Health effects of filtering facepiece respirators: Systematic review of pulmonary and cardiovascular effects.

Filtering facepiece respirators (FFRs) were introduced to protect the wearer by removing small particles from inspired air. FFRs are now also used to reduce the spread of transmissible agents from the wearer and are worn outside traditional healthcare and other workplaces. The COVID-19 pandemic increased concerns about potential adverse effects on wearers. A PUBMED query retrieved articles through June 2022. Abstracts and selected full-text articles were systematically reviewed by the authors. This article focuses upon cardiopulmonary physiologic effects (e.g., ventilation, CO2 elimination, oxygen uptake, and respiratory control) with emphasis upon current and potential research methods as well as summarizing results. 1985 records were identified, of which only 26% were published before 2020. FFR effects on CO2 elimination appear more likely to be significant than effects on oxygenation or cardiovascular function. While FFRs appear well tolerated by healthy persons, more research is needed for those with pulmonary or cardiac disorders, and for children. Many traditional pulmonary exercise study methods require special care when applied to filtering facepiece respirators. Studying additional parameters may explain the paradox of many subjective discomfort reports despite very limited physiologic effects.

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.

Psycholinguistic Markers of COVID-19 Conspiracy Tweets and Predictors of Tweet Dissemination.

The adoption of conspiracy theories about COVID-19 has been fairly widespread among the general public and associated with the rejection of self-protective behaviors. Despite their significance, however, a gap remains in our understanding of the underlying characteristics of messages used to disseminate COVID-19 conspiracies. We used the construct of resonance as a framework to examine a sample of more than 1.8 million posts to Twitter about COVID-19 made between April and June 2020. Our analyses focused on the psycholinguistic properties that distinguish conspiracy theory tweets from other COVID-19 topics and predict their spread. COVID-19 conspiracy tweets were distinct and most likely to resonate when they provided explanations and expressed negative emotions. The results highlight the sensemaking functions served by conspiracy tweets in response to the profound upheaval caused by the pandemic.

Exposure frequency, intensity, and duration: What we know about work-related asthma risks for healthcare workers from cleaning and disinfection.

The objective of this review was to scope the current evidence base related to three exposure assessment concepts: frequency, intensity, and duration (latency) for cleaning and disinfection exposures in healthcare and subsequent work-related asthma risks. A search strategy was developed addressing intersections of four main concepts: (1) work-related asthma; (2) occupation (healthcare workers/nurses); (3) cleaning and disinfection; and (4) exposure. Three databases were searched: Embase, PubMed, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) database. Data were extracted related to three main components of risk assessment: (1) exposure frequency, (2) exposure intensity, and (3) exposure duration. Latency data were analyzed using an exponential distribution fit, and extracted concentration data were compared to occupational exposure limits. The final number of included sources from which data were extracted was 133. Latency periods for occupational asthma were exponentially distributed, with a mean waiting time (1/λ) of 4.55 years. No extracted concentration data were above OELs except for some formaldehyde and glutaraldehyde concentrations. Data from included sources also indicated some evidence for a dose-response relationship regarding increased frequency yielding increased risk, but this relationship is unclear due to potential confounders (differences in role/task and associated exposure) and the healthy worker effect. Data priority needs to include linking concentration data to health outcomes, as most current literature does not include both types of measurements in a single study, leading to uncertainty in dose-response relationships.

Respiratory protection for health care workers: A 2020 COVID-19 perspective.

As the US health care system began to respond to the coronavirus disease-2019 pandemic, demand for respiratory personal protective equipment (PPE) increased precipitously, as did the number of users. This commentary discusses ensuing deviations from accepted respiratory PPE program practices, which potentially increased risk to health care workers. Such lapses included omitting user training and fit testing, provision of unapproved devices, and application of devices in settings and ways for which they were not intended. The temporary compromise of professionally accepted standards due to exigencies must not become the new normal. Rather, the current attention to PPE should be leveraged to enhance practice, motivate vital research, and strengthen professional, governmental, and institutional capabilities to control health care worker exposures to infectious hazards.

Evaluation of a fitness intervention for new firefighters: injury reduction and economic benefits.

BACKGROUND: Firefighting is a hazardous profession and firefighters suffer workplace injury at a higher rate than most US workers. Decreased physical fitness is associated with injury in firefighters. A physical fitness intervention was implemented among Tucson Fire Department recruit firefighters with the goals of decreasing injury and compensation claims frequency and costs during the recruit academy, and over the subsequent probationary year. METHODS: Department injury records were analysed and described by body part, injury type and mechanism of injury. Injury and workers' compensation claims outcomes from the recruit academy initiation through the 12-month probationary period for the intervention recruit class were compared with controls from three historical classes. RESULTS: The majority of injuries were sprains and strains (65.4%), the most common mechanism of injury was acute overexertion (67.9%) and the lower extremity was the most commonly affected body region (61.7%). The intervention class experienced significantly fewer injuries overall and during the probationary year (p=0.009), filed fewer claims (p=0.028) and experienced claims cost savings of approximately US$33 000 (2013) from avoided injury and reduced claims costs. The estimated costs for programme implementation were $32 192 leading to a 1-year return on investment of 2.4%. CONCLUSIONS: We observed reductions in injury occurrence and compensation costs among Probationary Firefighter Fitness (PFF-Fit) programme participants compared with historical controls. The initiation of the PFF-Fit programme has demonstrated promise in reducing injury and claims costs; however, continued research is needed to better understand the programme's potential effectiveness with additional recruit classes and carryover effects into the recruit's career injury potential.

