Use Of Respiratory Protective Devices Research Articles

Prevalence of chronic respiratory symptoms and associated factors among woodwork workers in Bahir Dar City, Ethiopia; a comparative cross-sectional study

BackgroundExposure to wood dust can cause respiratory symptoms, like cough, phlegm, breathlessness, and chest pain, reduce lung function.ObjectiveThe objective of the study was to assess the prevalence of respiratory symptoms and associated factors among woodwork workers in Bahir-Dar city, Ethiopia.MethodsA comparative cross-sectional study was employed among 229 exposed and 228 unexposed groups. Participants for the study were selected using simple random sampling technique. The chronic respiratory symptoms were assessed using a questionnaire adopted from the American Thoracic Society. The data was entered using Epi-Data version 4.6 and export to SPSS version 22 for analysis. Poisson regression, Multivariate linear regression and multivariable logistic regression analysis were used to identify factors associated with woodworkers, general population and in pooled analysis.ResultThe prevalence of having at least one chronic respiratory symptom was higher among exposed group (59.4%) than unexposed group (18.0%) with PR = 3.03(95%CI: 2.45, 4.45). In woodworker; Not taking health and safety training(5.15,95%(CI:1.93–13.76),primary educational(3.85,95%,CI:(1.1,13.47), not using Mask(6.38, 95%CI:(2.69–15.76) & number of families(3.05,95%,CI:1.04–9.028), In general population; Number of family members(2.75, 95%CI:1.1–7.19)& lower monthly income (3.3, 95%CI: (1.49–7.4), and In pooled analysis; wood dust exposure status 14.36 95%, CI:(7.6–27.00),primary education(2.93,95%CI:1.24–6.92), number of families(3.46,95%CI:1.8–6.64), lower monthly income(2.13,95%CI:1.19–3.81), & smoking (6.65, 95%CI:1.19–36.9) were associated with respiratory symptom.ConclusionPrevalence of respiratory symptoms was higher among exposed group than unexposed group. Reduced wood dust exposure status, Provision of occupational safety and health training, use of respiratory protective devices is recommended to reduce respiratory symptoms among woodwork workers.

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.

Evaluation of the Microbiological Effectiveness of Three Accessible Mask Decontamination Methods and Their Impact on Filtration, Air Permeability and Physicochemical Properties.

The need to secure public health and mitigate the environmental impact associated with the massified use of respiratory protective devices (RPD) has been raising awareness for the safe reuse of decontaminated masks by individuals and organizations. Among the decontamination treatments proposed, in this work, three methods with the potential to be adopted by households and organizations of different sizes were analysed: contact with nebulized hydrogen peroxide (H2O2); immersion in commercial bleach (NaClO) (sodium hypochlorite, 0.1% p/v); and contact with steam in microwave steam-sanitizing bags (steam bag). Their decontamination effectiveness was assessed using reference microorganisms following international standards (issued by ISO and FDA). Furthermore, the impact on filtration efficiency, air permeability and several physicochemical and structural characteristics of the masks, were evaluated for untreated masks and after 1, 5 and 10 cycles of treatment. Three types of RPD were analysed: surgical, KN95, and cloth masks. Results demonstrated that the H2O2 protocol sterilized KN95 and surgical masks (reduction of >6 log10 CFUs) and disinfected cloth masks (reduction of >3 log10 CFUs). The NaClO protocol sterilized surgical masks, and disinfected KN95 and cloth masks. Steam bags sterilized KN95 and disinfected surgical and cloth masks. No relevant impact was observed on filtration efficiency.

Applying the CDC Science Impact Framework to the results of the National Institute for Occupational Safety and Health and the Bureau of Labor Statistics 2001 survey of respirator use and practices

During 2001–2002, the National Institute for Occupational Safety and Health (NIOSH), at the United States Centers for Disease Control and Prevention, collaborated with the Bureau of Labor Statistics (BLS) at the United States Department of Labor to conduct a voluntary survey of U.S. employers regarding the use of respiratory protective devices. In 2003, the survey results were jointly published by NIOSH and BLS. This study highlights and evaluates the scientific impact of the 2001–2002 survey by using the Science Impact Framework which provides a historical tracking method with five domains of influence. The authors conducted interviews with original project management as well as a thorough document review and qualitative content analysis of published papers, books, presentations, and other relevant print media. A semi-structured and cross-vetted coding was applied across the five domains: Disseminating Science, Creating Awareness, Catalyzing Action, Effecting Change, and Shaping the Future. The 2001–2002 survey findings greatly enhanced understanding and awareness of respirator use in occupational settings within the United States. It also led to similar surveys in other countries, regulatory initiatives by the Occupational Safety and Health Administration and Mine Safety and Health Administration, and ultimately to a renewed partnership between NIOSH and BLS to collect contemporary estimates of respirator use in the workplace within the United States.

