Comparison of ACGIH lifting threshold limit values to validated low back disorder lifting assessment methods outcomes.

BACKGROUND: Work-related low back pain (LBP) increases the workforce disability and healthcare costs. This study evaluated the LBD risk level associated with handling the ACGIH TLVs in lifting tasks corresponding to various horizontal and vertical zones. OBJECTIVE: The aim of this study was to compare the low-risk ACGIH TLV to risk outcomes from various validated lifting assessment methods, including the OSU LBD Risk Model, NIOSH Lifting Equation, and LiFFT. METHODS: Twenty-four subjects were recruited for this study to perform various lifting conditions. The various ergonomic assessment methods were then used to obtain the risk assessment outcomes. RESULTS: The selected assessment methods showed that the ACGIH-defined TLVs are associated with less than high-risk for LBD for all the assessed tasks. The findings showed a moderate agreement (Kendall's W = 0.477) among the various assessment methods risk outcomes. The highest correlation (ρ= 0.886) was observed between the NIOSH Lifting Equation and LiFFT methods risk assessment outcomes. CONCLUSION: The findings showed that ACGIH-defined TLVs possesses less than high-risk for LBD. The outcomes of the selected ergonomic assessment methods moderately agree to each other.

Measuring the benefits of occupational safety and health research with economic metrics: Insights from the National Institute for Occupational Safety and Health.

Measuring the ultimate impact of research on health and economic well-being has presented challenges that have rarely been surmounted, and research on preventing occupational injuries and illnesses is no exception. Nevertheless, there is an increasing need to demonstrate the value of publicly funded research. The National Institute for Occupational Safety and Health (NIOSH) recently contracted with the RAND Corporation to conduct six in-depth case studies that aimed to quantify the benefits of key NIOSH research efforts using economic metrics. These case studies focused on silica exposure in asphalt pavement milling, firefighter cancer risks, a multi-industry matching-grant program for purchase of safety equipment, personal coal dust monitors for coal miners, re-design of ambulance patient compartments for safety, and workplace amputation surveillance. In this article, we summarize what we learned about how measurement of research benefits may be pursued. We summarize the benefit measurement methods that were used and the results of these research efforts in terms of costs saved, injuries and illnesses prevented, and the statistical value of reductions in risk of death or illness. We then distill some observations about the characteristics of research efforts that make measurement of research benefits feasible and suggest steps that could make it feasible to apply the same methods more widely. We also outline key NIOSH activities that appear not to be amenable to benefit measurement but suggest potentials for progress toward at least partial or qualitative benefit assessment. Finally, we discuss implications of the benefit measurement case studies for strategic research planning.

Working: The Role of Occupational Epidemiology.

The coronavirus disease 2019 (COVID-19) pandemic has redemonstrated the importance of work as a determinant of health. During the pandemic, extant disparities were accentuated as the workforce was divided into the roughly 50% who could safely work from home and those who could not. With the spotlight on work, one might wonder where all the occupational epidemiologists have gone. To answer, we point to diminished research support and more limited workplace access that have led many epidemiologists to shift away from a focus on workers toward other vulnerable populations. Here we build on the renewed interest in work as a driver of health and inequality during the pandemic to highlight contributions of occupational epidemiology to public health. We consider: 1) etiological studies of chronic disease based on employment records to define cohorts and reconstruct long-term exposure; 2) studies of hypothetical interventions that are particularly appropriate for evaluating potential regulations to reduce workplace exposures; and 3) studies of disparities that take advantage of work as a potential source of social stratification and economic opportunity. As we have learned during the COVID-19 pandemic, workplaces can become venues for public health messaging and delivering interventions to enumerated populations of adults. By starting with COVID-19 prevention policies for the workplace, we have a chance to better protect public health.

Risk assessment of workers' exposure to BTEX and hazardous area classification at gasoline stations.

