPE during doffing, use of device during round/roster period, extra-occupational exposure to known COVID patients outside the hospital, and visit any gathering. Close monitoring of infection control measures in workplace and increase awareness of the risks of outdoor activities in pandemic situation, may reduce the incidence of infection among physicians.&#x0D; Mugda Med Coll J. 2022; 5(2): 93-97

Health effects of filtering facepiece respirators: Research and clinical implications of comfort, thermal, skin, psychologic, and workplace effects.

Filtering facepiece respirators (FFR's) such as N95s have become widely used in appropriate settings for personal respiratory protection and are increasingly used beyond workplace settings. Concerns about possible adverse effects have appeared in many publications, particularly since the COVID-19 pandemic led to much more widespread use. This paper synthesizes known effects based upon review of publications in PubMed since 1995, addressing effects other than pulmonary and cardiovascular (reviewed elsewhere). Findings: (1) Subjective discomfort is very frequently reported; this includes general discomfort or organ-system-specific complaints such as respiratory, headache, dermatologic, and heat. Research methods are widely divergent, and we propose a taxonomy to classify such studies by methodology, study population (subjects, experimental vs. observational methodology, comparator, specificity, and timeframe) to facilitate synthesis. (2) Objective measures of increased heat and humidity within the mask are well documented. (3) Frequency and characteristics of dermatologic effects have been insufficiently evaluated. (4) Physical mask designs are varied, making generalizations challenging. (5) More studies of impact on work performance and communication are needed. (6) Studies of effect of FFR design and accompanying training materials on ease and consistency of use are needed.

Prompt design of direction air supply using CFD-based proper orthogonal decomposition method considering locally dense sample distribution

Achieving long-lasting and effective respiratory protection in highly polluted industrial sites with a cost of a small amount of air, particularly during mobile operations by workers, poses a challenge. Direction air supply (DAS) has been developed to address this challenge. However, the trial-and-error design of DAS parameters is computationally expensive and often leads to inaccurate optimizations. This work proposes a prompt inverse design method for DAS based on proper orthogonal decomposition (POD). The data structure of this work is compatible with Hermite interpolation. Furthermore, an innovative approach is introduced, utilizing a locally dense strategy for sample distribution to enhance optimization reliability. The accuracy of the CFD-based POD method for reconstructing concentration fields is verified by comparing the deviation and Pearson correlation coefficient of the predicted concentration with simulated data. The optimal DAS parameters for three target protection areas are determined through a traversal-screening process, under dual constraint indexes of protection factor and DAS air volume. In addition, the typical concentration structures extracted using POD and the sample saturation are discussed. The findings of this work contribute to a broader application of DAS in industrial sites.

Examining the Roles of Training, Fit Testing, and Safety Climate on User Confidence in Respiratory Protection: A Case Example with Reusable Respirators in Health Delivery Settings.

A lack of confidence in the efficacy of respiratory protection can contribute to uncertainty among workers and cast doubt on workplace safety. To date, no research has been conducted to study and understand the introduction of elastomeric half-mask respirators (EHMRs)-without exhalation valves (EVs) or with exhalation valve filters (EVFs), both representing new designs that address source control-in the workplace. To study this issue, researchers collaborated with partners at 32 health delivery settings that received EHMRs from the Strategic National Stockpile during the COVID-19 pandemic. EHMR users (n = 882) completed an online survey between October 2021 and September 2022. Analyses demonstrated that employees were statistically significantly more confident in the efficacy of EHMRs with no EV/with an EVF (including the efficacy in protecting the user from COVID-19) if they had been fit tested and received training. Respondents were also statistically significantly more confident in the efficacy of their EHMR if they had a more positive perception of their organization's safety climate. The results provide insights for tailored fit testing and training procedures as manufacturers continue to improve respirator models to enhance worker comfort and use. Results also show that, even during a public health emergency, the role of safety climate cannot be ignored as an organizational factor to support worker knowledge, attitudes, and participation in health and safety behaviors specific to respirator use.

Revisiting the personal protective equipment components of transmission-based precautions for the prevention of COVID-19 and other respiratory virus infections in healthcare.

The COVID-19 pandemic highlighted some potential limitations of transmission-based precautions. The distinction between transmission through large droplets vs aerosols, which have been fundamental concepts guiding infection control measures, has been questioned, leading to considerable variation in expert recommendations on transmission-based precautions for COVID-19. Furthermore, the application of elements of contact precautions, such as the use of gloves and gowns, is based on low-quality and inconclusive evidence and may have unintended consequences, such as increased incidence of healthcare-associated infections and spread of multidrug-resistant organisms. These observations indicate a need for high-quality studies to address the knowledge gaps and a need to revisit the theoretical background regarding various modes of transmission and the definitions of terms related to transmission. Further, we should examine the implications these definitions have on the following components of transmission-based precautions: (i) respiratory protection, (ii) use of gloves and gowns for the prevention of respiratory virus infections, (iii) aerosol-generating procedures and (iv) universal masking in healthcare settings as a control measure especially during seasonal epidemics. Such a review would ensure that transmission-based precautions are consistent and rationally based on available evidence, which would facilitate decision-making, guidance development and training, as well as their application in practice.