Viscoelastic Polyurethane Foams with Reduced Flammability and Cytotoxicity.

Consistent and proper use of respiratory protective devices (RPD) is one of the essential actions that can be taken to reduce the risk of exposure to airborne hazards, i.e., biological and nonbiological aerosols, vapours, and gases. Proper fit of the facepiece and comfort properties of RPDs play a crucial role in effective protection and acceptance of RPDs by workers. The objective of the present paper was to develop viscoelastic polyurethane foams for use in RPD seals characterised by proper elasticity, allowing for the enhancement of the device fit to the face and the capability of removing moisture from the skin in order to improve the comfort of RPD use. Moreover, it was pivotal to ensure the non-flammability of the foams, as well as a simultaneous reduction in their cytotoxicity. The obtained foams were characterised using scanning electron microscopy, infrared spectroscopy, thermogravimetry, and differential scanning calorimetry. Measurements also involved gel fraction, apparent density, compression set, rebound resilience, wettability, flammability, and cytotoxicity. The results are discussed in the context of the impact of modifications to the foam formulation (i.e., flame-retardant type and content) on the desired foam properties. The test results set directions for future works aimed to develop viscoelastic polyurethane foams that could be applied in the design of respiratory protective devices.

Use of Respiratory Protection Devices by Medical Students during the COVID-19 Pandemic.

The use of face masks has assumed a leading spot among nonspecific prevention measures during the coronavirus pandemic. The effectiveness of this protective measure depends on the specifics of individual use. The purpose of our study was to analyze the use of respiratory protective equipment (RPE) by medical students during the COVID-19 pandemic. The evaluation of face mask use was based on the results of a survey of medical students at Sechenov University. There were 988 participants in the study: 97.5% used RPE during the pandemic, 89.1% used disposable medical and hygienic face masks, 27.4% used reusable cloth face masks, and 13.2% used respirators. The majority of respondents (75.2%) were found to wear face masks correctly. However, 17.0% of the respondents were found to cover only their mouths with a face mask, while 7.8% reported often shifting their face mask under the chin due to perceived discomfort. Only 25.1% of respondents changed their disposable face mask after 2–3 h of wearing, while 13.0% decontaminated and used it several times. Most cloth face mask users (93.7%) decontaminated their marks, but only 55.7% of respondents did so daily. Face masks were most often worn in medical organizations (91.5%), and 1.4% of respondents did not use respiratory protection anywhere. In conclusion, we consider it necessary to introduce a special module on nonspecific prevention in the discipline of hygiene.

Selection and Use of Respiratory Protection by Healthcare Workers to Protect from Infectious Diseases in Hospital Settings.

Infection control policies and guidelines recommend using facemasks and respirators to protect healthcare workers (HCWs) from respiratory infections. Common types of respirators used in healthcare settings are filtering facepiece respirators (FFRs) and powered air-purifying respirators (PAPRs). Aims of this study were to examine the current attitudes and practices of HCWs regarding the selection and use of respiratory protection and determine the acceptability of a novel PAPR. In-depth interviews were undertaken with 20 HCWs from a large tertiary hospital in Sydney, Australia. Participants were fit tested with a lightweight tight-fitting half-facepiece PAPR (CleanSpace2™ Power Unit, PAF-0034, by CleanSpace Technology®) using the TSI™ Portacount quantitative fit test method. Interview results showed that HCWs had a limited role in the selection and use of facemasks and respirators and had been using the devices provided by the hospital. The majority of subjects had no knowledge of hospital policy for the use of facemasks and respirators, had not been trained on the use of respirators, and had not been fit tested previously. Compliance with the use of facemasks and respirators was perceived as being low and facemasks and respirators were typically used only for short periods of time.All 20 participants were successfully fit tested to the CleanSpace2™ PAPR (overall geometric mean fit factor-6768). According to the exit surveys, CleanSpace2™ PAPRs were easy to don (14/20) and doff (15/20) and comfortable to wear (14/20). Most participants believed that PAPRs provide higher protection, comfort and reusability over N95 FFR and can be used during pandemics and other high-risk situations. HCWs should be aware of infection control policies and training should be provided on the correct use of respiratory protective devices. PAPRs can be used in hospital settings to protect HCWs from certain highly infectious and emerging pathogens, however, HCWs require adequate training on storage, use, and cleaning of PAPRs.