Vaporization of benzene, toluene, ethylbenzene, and xylene (BTEX) compounds pollutes the air and causes health hazards at gasoline stations. This study revealed the risk of BTEX exposure according to the hazardous area classification at gasoline stations. The risk assessment of gasoline workers from a representative group of 47 stations, which followed the United States Environmental Protection Agency-IRIS method of assessing BTEX exposure, was expressed as the hazard index (HI). A result of matrix multipliers of the hazardous exposure index and fire possibility from flammable gas classified hazardous area-I and area-II at the fuel dispensers. BTEX concentrations were actively sampled in ambient air and a flammable gas detector was used to measure the flammability level. Results showed that the BTEX concentrations from ambient air monitoring were in the range of 0.1-136.9, 8.1-406.0, 0.8-24.1 and 0.4-105.5 ppb for benzene, toluene, ethylbenzene, and xylene, respectively, which exceeded the NIOSH exposure limit of 100 ppb of benzene concentration. The risk assessment indicated that five stations reached an unacceptable risk of worker exposure to BTEX (HI>1), which correlated with the numbers of gasoline dispensers and daily gasoline sold. The risk matrix classified hazardous area-I at 4 meters and hazardous area-II at 4-8 meters in radius around the fuel dispensers. This study revealed the hazardous areas at gasoline stations and suggests that entrepreneurs must strictly control the safety operation practice of workers, install vapor recovery systems on dispenser nozzles to control BTEX vaporization and keep the hazardous areas clear of fire ignition sources within an eight-meter radius of the dispensers.

Work-Related Risk Assessment According to the Revised NIOSH Lifting Equation: A Preliminary Study Using a Wearable Inertial Sensor and Machine Learning.

Many activities may elicit a biomechanical overload. Among these, lifting loads can cause work-related musculoskeletal disorders. Aspiring to improve risk prevention, the National Institute for Occupational Safety and Health (NIOSH) established a methodology for assessing lifting actions by means of a quantitative method based on intensity, duration, frequency and other geometrical characteristics of lifting. In this paper, we explored the machine learning (ML) feasibility to classify biomechanical risk according to the revised NIOSH lifting equation. Acceleration and angular velocity signals were collected using a wearable sensor during lifting tasks performed by seven subjects and further segmented to extract time-domain features: root mean square, minimum, maximum and standard deviation. The features were fed to several ML algorithms. Interesting results were obtained in terms of evaluation metrics for a binary risk/no-risk classification; specifically, the tree-based algorithms reached accuracies greater than 90% and Area under the Receiver operating curve characteristics curves greater than 0.9. In conclusion, this study indicates the proposed combination of features and algorithms represents a valuable approach to automatically classify work activities in two NIOSH risk groups. These data confirm the potential of this methodology to assess the biomechanical risk to which subjects are exposed during their work activity.

Comparative analyses of workers' compensation claims of injury among temporary and permanent employed workers in Ohio.

BACKGROUND: A small but increasing number of studies have examined the risk of injury among temporary workers compared to that among workers in permanent employer arrangements. The purpose of this study was to conduct a comparative analysis of injury risk among temporary and permanent employer workers using a large dataset of workers' compensation (WC) claims of injury. METHODS: Over 1.3 million accepted WC claims in Ohio during the years 2001 to 2013 were analyzed, including 45 046 claims from workers employed by temporary services agencies. General descriptive statistics, injury rates and rate ratios (temporary to permanent workers) were calculated by injury type and event, industry group, and industry manual classes. RESULTS: Injured temporary workers were younger and had less tenure compared to injured permanent workers. Temporary workers had higher injury rates, and lower lost-time and medical costs. Differences in injury rates between temporary and permanent workers varied by injury event, industry, and manual class. CONCLUSION: Temporary workers had higher overall injury rates than permanent workers, controlling for industry manual class. These differences were pronounced for certain industries and injury events. We were not able to control for age and tenure of the worker, so it is not clear how these factors affected observed results. These findings were mostly similar to those from other studies using WC data from the states of Washington and Illinois. Together, these studies provide insights to improve injury prevention among temporary workers, however, additional research is still needed to improve safety and health programming for this group of workers.

Occupational health risk assessment of volatile organic compounds emitted from the coke production unit of a steel plant.

In this study, cancer and non-cancer risks of exposure to volatile organic compounds in the coke production unit of a steel plant were evaluated. To determine individual exposure to benzene, toluene, xylene and ethylbenzene, personal samples were taken from the breathing zone of workers according to National Institute for Occupational Safety and Health (NIOSH) method 1501. Cancer and non-cancer risk assessment was performed, using US Environmental Protection Agency (US EPA) methods. Samples analysis showed that the concentration of benzene in the energy and biochemistry and the benzol refinement sections was higher than occupational exposure limits. The cancer risk for benzene in all sections was significantly higher than allowable limit; the non-cancer risk for benzene in all sections and toluene in the benzol refinement section was also higher than 1.0. In conclusion, the current control measures are not sufficient and should be improved for efficient control of occupational exposures.

From plan to action: Adapting evaluation to serve the developmental needs of a newly-funded multidisciplinary research center.

