National Institute For Occupational Safety And Health Research Research Articles

Measuring the benefits of occupational safety and health research with economic metrics: Insights from the National Institute forOccupational 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.

Competencies for the Competent Person: Defining Workplace Examiner Competencies from the Health and Safety Leader’s Perspective

The ability to identify hazards during a workplace examination is a critical skill for mineworkers to have in order to maintain a safe workplace. While research suggests that being able to successfully recognize hazards requires a complex set of competencies, it is unclear which competencies are most critical to adequately perform a workplace examination. This paper presents a hazard recognition competencies framework as an explanation of the competencies that affect mineworker hazard recognition. To better understand how the industry is selecting and preparing workplace examiners, researchers from the National Institute for Occupational Safety and Health (NIOSH) interviewed nine health and safety (H&S) professionals at surface stone, sand, and gravel mine sites throughout the USA. A primary purpose of these interviews was to verify the competencies included in the hazard recognition competencies framework and to understand why these competencies are critical. Finally, the results of this study are presented within the context of current NIOSH research findings related to hazard recognition.

Cryogenic Air Supply for Cooling Built-in-Place Refuge Alternatives in Hot Mine

Built-in-place (BIP) refuge alternatives (RAs) are designed to provide a secure space for miners who cannot escape during a mine emergency. Heat and humidity buildup within RAs may expose miners to physiological hazards such as heat stress. To minimize the risk of heat stress, Title 30 Code of Federal Regulations (CFR), or 30 CFR, mandates a maximum allowable apparent temperature (AT) for an occupied RA of 35 °C (95 °F) (MSHA 2008 [1]). The National Institute for Occupational Safety and Health (NIOSH) has conducted extensive research on the thermal environment of occupied RAs intended for use in underground coal mines. NIOSH research has demonstrated that a fully occupied BIP RA can exceed the AT limit by > 5.6 °C (10 °F) in mines with elevated mine strata and air temperatures (Bissert et al. 2017 [2]). In this circumstance, an RA cooling system could provide a solution. This paper provides an overview of test methodology and findings as well as guidance on improving the performance of a cryogenic air system prototype by optimizing the flow rate, increasing the tank storage capacity, and improving the efficiency of the heat exchanger of the cryogenic system. This may enable BIP RAs to meet the 35 °C (95 °F) AT limit in mines with elevated temperatures. The information in this paper is useful for RA manufacturers and mines that may choose to implement a cryogenic air system as a heat mitigation strategy.

Review of NIOSH Cannabis-Related Health Hazard Evaluations and Research.