A qualitative study on barriers for the use of respiratory protective devices among rice mill workers in Ampara District, Sri Lanka

Introduction: Rice milling often carried out in the informal work sector generates paddy dust which is a hazard to the respiratory health of mill workers. Sri Lankan rice mill workers have shown reluctance in using respiratory protective apparatus during rice milling. Objectives: To describe the barriers for the use of respiratory protective devices during rice milling Methods: A qualitative study was conducted in the divisions of Ampara and Uhana in Ampara District in Sri Lanka during February 2016. Twenty-two in-depth interviews were conducted among rice mill workers, health professionals and government officers related to rice milling industry. Data were analysed using content analysis method. Results: The rice mill workers’ non-use of respiratory protective methods was mainly due to their negligence in personal respiratory health care and lack of support from the employer, health care institutes and other related institutes. Low level of comprehension of workers and less manpower in health care and other institutions were other contributing factors. Conclusions: Low priority given for respiratory health care by the workers, poor work environment and less support from the mill owner and relevant government authorities have resulted in non-use of respiratory protective devices among rice mill workers. Improving unhealthy work behaviour such as non-use of respiratory protective devices of the informal work sector is recommended using industry-based health education programs.

Impact of wearing a surgical mask on respiratory function in view of a widespread use during COVID-19 outbreak. A case-series study.

Background:Because of the COVID-19 outbreak, the widespread use of Respiratory Protective Devices (RPD) is recommended to prevent the spread of infection. This recommendation involves not only healthcare workers but other category of workers and the general population as well, in public places, especially where social distancing is difficult to maintain. The use of facemasks should not cause physical impairment to individuals, especially for people suffering from lung and heart diseases.Objectives:To evaluate the impact of RPDs on the respiratory function in healthy and asthmatic subjects, in order to identify the fitness for use mainly, but not only for, occupational purposes during COVID-19 outbreak.Methods:Ten individuals were included, three of which affected by asthma and three current smokers. A Respiratory Functional Test (RFT) was performed at three times: at the beginning of the work shift 1) without wearing and 2) wearing surgical masks, and 3) after 4 hours of usual working activities wearing the masks. Arterial Blood Gas (ABG) samples were also tested before the first test and the third test.Results:Observed RFTs and ABG parameters did not suffer significant variations, but for Maximal Voluntary Ventilation (P=0.002). Data on asthmatic subjects and smokers were comparable to healthy subjects.Discussion:Our results suggest that wearing a surgical mask does not produce significant respiratory impairment in healthy subjects nor in subjects with asthma. Four hours of continuing mask-wearing do not cause a reduction in breathing parameters. Fitness for use in subjects with more severe conditions has to be evaluated individually. Our adapted technique for RFTs could be adopted for the individual RPDs fitness evaluation.

Assessment of occupational exposure to asbestos fibers: Contribution of analytical transmission electron microscopy analysis and comparison with phase-contrast microscopy

ABSTRACTFrom November 2009 to October 2010, the French general directorate for labor organized a large field-study using analytical transmission electron microscopy (ATEM) to characterize occupational exposure to asbestos fibers during work on asbestos containing materials (ACM). The primary objective of this study was to establish a method and to validate the feasibility of using ATEM for the analysis of airborne asbestos of individual filters sampled in various occupational environments. For each sampling event, ATEM data were compared to those obtained by phase-contrast optical microscopy (PCOM), the WHO-recommended reference technique. A total of 265 results were obtained from 29 construction sites where workers were in contact with ACM. Data were sorted depending on the combination of the ACM type and the removal technique. For each “ACM-removal technique” combination, ATEM data were used to compute statistical indicators on short, fine and WHO asbestos fibers. Moreover, exposure was assessed taking into account the use of respiratory protective devices (RPD). As in previous studies, no simple relationship was found between results by PCOM and ATEM counting methods. Some ACM, such as asbestos-containing plasters, generated very high dust levels, and some techniques generated considerable levels of dust whatever the ACM treated. On the basis of these observations, recommendations were made to measure and control the occupational exposure limit. General prevention measures to be taken during work with ACM are also suggested. Finally, it is necessary to continue acquiring knowledge, in particular regarding RPD and the dust levels measured by ATEM for the activities not evaluated during this study.