Predicting future protection of respirator users: Statistical approaches and practical implications.

The purpose of this article is to describe a statistical approach for predicting a respirator user's fit factor in the future based upon results from initial tests. A statistical prediction model was developed based upon joint distribution of multiple fit factor measurements over time obtained from linear mixed effect models. The model accounts for within-subject correlation as well as short-term (within one day) and longer-term variability. As an example of applying this approach, model parameters were estimated from a research study in which volunteers were trained by three different modalities to use one of two types of respirators. They underwent two quantitative fit tests at the initial session and two on the same day approximately six months later. The fitted models demonstrated correlation and gave the estimated distribution of future fit test results conditional on past results for an individual worker. This approach can be applied to establishing a criterion value for passing an initial fit test to provide reasonable likelihood that a worker will be adequately protected in the future; and to optimizing the repeat fit factor test intervals individually for each user for cost-effective testing.

Respiratory disability and impairment: what is new?

PURPOSE OF REVIEW: This review summarizes recent advances concerning respiratory impairment and disability. RECENT FINDINGS: The traditional impairment assessment approach, depending heavily on clinical pulmonary function testing to estimate the match between the patient's sustainable oxygen consumption and the workplace requirements, continues to be widely used. Recent work indicates the need to reassess underlying concepts for several reasons: The relationship between basic pulmonary function tests and sustainable oxygen consumption varies among patients and conditions. Studies of the respiratory demands of modern workplaces need to be updated. The concepts are less easily applied to asthma than other disorders. Research studies present differing definitions of 'disability', and therefore the methods of relating impairment (function loss) and disability require reassessment. Recent advances provide improved understanding of the large societal and personal impacts of respiratory impairment and disability. SUMMARY: Clinicians, policymakers, and researchers should carefully consider how well the current highly specified impairment rating systems can be improved for accuracy and relevance to current home and work activities. In addition to measuring 'impairment', clinicians should consider factors affecting how impairments lead to disability.

Potential role of infrared imaging for detecting facial seal leaks in filtering facepiece respirator users.

Infrared imaging (IRI) can detect airflow through and near respirator masks based upon temperature differences between ambient and exhaled air. This study investigated the potential usefulness of IRI for detecting leaks and providing insight into the sites and significance of leaks. Subjects (n = 165) used filtering facepiece N95 respirators (N95 FFR) in the course of a research study concerning training modalities. Short sequence video infrared images were obtained during use and with intentionally introduced facial seal leaks. Fit factor (FF) was measured with condensation nuclei count methods. IRI detected leaks were scored on a four-point scale and summarized as the Total Leak Score (TLS) over six coding regions and the presence or absence of a "Big Leak" (BL) in any location. A semi-automated interpretation algorithm was also developed. IRI detected leaks are particularly common in the nasal region, but these are of limited significance. IR imaging could effectively identify many large leaks. The TLS was related to FF. Although IRI scores were related to FF, the relationship is insufficiently close for IRI to substitute for quantitative fit-testing. Using FFRs infrared techniques have potential for identifying situations with very inadequate respiratory protection.

An official American Thoracic Society systematic review: Influence of psychosocial characteristics on workplace disability among workers with respiratory impairment.

RATIONALE: Psychosocial characteristics likely play an important role in the severity of workplace disability for workers with a respiratory impairment. OBJECTIVES: We performed a systematic review of the available literature to examine the impact of psychosocial characteristics on workplace disability among workers with a respiratory impairment. METHODS: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations, we searched Medline and other published and unpublished sources using the PubMed and Cochrane Central Register of Controlled Clinical Trials (CENTRAL) search engines from January 1, 1990 through March 8, 2013 for quantitative studies that examined the association of psychosocial characteristics with workplace disability among workers with a respiratory impairment. We also searched related citations and the bibliographies of selected studies and relevant review articles. One investigator abstracted data about study design and quality, psychosocial characteristics, and outcome measures. MEASUREMENTS AND MAIN RESULTS: Of 5,746 potentially relevant studies, 20 met eligibility criteria and were included. Studies reported heterogeneous outcomes among heterogeneous samples of workers that precluded a quantitative synthesis. In general, mental illness was associated with increased workplace disability among workers with respiratory impairments. Few studies adjusted for disease severity, so the independent association of psychosocial characteristics and workplace disability is unclear. Most studies were cross-sectional, so the direction of the association could not be determined. We found only one trial of targeted therapy for the psychosocial condition, which was not effective at reducing disability. CONCLUSIONS: Psychosocial characteristics likely influence workplace disability in workers with respiratory impairments. The impact of targeted therapies is unclear and warrants further study.