Since 2004, the National Institute for Occupational Safety and Health (NIOSH) has received 10 cannabis-related health hazard evaluation (HHE) investigation requests from law enforcement agencies (n = 5), state-approved cannabis grow operations (n = 4), and a coroner's office (n = 1). Earlier requests concerned potential illicit drug exposures (including cannabis) during law enforcement activities and criminal investigations. Most recently HHE requests have involved state-approved grow operations with potential occupational exposures during commercial cannabis production for medicinal and non-medical (recreational) use. As of 2019, the United States Drug Enforcement Administration has banned cannabis as a Schedule I substance on the federal level. However, cannabis legalization at the state level has become more common in the USA. In two completed cannabis grow operation HHE investigations (two investigations are still ongoing as of 2019), potential dermal exposures were evaluated using two distinct surface wipe sample analytical methods. The first analyzed for delta-9-tetrahydrocannabinol (Δ9-THC) using a liquid chromatography and tandem mass spectrometry (LC-MS-MS) method with a limit of detection (LOD) of 4 nanograms (ng) per sample. A second method utilized high performance liquid chromatography with diode-array detection to analyze for four phytocannabinoids (Δ9-THC, Δ9-THC acid, cannabidiol, and cannabinol) with a LOD (2000 ng per sample) which, when comparing Δ9-THC limits, was orders of magnitude higher than the LC-MS-MS method. Surface wipe sampling results for both methods illustrated widespread contamination of all phytocannabinoids throughout the tested occupational environments, highlighting the need to consider THC form (Δ9-THC or Δ9-THC acid) as well as other biologically active phytocannabinoids in exposure assessments. In addition to potential cannabis-related dermal exposures, ergonomic stressors, and psychosocial issues, the studies found employees in cultivation, harvesting, and processing facilities could potentially be exposed to allergens and respiratory hazards through inhalation of organic dusts (including fungus, bacteria, and endotoxin) and volatile organic compounds (VOCs) such as diacetyl and 2,3-pentanedione. These hazards were most evident during the decarboxylation and grinding of dried cannabis material, where elevated job-specific concentrations of VOCs and endotoxin were generated. Additionally, utilization of contemporary gene sequencing methods in NIOSH HHEs provided a more comprehensive characterization of microbial communities sourced during cannabis cultivation and processing. Internal Transcribed Spacer region sequencing revealed over 200 fungal operational taxonomic units and breathing zone air samples were predominantly composed of Botrytis cinerea, a cannabis plant pathogen. B. cinerea, commonly known as gray mold within the industry, has been previously associated with hypersensitivity pneumonitis. This work elucidates new occupational hazards related to cannabis production and the evolving occupational safety and health landscape of an emerging industry, provides a summary of cannabis-related HHEs, and discusses critical lessons learned from these previous HHEs.

The development and testing of a prototype mini-baghouse to control the release of respirable crystalline silica from sand movers

ABSTRACTInhalation of respirable crystalline silica (RCS) is a significant risk to worker health during well completions operations (which include hydraulic fracturing) at conventional and unconventional oil and gas extraction sites. RCS is generated by pneumatic transfer of quartz-containing sand during hydraulic fracturing operations. National Institute for Occupational Safety and Health (NIOSH) researchers identified concentrations of RCS at hydraulic fracturing sites that exceed 10 times the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) and up to 50 times the NIOSH Recommended Exposure Limit (REL). NIOSH research identified at least seven point sources of dust release at contemporary oil and gas extraction sites where RCS aerosols were generated. NIOSH researchers recommend the use of engineering controls wherever they can be implemented to limit the RCS released. A control developed to address one of the largest sources of RCS aerosol generation is the NIOSH mini-baghouse assembly, mounted on the thief hatches on top of the sand mover. This article details the results of a trial of the NIOSH mini-baghouse at a sand mine in Arkansas from November 18–21, 2013. During the trial, area air samples were collected at 12 locations on and around a sand mover with and without the mini-baghouse control installed. Analytical results for respirable dust and RCS indicate the use of the mini-baghouse effectively reduced both respirable dust and RCS downwind of the thief hatches. Reduction of airborne respirable dust ranged from 85–98%; reductions in airborne RCS ranged from 79–99%. A bulk sample of dust collected by the baghouse assembly showed the likely presence of freshly fractured quartz, a particularly hazardous form of RCS. Planned future design enhancements will increase the performance and durability of the mini-baghouse, including an improved bag clamp mechanism and upgraded filter fabric with a modified air-to-cloth ratio. Future trials are planned to determine additional respirable dust and RCS concentration reductions achieved through these design changes.

Air cleaning performance of a new environmentally controlled primary crusher operator booth.

The National Institute for Occupational Safety and Health (NIOSH) cooperated with 3M Company in the design and testing of a new environmentally controlled primary crusher operator booth at the company's Wausau granite quarry near Wausau, WI. This quarry had an older crusher booth without a central heating, ventilation and air conditioning (HVAC) system, and without an air filtration and pressurization system. A new replacement operator booth was designed and installed by 3M based on design considerations from past NIOSH research on enclosed cab filtration systems. NIOSH conducted pre-testing of the old booth and post-testing of the new booth to assess the new filtration and pressurization system's effectiveness in controlling airborne dusts and particulates. The booth's dust and particulate control effectiveness is described by its protection factor, expressed as a ratio of the outside to inside concentrations measured during testing. Results indicate that the old booth provided negligible airborne respirable dust protection and low particulate protection from the outside environment. The newly installed booth provided average respirable dust protection factors from 2 to 25 over five shifts of dust sampling with occasional worker ingress and egress from the booth, allowing some unfiltered contaminants to enter the enclosure. Shorter-term particle count testing outside and inside the booth under near-steady-state conditions, with no workers entering or exiting the booth, resulted in protection factors from 35 to 127 on 0.3- to 1.0-μm respirable size particulates under various HVAC airflow operating conditions.