Biomonitoring for Exposure Assessment to Styrene in the Fibreglass Reinforced Plastic Industry: Determinants and Interferents.

Fifty-eight workers exposed to styrene were monitored in four fibreglass reinforced plastic industries of Central Italy. The aim of the study was to explore the factors that can influence the levels of styrene exposure biomarkers of the workers and the aspects that might interfere with the exposure assessment measures, such as the co-exposure to acetone. Personal monitoring of professional exposure to airborne styrene and acetone was carried out by Radiello samplers and GC/MS analysis. Biological monitoring was performed by the determination of urinary metabolites, mandelic (MA), and phenylglyoxylic (PGA) acids with HPLC/MS/MS and unmetabolized styrene in saliva and venous blood by HS/GC/MS. The median values of the four sites ranged between 24.1 to 94.0mg m(-3) and 7.3 to 331.1mg g(-1) creatinine for airborne styrene and MA + PGA, respectively. A good linear correlation was found between styrene in air and its urinary metabolites (r = 0.854). The median value for airborne styrene was found to exceed the (Threshold Limit Value - Time Weighted Average) of 85 mg m(-3) in one site for all the workers and in two if only moulders are considered. The multiple linear regression model showed that the determinants of urinary MA + PGA excretion were the type of process, workers' tasks, level of acetone co-exposure, and the use of respiratory protection devices. Data show that the simultaneous exposure to acetone modify the styrene metabolism with a reduction in the levels of (MA + PGA) excreted. A significant linear log-correlation was found between salivary levels of styrene and blood concentration (r = 0.746) sampled at the same t x time.

Clinician Beliefs and Attitudes Regarding Use of Respiratory Protective Devices and Surgical Masks for Influenza.

While influenza transmission is thought to occur primarily by droplet spread, the role of airborne spread remains uncertain. Understanding the beliefs and attitudes of infectious disease physicians regarding influenza transmission and respiratory and barrier protection preferences can provide insights into workplace decisions regarding respiratory protection planning. Physicians participating in the Infectious Diseases Society of America's Emerging Infections Network were queried in November 2013 to determine beliefs and attitudes on influenza transmission. A subset of physicians involved in their facility's respiratory protection decision making were queried about respirator and surgical mask choices under various pandemic scenarios; availability of, and challenges associated with, respirators in their facility; and protective strategies during disposable N95 shortages. The majority of 686 respondents (98%) believed influenza transmission occurs frequently or occasionally via droplets; 44% of respondents believed transmission occurs via small particles frequently (12%) or occasionally (32%). Among the subset of respondents involved in respiratory protection planning at their facility, over 90% preferred surgical masks during provision of non-aerosol-generating patient care for seasonal influenza. However, for the same type of care during an influenza pandemic, two-thirds of respondents opted for disposable N95 filtering facepiece respirators. In settings where filtering facepiece (disposable) N95 respirators were in short supply, preferred conservation strategies included extended use and reuse of disposable N95s. Use of reusable (elastomeric facepiece) respirator types was viewed less favorably. While respondents identified droplets as the primary mode of influenza transmission, during a high-severity pandemic scenario there was increased support for devices that reduced aerosol-based transmission. Use of potentially less familiar respirator types may partially relieve shortages of disposable N95s but also may require significant education efforts so that clinicians are aware of the characteristics of alternative personal protective equipment.