The Southeastern Coastal Center for Agricultural Health and Safety (SCCAHS) is one of many newly-funded federal research centers, housing five multidisciplinary research projects and seven pilot projects, and serving a multi-state region. In the early stages of such a complex project, with multiple teams separated by geography and disciplines, the evaluation program has been integral in connecting internal and external stakeholders at the center and project levels. We used a developmental evaluation (DE) framework to respond to the complex political environment surrounding agricultural health and safety in the southeast; to engage external stakeholders in guiding the center's research and outreach trajectories; to support center research teams in a co-creation process to develop logic models and tailored indicators; and to provide timely and feedback within the center to address communications gaps identified by the evaluation program. By using DE principles to shape monitoring and evaluation approaches, our evaluation program has adapted to the dynamic circumstances presented as our center's progress has been translated from a plan in a grant proposal to implementation.

Outcomes of a Heat Stress Awareness Program on Heat-Related Illness in Municipal Outdoor Workers.

INTRODUCTION: Heat stress is an occupational hazard. Exposed workers may suffer heat-related illness, disease exacerbation, increased injuries, and reduced productivity. Response strategies include mitigation policies and preparedness. METHODS: Frequency of heat-related illness and workers' compensation costs before and after implementation of a voluntary Heat Stress Awareness Program were evaluated retrospectively in outdoor workers from 2009 to 2017. The program consisted of training, acclimatization, and medical monitoring as outlined in NIOSH's Criteria for a Recommended Standard: Occupational Exposure to Heat and Hot Environments. RESULTS: Of the 604 workers assessed, those with two or more risk factors reported a heat-related illness at greater frequency, which decreased after program implementation. Median workers' compensation costs decreased by 50%. DISCUSSION: Heat-related illness prevention programs can be effective in reducing the frequency and severity of these occupational injuries as well as associated costs.

Highlights from occupational safety and health continuing education needs assessment.

BACKGROUND: There is a lack of trained Occupational Safety and Health (OSH) professionals able to meet the current and future demand for such expertize in the United States. Many OSH professionals are required to perform duties, which are outside of their primary area of expertize; thus, expansion of continuing education (CE) may be necessary to properly train individuals for new OSH responsibilities. METHODS: The National Institute for Occupational Safety and Health-funded Education and Research Centers collectively developed and distributed an internet-based survey to gauge the CE needs and interests of the OSH workforce. RESULTS: A total of 2064 responses were received. The most common primary professions represented were safety (28%), occupational health nursing (18%), and industrial hygiene (12%). The majority of respondents (61%) reported that they perform work activities outside of those associated with their primary OSH profession. The CE offerings with the highest interest among respondents were related to safety. Other courses with high levels of interest included topics such as legal issues in OSH (88%), compliance (88%), risk management (85%), OSH management (83%), risk communication (83%), and communication in accident prevention (81%). Health and safety leadership (82%), health and safety culture (78%) and total worker health (74%) were also significant interests. CONCLUSIONS: It is important to be responsive to the evolving needs of the OS&H community. Developing relevant courses will help ensure that OS&H professionals have access to the training they need to perform essential job functions and keep employees healthy and safe.

Assessment of respirator fit capability test criteria for full-facepiece air-purifying respirators.

An ASTM International subcommittee on Respiratory Protection, F23.65 is currently developing a consensus standard for assessing respirator fit capability (RFC) criteria of half-facepiece air-purifying particulate respirators. The objective of this study was to evaluate if the test methods being developed for half-facepiece respirators can reasonably be applied to nonpowered full-facepiece-air-purifying respirators (FF-APR). Benchmark RFC test data were collected for three families of FF-APRs (a one-size-only family, a two-size family, and a three-size family). All respirators were equipped with P100 class particulate filters. Respirators were outfitted with a sampling probe to collect an in-mask particle concentration sample in the breathing zone of the wearer. Each of the six respirator facepieces was tested on the National Institute for Occupational Safety and Health 25-subject Bivariate Panel. The RFC test assessed face seal leakage using a PortaCount fit test. Subjects followed the corresponding Occupational Safety and Health Administration-accepted fit test protocol. Two donnings per subject/respirator model combination were performed. The panel passing rate (PPR) (number or percentage of subjects in the panel achieving acceptable fit on at least one of two donnings) was determined for each respirator family at specified fit factor passing levels of 500, 1,000, and 2,000. As a reasonable expectation based on a previous analysis of alpha and beta fit test errors for various panel sizes, the selected PPR benchmark for our study was >75%. At the fit factor passing level of 500 obtained on at least one of two donnings, the PPRs for three-, two-, and one-size families were 100, 79, and 88%, respectively. As the fit factor passing criterion increased from 500 to 1,000 or 2,000, PPRs followed a decreasing trend. Each of the three tested families of FF-APRs are capable of fitting ≥75% of the intended user population at the 500 fit factor passing level obtained on at least one of two donnings. The methods presented here can be used as a reference for standards development organizations considering developing RFC test requirements.