Fall prevention research and practice: a total worker safety approach.

Slips, trips, and falls (STF) represent a serious hazard to workers and occupants in many industries, homes, and communities. Often, the cause of a STF incident is multifactorial, encompassing human, environmental, and task risk factors. A STF-related disability can greatly diminish the occupational capability and quality of life of individuals in both the workplace and the home. Countering STF hazards and risks both on and off the job and on all aspects of control measures is a “total worker safety” matter, a challenging yet tangible undertaking. As the federal organization responsible for conducting research for the prevention of work-related injuries in the United States, the National Institute for Occupational Safety and Health (NIOSH) has been conducting research on STF controls for some decades. Many NIOSH research outcomes have been utilized for STF prevention in workplaces, with potential for prevention in homes as well. This paper summarizes the concept of total worker safety for STF control, NIOSH priority research goals, major activities, and accomplishments, and some emerging issues on STF. The strategic planning process for the NIOSH research goals and some identified research focuses are applicable to the development and implementation of global STF research goals.

Laboratory Faceseal Leakage Evaluation of N95 Filtering Facepiece Respirators Against Nanoparticles and “All Size” Particles

National Institute for Occupational Safety and Health (NIOSH)-certified N95 filtering facepiece respirators (FFRs) are used for respiratory protection in some workplaces handling engineered nanomaterials. Previous NIOSH research has focused on filtration performance against nanoparticles. This article is the first NIOSH study using human test subjects to compare N95 FFR faceseal leakage (FSL) performance against nanoparticles and “all size” particles. In this study, estimates of FSL were obtained from fit factor (FF) measurements from nine test subjects who participated in previous fit-test studies. These data were analyzed to compare values obtained by: 1) using the PortaCount Plus (8020A, TSI, Inc., MN, USA) alone (measureable particle size range 20 nm to > 1,000 nm, hereby referred to as the “all size particles test”), and 2) using the PortaCount Plus with N95-CompanionTM accessory (8095, TSI, Inc., Minn.) accessory (negatively charged particles, size range ∼40 to 60 nm, hereby referred to as the “nanoparticles test”). Log-transformed FF values were compared for the “all size particles test” and “nanoparticles test” using one-way analysis of variance tests (significant at P < 0.05). For individual FFR models, geometric mean (GM) FF using the “nanoparticles test” was the same or higher than the GM FFs using “all size particles test.” For all three FFR models combined, GM FF using the “nanoparticles test” was significantly higher than the GM FF using “all size particles test” (P < 0.05). These data suggest that FSL for negatively charged ∼40–60 nm nanoparticles is not greater than the FSL for the larger distribution of charged and uncharged 20 to > 1,000 nm particles.

Occupational Injury Prevention Research in NIOSH

This paper provided a brief summary of the current strategic goals, activities, and impacts of the NIOSH (National Institute for Occupational Safety and Health) occupational injury research program. Three primary drivers (injury database, stakeholder input, and staff capacity) were used to define NIOSH research focuses to maximize relevance and impact of the NIOSH injury-prevention-research program. Injury data, strategic goals, program activities, and research impacts were presented with a focus on prevention of four leading causes of workplace injury and death in the US: motor vehicle incidents, falls, workplace violence, and machine and industrial vehicle incidents. This paper showcased selected priority goals, activities, and impacts of the NIOSH injury prevention program. The NIOSH contribution to the overall decrease in fatalities and injuries is reinforced by decreases in specific goal areas. There were also many intermediate outcomes that are on a direct path to preventing injuries, such as new safety regulations and standards, safer technology and products, and improved worker safety training. The outcomes serve as an excellent foundation to stimulate further research and worldwide partnership to address global workplace injury problems.

