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Slips, trips, and falls (STFs) are the second leading cause of non-fatal injuries and can lead to fatal incidents in the mining industry. Hazard identification is an essential first step in remediating STF hazards and creating a safer work environment. Previous research has identified industry-specific risk factors for STFs, evaluated exposures to those risk factors, and developed taxonomies of the hazards for the construction and farming sectors. In comparison, ErgoMine-a mobile device application-based ergonomics audit tool-is the only systematic evaluation tool that covers STF hazards in the mining industry. However, ErgoMine was not specifically developed to address STF hazards. This paper describes the development of a taxonomy that helps identify STF hazards at surface mining sites and provides recommendations to address these hazards to inform future evaluation tools. The objective was to develop a taxonomy that was self-explanatory, observable, repeatable, and solution oriented. In addition to current regulations, standards and guidelines were used to develop the taxonomy to ensure the focus was beyond basic compliance. A detailed description of how the STF hazard taxonomy was created for walkways, stairways, and fixed ladders is provided, along with two specific applications of its use. The STF hazard taxonomy can be used to develop tools like checklists and ergonomics audits to identify and remediate slip, trip, and fall hazards at surface mining facilities, thereby improving worker safety., (Published by Elsevier Ltd.)

A web-based survey was conducted of ergonomics practitioners holding certifications in the U.S., Canada, Great Britain, Australia, and New Zealand. The survey follows 12 years after an earlier initial survey reported by Dempsey et al. (2005). Approximately 1221 eligible participants were invited by e-mail to participate, and 405 surveys were included in the final analysis. The survey queried use of basic instruments relevant to ergonomic practice as well as more specific analytical tools such as observational techniques for assessing postural demands of work and instrumentation for direct measurement of such demands. Some ergonomic assessment methods appear to have increased in their overall use by U.S. ergonomists compared to 2005 data. This was observed for: RULA, REBA, Psychophysical Upper Extremity Data, Strain Index, and ACGIH TLV for Hand Activity Level. There is minimal evidence of increased overall use of direct measurement approaches in the U.S. There appear to be geographic differences between countries/continents in terms of use of various methods. The use of mobile device/smart phone "apps" by ergonomists was queried and these technologies presently appear to be in early adoption phase with 24-28% of practitioners reporting use of an app in their ergonomics practice., (Published by Elsevier Ltd.)

Using psychophysics, the maximum acceptable forces for pushing have been previously developed using a magnetic particle brake (MPB) treadmill at the Liberty Mutual Research Institute for Safety. The objective of this study was to investigate the reproducibility of maximum acceptable initial and sustained forces while performing a pushing task at a frequency of 1min(-1) both on a MPB treadmill and on a high-inertia pushcart. This is important because our pushing guidelines are used extensively as a ergonomic redesign strategy and we would like the information to be as applicable as possible to cart pushing. On two separate days, nineteen female industrial workers performed a 40-min MPB treadmill pushing task and a 2-hr pushcart task, in the context of a larger experiment. During pushing, the subjects were asked to select a workload they could sustain for 8h without "straining themselves or without becoming unusually tired, weakened, overheated or out of breath." The results demonstrated that maximum acceptable initial and sustained forces of pushing determined on the high inertia pushcart were 0.8% and 2.5% lower than the MPB treadmill. The results also show that the maximum acceptable sustained force of the MPB treadmill task was 0.5% higher than the maximum acceptable sustained force of Snook and Ciriello (1991). Overall, the findings confirm that the existing pushing data developed by the Liberty Mutual Research Institute for Safety still provides an accurate estimate of maximal acceptable forces for the selected combination of distance and frequency of push for female industrial workers.

The objective of this study is to investigate the workstation and tool effects on the responses of the powered hand tool operator reacting against the impulsive reaction forces that may be associated with upper extremity musculoskeletal disorders. The study demonstrated a means of direct measurement of force at the interface between the tool and the operator. Fifteen experienced male operators performed three independent work configurations: pistol grip and right angle tools used on the horizontal surface and pistol grip tools used on the vertical surface, in the laboratory. A full factorial experiment consisting of 36 conditions was designed to examine the effects of working height, distance, tool, and fastener joint hardness on handle displacement and grip forces. The results indicate that operator responses were affected by different factors depending on the work configuration. When pistol grip tools were used on the vertical surface, the mean handle displacement decreased from 9.9 degrees to 7.3 degrees as the working height increased from 30 cm below shoulder to 30 cm above shoulder. When right angle tools were used, the greatest handle displacement (51.1mm) and grip force (84.7% MVC) during torque reactions were measured at 30 cm below elbow and 40% forward reach away from the operator. This study provides quantitative information that can be used for workstation design and tool selection to reduce the torque reaction experienced by powered nutrunner operators.