Assessment and control of exposures to polymeric methylene diphenyl diisocyanate (pMDI) in spray polyurethane foam applicators.

In this work we characterize personal inhalation and dermal exposures to diphenyl methane diisocyanate (MDI) and other species in polymeric MDI (pMDI) formulations during spray polyurethane foam (SPF) insulation at 14 sites in New England. We further assess the adequacy of current workplace practices and exposure controls via comparative urinary biomonitoring of the corresponding methylene diphenyl diamine (MDA) pre- and post-shift. MDI and pMDI are potent dermal and respiratory sensitizers and asthmagens, strong irritants of the skin, eyes, and the respiratory tract, and may cause skin burns. This study is the first comprehensive report to-date on the work practices, inhalation and dermal exposures to isocyanates and effectiveness of existing controls during SPF applications. Breathing zone exposures to 4,4' MDI (n = 31; 24 sprayers, 7 helpers) ranged from 0.9 to 123.0 µg/m3 and had a geometric mean (GM) of 13.8 µg/m3 and geometric standard deviation (GSD) of 4.8. Stationary near field area samples (n = 15) were higher than personal exposures: GM, 40.9 (GSD, 3.9) µg/m3, range 1.4-240.8 µg/m3. Sixteen percent of personal air samples and 35% of area samples exceeded the National Institute for Occupational Health and Safety's (NIOSH) full shift recommended exposure limit (REL) of 50 µg/m3, assuming zero exposure for the unsampled time. 4,4' MDI load on the glove dosimeters had a GM of 11.4 (GSD 2.9) µg/glove pair/min, suggesting high potential for dermal exposures. Urinary MDA had a GM of 0.7 (GSD, 3.0) µmol MDA/mol creatinine (range, nd-14.5 µmol MDA/mol creatinine). Twenty-five % of urine samples exceeded the Health and Safety Executive (HSE) biological monitoring guidance value (BMGV) of 1 µmol MDA/mol creatinine. We further report on field observations regarding current exposure controls, discuss implications of these findings and opportunities for improving work practices to prevent isocyanate exposures during SPF insulation.

Total Worker Health® 2014⁻2018: The Novel Approach to Worker Safety, Health, and Well-Being Evolves.

Background: The objective of this article is to provide an overview of and update on the Office for Total Worker Health® (TWH) program of the Centers for Disease Control and Prevention's National Institute for Occupational Safety and Health (CDC/NIOSH). Methods: This article describes the evolution of the TWH program from 2014 to 2018 and future steps and directions. Results: The TWH framework is defined as policies, programs, and practices that integrate protection from work-related safety and health hazards with promotion of injury and illness prevention efforts to advance worker well-being. Conclusions: The CDC/NIOSH TWH program continues to evolve in order to respond to demands for research, practice, policy, and capacity building information and solutions to the safety, health, and well-being challenges that workers and their employers face.

Application of the 2015 proposed NIOSH vapor containment performance protocol for closed system transfer devices used during pharmacy compounding and administration of hazardous drugs.

PURPOSE: The National Institute for Occupational Safety and Health (NIOSH) released a proposed protocol in 2015 to evaluate the vapor containment abilities of closed system transfer device technologies in order to provide meaningful comparisons between products. This study assessed the vapor containment ability of closed system transfer devices when following the methodology as outlined by the 2015 NIOSH proposed protocol. METHODS: This study evaluated six closed system transfer device brands following the draft NIOSH vapor containment protocol. The testing evaluated each closed system transfer device brand during both compounding (Task 1) and administration (Task 2). Five pre-specified steps for each task were repeated for a total of four manipulations per device. The Thermo Scientific™ MIRAN SapphIRe XL Infrared Analyzer was used to detect isopropyl alcohol vapor levels after each step. RESULTS: For Task 1, two closed system transfer device products (PhaSeal™ and Equashield®) adequately contained the isopropyl alcohol vapor and passed the predefined testing criteria. The same two products, plus one additional product (ChemoLock™), contained the vapor for Task 2 manipulations. Based on the results of this study, only two out of the six closed system transfer device brands passed testing criteria for both tasks, functioning as truly closed systems. CONCLUSION: To improve employee safety in chemotherapy preparation, closed system transfer devices that demonstrate no leakage should be the preferred choices of healthcare systems. In this study, PhaSeal™ and Equashield® proved to be adequately closed in both Task 1 and Task 2, while ChemoLock™ proved to be closed in Task 2 but not in Task 1. All other products failed both tasks when measuring for isopropyl alcohol vapor release.