Field-portable methods for monitoring occupational exposures to metals

Millions of workers are employed in manufacturing, mining, construction, and other industries where significant amounts of airborne metals and metal compounds are generated. Depending on the work practices, processes, techniques, and locations, exposures to airborne and surface sources of a variety of metals can cause occupational illness. These exposures can lead to a plethora of adverse health effects such as lung disease, anemia, cancer, asthma, dermal sensitization, dermatitis and neurological damage. The ability to monitor worker exposures to metals on-site in the field has been a goal of the National Institute for Occupational Safety and Health (NIOSH) since the early 1990s. In the last 15 years or so, several field-portable procedures for metals have been developed, evaluated and published as NIOSH methods. These methods, published in the NIOSH Manual of Analytical Methods, describe field screening tests and on-site analysis for lead, hexavalent chromium and beryllium. Some of these methods have also been published in the form of ASTM International voluntary consensus standards. This paper gives an overview of NIOSH research and development efforts on field screening and portable analytical methods for metals in the workplace. The goal of such efforts has been to provide screening and analytical tools that can be used on-site in the field to aid in the prevention of excessive exposures to toxic metals in the workplace.

Thermally induced filter bias in TEOM mass measurement

Researchers at the National Institute for Occupational Safety and Health (NIOSH) have long used stationary tapered element oscillating microbalances (TEOMs) in laboratory settings. They have served to assess the mass concentration of laboratory-generated particulates in experimental dust chambers and they provide a reference method for comparison with other particulate-measuring instruments. Current NIOSH research is focused on further adapting TEOM technology as a wearable personal dust monitor (PDM) for coal mining occupations. This investigation's goal is to help identify, quantify, and provide means for resolving certain TEOM-related error. The present research investigated bias caused by thermal effects on filter assemblies. New filters used in the PDM for 8 h tests show an average positive bias of 25.5 microg, while similar tests of equivalent filters used in two 1400A model TEOMs show an average positive bias of 34.3 microg. The derived bias values allow correction of previously collected biased data. Also, pre-heating the filters for 24 h at 46 degrees C shows significant bias reduction, with PDM pre-heated filters subsequently averaging -3.3 microg and 1400A TEOM filters averaging 5.9 microg. On a single-point comparison to gravimetric sampling, a 25.5 microg bias is only significant at low mass loadings. At 2.5 mg, this bias represents a negligible 1% of the mass measurement. If ordinary linear regression is used, the bias is still insignificant. However, if the more valid weighted linear regression is used, it gives more weight to the smaller dependent variable values, which are more impacted by the bias. Consequently, what is 1% bias on a single high-mass value can translate into a larger bias percentage at high-mass values when performing a weighted regression on data that include a large number of low-mass values.

NIOSH Research Efforts to Prevent Musculoskeletal Disorders in the Healthcare Industry

Healthcare workers, including orthopaedic nurses, face a number of risk factors in the workplace for musculoskeletal disorders such as back and shoulder injuries. These disorders are associated with excessive back and shoulder loading due to manual patient handling, applying excessive forces during pushing and/or pulling of objects, required use of awkward postures during patient care, and working long hours and shiftwork. No healthcare workers are immune from injury because workers in all clinical areas are exposed to occupational risk factors, including hospitals, nursing homes, emergency services, critical care, operating rooms, orthopaedic units, and home healthcare environments. This article includes a summary of the scientific efforts of the researchers and their partners at the National Institute for Occupational Safety and Health (NIOSH) in evaluating and developing the best practice recommendations for reducing risk of these disorders for exposed workers. The studies conducted by NIOSH researchers and their partners approach the problem from a variety of perspectives, ranging from comprehensive epidemiological studies examining the effectiveness of implementation of a safe patient handling and movement program to laboratory studies evaluating the biomechanical stress associated with using patient handling equipment, and education training programs for use in schools of nursing to educate new workers about safe work practices. Results of these studies have provided scientific evidence that significant occupational risks for musculoskeletal disorders exist and that effective interventions are available to reduce the risk for these workers.