Investigation of arranging doctor schedules during the COVID-19 outbreak by using a decision support system

People with minor symptoms are isolated at home, while those with severe symptoms are treated in hospitals. The hospital burden has so increased excessively. Healthcare workers experience physical tiredness as a result of stress. In addition to the growing workload, healthcare providers have psychological issues due to their worry of contracting an infection and spreading it to others. Healthcare personnel needs to be protected and given adequate working circumstances. Since protective gear including gloves that are secure, respiratory protection, and eyewear are crucial for the protection of medical professionals exposed to the virus, medical treatment should also be well arranged for. The fast-spreading COVID-19 epidemic has impacted numerous individuals throughout the globe. Considering the strong infectivity, governments issue advisories to stay at home or enact policies like lockdowns to prevent the spread of the illness. Arranging doctor scheduling is one of the crucial difficulties. As part of this study, create a doctor scheduling arrangements with a hospital in Turkey during the COVID-19 epidemic. In order to sustain activity in the new departments while lightening the load in the old departments, the hospital built three new COVID-19-related departments. To solve the arranging doctor scheduling issue, provide a Mixed Integer Programming (MIP) paradigm to turn the problem into a Decision Support System (DSS). The consequential schedules maintain healthcare delivery throughout all departments while distributing their effort evenly by reducing the risk of the doctors contracting the illness.

A Methodology for Calculating Inhalation Dose to Public Health Personnel Exposed to Material Resuspended from Evacuees Following the Detonation of a Fission Device.

Following a nuclear fission event, there likely would be a large number of contaminated persons who would seek assistance at community reception centers to be established outside the affected area. This paper provides a methodology for calculating inhalation doses to public health and other response personnel at such facilities who would be receiving and assisting potentially contaminated persons from whom particles can be resuspended. Three hypothetical facilities were considered: the Base Case is a rather small room with no forced air ventilation. The Preferred Case, which is more realistic, is a mid-sized room with an operating HVAC system with air being recirculated through a filter. The Gymnasium Case has only fresh air intake. Initial bounding calculations for the Base Case indicated the need for pre-screening of arrivals to avoid unacceptable doses to staff. The screening criterion selected was 1.67 × 10 6 Bq m -2 . Calculations are presented for radionuclide concentrations in air, dose to staff from inhalation, and how exposures and the resulting doses can be altered by air-turnover rates and the use of filters with varying efficiency. Doses are presented for various arrival times and for both plutonium- and uranium-fueled detonations. The highest calculated dose via inhalation with no respiratory protection was 0.23 mSv for the Base Case. The more important radionuclides contributing to dose with exposure starting at day D + 1 were 239 Np and 133 I. At day D + 30, 131 I and 140 Ba were the more important dosimetrically. The variable creating the highest uncertainty was the slough-off factor for resuspension of contamination from people arriving at the reception center.

Respiratory Protection: Lessons Learned from a Global Pandemic.

The COVID-19 pandemic exposed the limitations of global health systems' abilities to manage the rapid spread of a novel infectious disease, which was exacerbated by shortages of respiratory protective devices and other critical personal protective equipment (PPE). An advisory panel of experienced health-care professionals with backgrounds in Occupational and Environmental Health and Safety (OEHS), Infection Prevention, Nursing, and Clinical Application Specialists convened to discuss challenges and strategies associated with the selection and use of respiratory protective devices as experienced during the first year of the COVID-19 pandemic. This discussion led to the following recommendations: 1) the need for clear communication of alternative respiratory protection selection and use recommendations in accordance with US regulatory and agency guidance; 2) the need for collaboration between Infection Prevention, OEHS, clinical staff, supply chain/materials management, emergency preparedness, executive leadership, and finance; 3) the need for adequate stockpiling, inventory rotation, and diverse respiratory protection options to accommodate the majority of health-care workers; 4) the need for efficient and innovative strategies to communicate evolving regulatory, agency, and facility recommendations and to deliver appropriate training on respiratory protection; and 5) the need for additional research on respiratory protection use - involving filtering facepiece respirators (FFRs) as well as other respirator types designed to be reused - to balance infection prevention best practices with a sustainable process. In conclusion, these considerations may offer guidance and identify areas for research on preparedness, communication, education, and training to enhance the preparation of health-care facilities including community-based health-care organizations for unexpected public health events.

Bagasse dust exposure and chronic respiratory symptoms among workers in the Metehara and Wonji sugar factories in Ethiopia: a longitudinal study design

BackgroundEthiopia’s sugar factories are growing by creating job opportunities for thousands of workers with varying educational, professional and socioeconomic backgrounds. These sugar factories are a source of several hazards that...