Persistence of respirator use learning.

Although retraining and repeat fit-testing are needed for respirator users, the optimal frequency is uncertain. The persistence of proper respirator donning/doffing techniques and changes in quantitative fit factor over 6 months after initial training were measured in this study. Initial training was designed for rapid rollout situations in which direct contact with well-trained occupational health professionals may be infeasible. Subjects (n = 175) were assigned randomly to use either a filtering facepiece N95 (FFR) or dual cartridge half facemask (HFM) respirator. Each was assigned randomly to one of three training methods-printed brochure, video, or computer-based training. Soon after initial training, quantitative fit and measures of proper technique were determined. These measurements were repeated 6 months later. In the six-month followup, subjects were randomized to receive either a brief reminder card or a placebo card. Total performance score, major errors, and quantitative fit all became significantly worse at 6 months. An individual's result soon after training was the most important predictor of performance 6 months later. There was a marginal not statistically significant tendency for those initially trained by video to have better protection 6 months later. The study suggests that persons who use respirators intermittently should be thoroughly retrained and reevaluated periodically. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: Additional statistical analyses.

MEDICAL EVALUATION FOR RESPIRATOR USE- UPDATED APPROACHES.

OBJECTIVE: Respirator medical evaluations are an important component of occupational health practice. Concepts and practices were established 25-50 years ago.METHODWe suggest analysis and discussion of three areas warranting update. RESULTS: a) Shifting from disease-based decisions to evaluating 12 specific domains- cardiopulmonary, sudden change in condition, thermal, work interference, exacerbating existing condition, donning/doffing, dermatologic, proper utilization, fit testing interference, cultural/religious, arms/legs, subjective responses. Two distinct evaluation processes are advised-"algorithmic" for the frequent straightforward evaluations and "specialist" for the more complex. b) Acknowledging the importance of subjective responses and clarifying the underlying causes - external stimulus, sensation, perception, interpretation, acceptability, and emotional response. c) Optimizing the organizational structures by explicitly defining the scope of evaluations, modifying the sequencing of assessment, and specifying qualifications of clinicians performing assessments. CONCLUSIONS: Reassessing respirator medical evaluation methods is needed.

Text and Audio Simplification: Human vs. ChatGPT.

Text and audio simplification to increase information comprehension are important in healthcare. With the introduction of ChatGPT, evaluation of its simplification performance is needed. We provide a systematic comparison of human and ChatGPT simplified texts using fourteen metrics indicative of text difficulty. We briefly introduce our online editor where these simplification tools, including ChatGPT, are available. We scored twelve corpora using our metrics: six text, one audio, and five ChatGPT simplified corpora (using five different prompts). We then compare these corpora with texts simplified and verified in a prior user study. Finally, a medical domain expert evaluated the user study texts and five, new ChatGPT simplified versions. We found that simple corpora show higher similarity with the human simplified texts. ChatGPT simplification moves metrics in the right direction. The medical domain expert's evaluation showed a preference for the ChatGPT style, but the text itself was rated lower for content retention.

Effects of Added Emphasis and Pause in Audio Delivery of Health Information.

Health literacy is crucial to supporting good health and is a major national goal. Audio delivery of information is becoming more popular for informing oneself. In this study, we evaluate the effect of audio enhancements in the form of information emphasis and pauses with health texts of varying difficulty and we measure health information comprehension and retention. We produced audio snippets from difficult and easy text and conducted the study on Amazon Mechanical Turk (AMT). Our findings suggest that emphasis matters for both information comprehension and retention. When there is no added pause, emphasizing significant information can lower the perceived difficulty for difficult and easy texts. Comprehension is higher (54%) with correctly placed emphasis for the difficult texts compared to not adding emphasis (50%). Adding a pause lowers perceived difficulty and can improve retention but adversely affects information comprehension.

Component analysis of respirator user training.

Respirators must be properly used to be effective. In an experimental protocol, 145 subjects were trained and then observed donning and doffing respirators. Filtering facepiece and dual cartridge half face mask types were studied. Subjects were then tested for knowledge and for proper performance using video recording analysis. Knowledge tests showed adequate learning, but performance was often poor. Inspection, strap tension (half mask), seal checking, and avoiding mask contact during doffing were particularly problematic. Mask positioning was generally well done. Correlation between knowledge and performance for specific items was generally poor, although there was a weak correlation between overall knowledge and overall performance (rho = 0.32) for the half mask users. Actual unprompted performance as well as knowledge and fit-testing should be assessed for user certification. Respirator design approval should consider users' ability to learn proper technique.