Determining particle size distributions in the inhalable size range for wood dust collected by air samplers.

In the absence of methods for determining particle size distributions in the inhalable size range with good discrimination, the samples collected by personal air sampling devices can only be characterized by their total mass. This parameter gives no information regarding the size distribution of the aerosol or the size-selection characteristics of different samplers in field use conditions. A method is described where the particles collected by a sampler are removed, suspended, and re-deposited on a mixed cellulose-ester filter, and examined by optical microscopy to determine particle aerodynamic diameters. This method is particularly appropriate to wood dust particles which are generally large and close to rectangular prisms in shape. Over 200 wood dust samples have been collected in three different wood-products industries, using the traditional closed-face polystyrene/acrylonitrile cassette, the Institute of Occupational Medicine inhalable sampler, and the Button sampler developed by the University of Cincinnati. A portion of these samples has been analyzed to determine the limitations of this method. Extensive quality control measures are being developed to improve the robustness of the procedure, and preliminary results suggest the method has an accuracy similar to that required of National Institute for Occupational Safety and Health (NIOSH) methods. The results should provide valuable insights into the collection characteristics of the samplers and the impact of these characteristics on comparison of sampler results to present and potential future limit values. The NIOSH Deep South Education and Research Center has a focus on research into hazards of the forestry and associated wood-products industry, and it is hoped to expand this activity in the future.

NIOSH research initiatives to prevent back injuries to nursing assistants, aides, and orderlies in nursing homes.

Over the past 100 years, advances in nutrition, modern medicine, public health, and a multitude of public health improvements have increased the life expectancy of U.S. residents. The fact that Americans are living longer has resulted in extensive growth in our elderly population and a rapid employment growth that delivered about 2 million new jobs between 1980 and 1989 in the health care workforce. The Bureau of Labor Statistics Injury and Illness Data for nursing homes rose from 10.7 to 18.6 injuries or illnesses per 100 full-time workers between 1980 and 1992. The injury and illness rates among nursing home workers are partly due to the physical stress of providing round-the-clock assistance with the basic activities of daily living, such as getting in and out of a bed or chair, as well as bathing and toileting. The National Institute for Occupational Safety and Health (NIOSH) is conducting a series of research studies to identify strategies to reduce the risk of musculoskeletal injuries to workers in nursing homes. NIOSH has funded two laboratory evaluations of resident transferring methods and one field study in an actual nursing home. The purpose of this paper is to describe the key findings from past NIOSH research initiatives and to present an overview of future research.

Occupational health priorities for health standards: the current NIOSH approach.

Government agencies responsible for protecting the public from the adverse effects of toxic chemicals must set priorities for research, regulatory action, protocol testing, and monitoring due to the vast number of toxic chemicals and the limited resources available to these agencies. The National Institute for Occupational Safety and Health (NIOSH) must set priorities for research on hazards encountered in the workplace. Priorities are also utilized by NIOSH in preparing criteria for recommended occupational standards which are forwarded to the Occupational Safety and Health Administration (OSHA), U.S. Department of Labor, for possible promulgation. For various reasons, including rapidly changing conditions in the American workplace, NIOSH has instituted a revised priorities program. In the future, NIOSH research and recommended standards activities will focus not only on individual chemicals, but also on industries, occupations, chemical classes, and general industrial processes. NIOSH has also implemented a new program which will allow recommended control procedures for certain chemicals to be forwarded to OSHA in a shorter time period than has been experienced previously.