Social Marketing Campaign Promoting the Use of Respiratory Protection Devices Among Farmers

ABSTRACTThis article describes the formal use of marketing concepts in a systematic approach to influence farmers to voluntarily increase respiratory protective device (RPD) use. The planning process for the project incorporated six key decision or action points, each informed by formative research or health behavior theory. The planning process included developing behavior change strategies based on a 4P model (product, price, place, and promotion). The resulting campaign elements included print and e-mail messages that leveraged motivators related to family and health in order to increase farmers’ knowledge about the risks of exposure to dusty environments, four instructional videos related to the primary barriers identified in using RPDs, and a brightly colored storage bag to address barriers to using RPDs related to mask storage. Campaign implementation included a series of e-mails using a bulk e-mail subscription service, use of social media in the form of posting instructional videos on a YouTube channel, and in-person interactions with members of the target audience at farm shows throughout the Central States Center for Agricultural Safety and Health seven-state region. Evaluation of the e-mail campaigns indicated increased knowledge about RPD use and intent to use RPDs in dusty conditions. YouTube analytic data indicated continuing exposure of the instructional videos beyond the life of the campaign. The project demonstrates the efficacy of a planning process that incorporates formative research and clear decision points throughout. This process could be used to plan health behavior change interventions to address other agriculture-related health and safety issues.

The penetration of respiratory protective devices by respirable solid particles

In certain industrial settings, for example, mining and quarrying, people must work in atmospheres containing large amounts of dust. This increases their chances of developing pneumoconiosis in some form or another. Even after taking all possible preventive measures against lung disease, the Spanish National Institute of Safety and Hygiene at Work still recommends the use of respiratory protective devices (RPDs). Unfortunately, some workers are reticent to use these devices since they cause them thermal stress and breathing difficulties etc. The selection of RPD should be made taking into account the job to be performed, the physical condition of the user, the degree of occupational exposure, and the concentration of the contaminant to be avoided (gases, vapours, particles, etc.) Given the concern expressed by worker representatives and safety delegates with respect to the use of the most appropriate device for different activities, several RPDs were tested experimentally, simulating extreme conditions to which workers might be exposed. Unexpected significant variation was seen between devices of the same category with respect to their penetration by dust particles.

Asthma and exposure to cleaning products - a European Academy of Allergy and Clinical Immunology task force consensus statement

Professional and domestic cleaning is associated with work-related asthma (WRA). This position paper reviews the literature linking exposure to cleaning products and the risk of asthma and focuses on prevention. Increased risk of asthma has been shown in many epidemiological and surveillance studies, and several case reports describe the relationship between exposure to one or more cleaning agents and WRA. Cleaning sprays, bleach, ammonia, disinfectants, mixing products, and specific job tasks have been identified as specific causes and/or triggers of asthma. Because research conclusions and policy suggestions have remained unheeded by manufactures, vendors, and commercial cleaning companies, it is time for a multifaceted intervention. Possible preventive measures encompass the following: substitution of cleaning sprays, bleach, and ammonia; minimizing the use of disinfectants; avoidance of mixing products; use of respiratory protective devices; and worker education. Moreover, we suggest the education of unions, consumer, and public interest groups to encourage safer products. In addition, information activities for the general population with the purpose of improving the knowledge of professional and domestic cleaners regarding risks and available preventive measures and to promote strict collaboration between scientific communities and safety and health agencies are urgently needed.

Carbon dioxide rebreathing in respiratory protective devices: influence of speech and work rate in full-face masks

Carbon dioxide (CO2) rebreathing has been recognised as a concern regarding respirator use and is related to symptoms of discomfort, fatigue, dizziness, headache, muscular weakness and drowsiness. Previous investigations are limited by small sample size and have not evaluated the relationship between CO2 inhalation and phonic respiration (breathing during speech) in respiratory protective devices (RPDs). A total of 40 workers trained in the use of RPDs performed a graded exercise test on a cycle ergonometer that increased in workload every 5 min. During the third minute of each stage, participants read aloud a prepared text. Measures of mixed expired CO2 (PECO2), mixed inspired CO2 (PICO2) and respiration were monitored. The results showed that phonic respiration and low work rates contributed to significantly higher levels of CO2 rebreathing. Aiming to reduce CO2 exposure may result in improved wear time of RPDs. It is recommended that these findings be incorporated in technical specifications regarding human factors for RPDs. Practitioner Summary: Carbon dioxide (CO2) rebreathing in respiratory protective devices (RPDs) has been highlighted as a key concern regarding respirator use. However, the problem is relatively under researched. This paper presents novel findings on the impact of phonic respiration (breathing during speech) and CO2 concentrations in RPDs.