Construction of Half Masks for the Respiratory Tract Protection and the Speech Intelligibility Assessed from the Measured Suppression of Sound

Half masks (a.k.a. filtering facepieces, FFP) are personal protective equipment against dust in a work environment. Their filtration efficiency is legally regulated. Occupational safety and health services have not paid enough attention to speech disruption caused by FFPs, even though the latter could impair verbal communication and result in discomfort or increased risk of accidents. This study deals with the objective differences in speech suppression between masks of various construction belonging to the same filtration class, FFP2, and equipped with exhalation valves. We applied an objective method of white noise attenuation, suggested in our previous work. Its uniqueness lies in the fact that the acoustic apparati are applied in the whole procedure, and no human speakers/listeners participation is required. We compared seven types of masks: three moulded, one moulded with folded elements, two folded horizontally, and one vertically. We determined attenuation caused by the masks in 1/3 octave-wide bands with centre frequency from 100 Hz to 20 kHz. All the studied FFPs attenuated sound waves in a frequency range responsible for 80–90% of the perceived speech intelligibility. The attenuations of moulded masks were ca. 3 dB higher in 1–16 kHz bands than those of folded ones. The moulded mask with foldable parts for better fitting the face suppressed the high-pitch tones considerably more than the other masks. These observations were confirmed quantitatively by the cluster analysis based on the Euclidean distances between the acoustic spectra.

Clinical Issues - August 2023.

Respiratory protection against surgical smoke from liver tissue Key words: surgical N95 respirator, surgical smoke, liver tissue, fine and ultrafine particles, particulate matter concentrations. Local exhaust ventilation and surgical smoke safety Key words: local exhaust ventilation (LEV), surgical smoke evacuation, medical-surgical suction, hierarchy of controls, engineering control. Location of endoscopy storage cabinets Key words: endoscope; sterile storage; contamination; environmental conditions; heating, ventilation, and air-conditioning (HVAC) design parameters. Sterility of ultrasound transmission gel Key words: sterile gel, nonsterile gel, multidose container, ultrasound, outbreaks.

Evaluation of health worker acceptance and tolerance of respirators in clinical practice—An Australian perspective

One of the main infection prevention and control measures introduced during the COVID-19 pandemic was the focused application of respiratory protection to ensure health worker safety and the effective use of personal protective equipment. However, user acceptance of these strategies is paramount in sustainable compliance. This study explores various aspects of respirator use and provides recommendations to improve and maximize health worker safety. The aim of this study was to understand the relationship between respirator (P2/N95) comfort and user experience towardrespiratory protection. The aim of this study was to understand the relationship between respirator (P2/N95) comfort and user experience towardrespiratory protection. The nonexperimental cross-sectional design study was conducted in New South Wales, Australia between November and December 2022 using an anonymous self-administered online questionnaire in Microsoft Forms. Of 2,514 respondents, 65% reported to have used a respirator every working day with only a few using a respirator once weekly or less (9%). Almost all respondents had completed at least one quantitative fit test (96%) prior to the survey. Fifty-nine percent reported to have experienced discomfort from wearing a respirator and the most reported adverse effect was difficulty communicating (64%), followed by skin irritation or acne (62%) and headache (56%). Despite somewhat less favorable ratings on comfort and communication, health workers are in favor of respiratory protection. However, a focus on tolerance of respirators and strategies to address adverse effects from prolonged respirator use must be considered when implementing policies and procedures. Moreover, resources must be allocated to improve the design, breathability, and sustainability of a respirator along with education and training on how to use respiratory protection safely and effectively.

Self-reported respiratory health symptoms and respiratory protection behaviors of young adult hog producers in the United States.

In this study, we evaluated self-reported respiratory symptoms during agricultural work, respiratory protection use and experience, and perceived value of receiving respirators using Gear Up for Ag Health and Safety Program™ pre- and post-surveys from 703 to 212 young adult hog producers in the United States. To our knowledge, this is one of the most extensive survey data sets on self-reported respiratory symptoms and respiratory protection behaviors of collegiate-aged young adults working in USlivestock production. About one-third (37%) of young adult hog producers stated that they have experienced cough, shortness of breath, fever, and chills after working in dusty areas on the farm. Most (76.2%) stated that they were already "always"or "sometimes"wearing filtering facepiece (N95-style) respirators, even before participating in an outreach program. About one-third (30%) reported experience wearing a cartridge-style respirator but only 5% reported having been fit-tested for a respirator. Young adult male producers were significantly more likely to report use of both respirator types when compared to females, both before and after the program. Male producers were also more likely than females to engage in high-risk farm tasks where respirators are recommended, such as cleaning out grain bins and mixing or grinding feed. Following an educational program, males and females reported using the respirators that they received at similar rates, and 20% of overall participants purchased additional respiratory protection. The study found that young adult hog producers in postsecondary education are already wearing respirators with some frequency and at rates higher than previously reported by agricultural workers. More research is needed to make effective task-based respirator-use recommendations and investigate some significant gender differences among young adult hog producers observed in this study.