Improving the risk assessment capability of the revised NIOSH lifting equation by incorporating personal characteristics.

The impact of manual material handling such as lifting, lowering, pushing, pulling and awkward postures have been studied, and models using these external demands to assess risk of injury have been developed and employed by safety and health professionals. However, ergonomic models incorporating personal characteristics into a comprehensive model are lacking. This study explores the utility of adding personal characteristics such as the estimated L5/S1 Intervertebral Disc (IVD) cross-sectional area, age, gender and Body Mass Index to the Revised NIOSH Lifting Equation (RNLE) with the goal to improve risk assessment. A dataset with known RNLE Cumulative Lifting Indices (CLIs) and related health outcomes was used to evaluate the impact of personal characteristics on RNLE performance. The dataset included 29 cases and 101 controls selected from a cohort of 1022 subjects performing 667 jobs. RNLE risk assessment was improved by incorporation of personal characteristics. Adding gender and intervertebral disc size multipliers to the RNLE raised the odds ratio for a CLI of 3.0 from 6.71 (CI: 2.2-20.9) to 24.75 (CI: 2.8-215.4). Similarly, performance was either unchanged or improved when some existing multipliers were removed. The most promising RNLE change involved incorporation of a multiplier based on the estimated IVD cross-sectional area (CSA). Results are promising, but confidence intervals are broad and additional, prospective research is warranted to validate findings.

Biomechanical Assessment of the NIOSH Lifting Equation in Asymmetric Load-Handling Activities Using a Detailed Musculoskeletal Model.

OBJECTIVE: To assess adequacy of the National Institute for Occupational Safety and Health (NIOSH) Lifting Equation (NLE) in controlling lumbar spine loads below their recommended action limits during asymmetric load-handling activities using a detailed musculoskeletal model, that is, the AnyBody Modeling System. BACKGROUND: The NIOSH committee employed simplistic biomechanical models for the calculation of the spine compressive loads with no estimates of the shear loads. It is therefore unknown whether the NLE would adequately control lumbar compression and shear loads below their recommended action limits during asymmetric load-handling activities. METHOD: Twenty-four static stoop lifting tasks at different load asymmetry angles, heights, and horizontal distances were performed by one normal-weight (70 kg) and one obese (93 kg) individual. For each task, the recommended weight limit computed by the NLE and body segment angles measured by a video-camera system (VICON) were prescribed in the participant-specific models developed in the AnyBody Modeling System that estimated spinal loads. RESULTS: For both individuals, the NLE adequately controlled L5-S1 loads below their recommended action limits for all activities performed in upright postures. Both individuals, however, experienced compressive and/or shear L5-S1 loads beyond the recommended action limits when lifting was performed near the floor with large load asymmetry. CONCLUSION: The NLE failed to control spinal loads below the recommended limits during asymmetric lifting tasks performed near the floor. APPLICATION: The NLE should be used with caution for extreme tasks involving load handling near the floor with large load asymmetry.

Assessment of noise in the airplane cabin environment.

OBJECTIVE: To measure sound levels in the aircraft cabin during different phases of flight. METHODS: Sound level was measured on 200 flights, representing six aircraft groups using continuous monitors. A linear mixed-effects model with random intercept was used to test for significant differences in mean sound level by aircraft model and across each flight phase as well as by flight phase, airplane type, measurement location and proximity to engine noise. RESULTS: Mean sound levels across all flight phases and aircraft groups ranged from 37.6 to >110 dB(A) with a median of 83.5 dB(A). Significant differences in noise levels were also observed based on proximity to the engines and between aircraft with fuselage- and wing mounted engines. Nine flights (4.5%) exceeded the recommended 8-h TWA exposure limit of 85 dB(A) by the NIOSH and ACGIH approach, three flights (1.5%) exceeded the 8-h TWA action level of 85 dB(A) by the OSHA approach, and none of the flights exceeded the 8-h TWA action level of 90 dB(A) by the OSHA PEL approach. CONCLUSIONS: Additional characterization studies, including personal noise dosimetry, are necessary to document accurate occupational exposures in the aircraft cabin environment and identify appropriate response actions. FAA should consider applying the more health-protective NIOSH/ACGIH occupational noise recommendations to the aircraft cabin environment.