Effectiveness of surgical masks against influenza bioaerosols

Most surgical masks are not certified for use as respiratory protective devices (RPDs). In the event of an influenza pandemic, logistical and practical implications such as storage and fit testing will restrict the use of RPDs to certain high-risk procedures that are likely to generate large amounts of infectious bioaerosols. Studies have shown that in such circumstances increased numbers of surgical masks are worn, but the protection afforded to the wearer by a surgical mask against infectious aerosols is not well understood. To develop and apply a method for assessing the protection afforded by surgical masks against a bioaerosol challenge. A dummy test head attached to a breathing simulator was used to test the performance of surgical masks against a viral challenge. Several designs of surgical masks commonly used in the UK healthcare sector were evaluated by measuring levels of inert particles and live aerosolised influenza virus in the air, from in front of and behind each mask. Live influenza virus was measurable from the air behind all surgical masks tested. The data indicate that a surgical mask will reduce exposure to aerosolised infectious influenza virus; reductions ranged from 1.1- to 55-fold (average 6-fold), depending on the design of the mask. We describe a workable method to evaluate the protective efficacy of surgical masks and RPDs against a relevant aerosolised biological challenge. The results demonstrated limitations of surgical masks in this context, although they are to some extent protective.

New Filtering Antimicrobial Nonwovens With Various Carriers for Biocides as Respiratory Protective Materials Against Bioaerosol

This study evaluated the bioactivity of polypropylene melt-blown filtering nonwovens used in respiratory protective devices (RPD) with a biocidal agent (alkylammonium microbiocides) on 2 mineral carriers. Two types of carriers were tested: a bentonite, with an aluminosilicate base, and a perlite, volcanic glass. High biostatic and biocidal effects of modified nonwovens with biocides were tested against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria. Nonwovens modified with a biocide on a bentonite carrier showed an opposite reaction to a biocide on a perlite. The research also showed that 10% concentration of a biocidal agent on a perlite carrier was sufficient to inhibit the growth of bacteria (100% reduction) placed in the structure of a filtering material during normal use of RPD. A comparison of the biological activity of 2 filtering materials, each containing 10% of a perlite and produced in a laboratory and industrial conditions, showed no statistically significant differences.

Factors influencing respirator use at work in respiratory patients

When engineering controls such as ventilation are not sufficient to prevent hazardous exposures in workplaces, respiratory protective devices (RPDs) may be provided to decrease workers' exposures. Often, workers do not use RPDs consistently when required. Our goal was to determine important factors associated with RPD usage in workers with respiratory disease exposed to airborne hazards at work. One hundred and twenty-nine respiratory clinic patients in jobs with self-identified hazardous airborne substances completed a questionnaire and their clinic files were reviewed. Statistical analysis using chi-squared test and binary logistical regression was done to identify associations with RPD usage. Forty-one per cent reported always wearing RPDs whenever a hazard was present; 33% never wore RPD. Compliance was highest among healthcare workers (72%) and lowest among workers in food and service industries (13 and 22%, respectively), P < 0.01. The compliance of co-workers, conveniently located RPDs, safety training discussing the use of RPDs, fit testing available at the workplace and age were positively associated with compliance (P < 0.05). Experiencing symptoms of shortness of breath and nasal stuffiness were negatively associated with compliance (P < 0.05). Addressing company factors and workers' symptoms apparently influencing compliance may optimize RPD usage.

Prevention of Occupational Asthma

Prevention of occupational asthma related to a work-sensitizing agent ideally would be achieved by avoidance of exposures that cause immunologic sensitization and subsequent asthma. There are a few examples in which a sensitizing agent has been removed from a work process and others in which exposure has been significantly changed or reduced with associated reduced rates of sensitization and disease. Additional measures include containment, use of robots, ventilation measures, exposure monitoring, and use of respiratory protective devices. Secondary prevention includes medical surveillance, which may involve periodic respiratory questionnaires, spirometry, and immunologic tests aiming to detect sensitization or disease early to allow intervention and improve outcomes. Education measures for workers to understand the meaning of work-related respiratory symptoms and appropriate workplace safety measures have not been formally evaluated but may also be expected to enhance protective measures and lead to earlier diagnosis. Tertiary prevention includes medical management and workers' compensation.