The industrial revolution significantly changed the way work was organized and analyzed by the introduction and widespread implementation of the division of labor philosophy. This philosophy has continued to dominate work design, and has evolved beyond the factory to include many facets of service industries, and even professional occupations. The analysis of manual work, particularly materials handling tasks, remains an active domain of ergonomics research and practice. Many of the task-analytic tools used for workplace analysis are rooted in the philosophy of dividing work into elements, analyzing the individual elements, and synthesizing the results into conclusions about the entire job, including the risk of contracting musculoskeletal disorders (MSDs). The authors discuss the notion that the nature of modern work, which is characterized by multiple tasks in a complex time pattern, and the complex nature of MSDs, which are influenced by biomechanical as well as psychological, political, and economic factors, may limit the effectiveness of classical task analytic techniques in preventing MSDs.

Knife sharpness can affect the productivity of meatpacking operations as well as the forces to which meat cutters are exposed. This report describes the development and evaluation of a "sharpness tester" designed to meet the criteria that the system be portable for field use at meatpacking plants, requires no special skills to operate, provides a non-destructive test of the entire blade edge, and incorporates a test motion that is representative of meat cutting. The system was bench tested for sensitivity to incremental changes in blade sharpness; suitability of the test material as a surrogate for red meat; and ability to detect variations in sharpness along the length of the blade. A graphical presentation showed that changes in cutting forces measured with the system correspond to changes in blade sharpness. Measurements made with both the test material and with red meat showed good correlation (r = 0.89). The system demonstrated the capacity to detect differences in sharpness in regions of a knife edge as well as providing visual evidence of defects along the edge of a knife blade.

A survey of Certified Professional Ergonomists (CPEs) was conducted to gather information on the types of basic tools, direct and observational measurement techniques, and software used by practitioners. The motivation for the survey was to better understand what types of tools and methods practitioners use, their opinions of these tools, and to potentially gain an understanding of the constraints or preferences that influence this selection. Reasons for using or not using a selection of tools were also surveyed. Of 578 surveys that were delivered to CPEs and Associate Ergonomics Professionals, 308 were returned for a response rate of 53%. The respondents tended to be biased towards physical ergonomics, as the survey primarily focused on this area of ergonomics. A high percentage of respondents reported using tape measures, video cameras, stopwatches and digital cameras. The most commonly used observational methods were those involving manual materials handling, whereas the most commonly used direct measurement tools were pinch and grip dynamometers and push/pull gauges. The frequency and type of checklists, software, and anthropometric data used are summarized.

Meat cutting causes a much greater incidence of upper extremity disorders than industry averages. Grip forces and cutting moments in meat cutting operations can be very high. Recently published studies indicate that the blade sharpness can significantly affect force exposure during meat cutting. Two attributes that have not been investigated with respect to force exposure during meat cutting are the effect of blade edge angle and blade finishing after sharpening (honing and polishing). This study investigated the effect of three blade edge angles and three post-sharpening finishing protocols on the grip forces and cutting moments exerted by professionals during two different meatpacking operations. A fine polish finishing protocol significantly reduced cutting time by 25.3%, mean grip force by 21.2%, and mean cutting moment by 28.4% over a coarser finishing protocol during one of the operations. No significant differences in the exposure variables were found between the blade edge angle conditions.

The force exposure associated with meat cutting operations and the effect of knife sharpness on performance and productivity have not been well documented. Specialized hardware was used to measure grip force and reactive moments with 15 professional meat cutters performing lamb shoulder boning, beef rib trimming and beef loin trim operations in a field study conducted in two meat packing plants. A system for measuring relative blade sharpness was developed for this study. Mean and peak cutting moments observed for the meat cutting operations, averaged across subjects were 4.7 and 17.2 Nm for the shoulder boning, 3.5 and 12.9 Nm for the rib trim, and 2.3 and 10.6 Nm for the loin trim, respectively. Expressed as percent of MVC, mean grip forces of 28.3% and peak grip forces of 72.6% were observed overall. Blade sharpness was found to effect grip forces, cutting moments and cutting time, with sharper blades requiring statistically significantly lower peak and mean cutting moments, and grip forces than dull knives. Efforts aimed at providing and maintaining sharp blades could have a significant impact on force exposure.

A repeated measures 2 x 2 factorial design using a psychophysical experimental methodology was performed to quantify the effect of shaft design (straight and bent shaft) and shoveling technique (forward and backward progression) on heart rate, perceived exertion, productivity, trunk kinematics and load kinetics. Ten male subjects performed four 8-min trials of snow shoveling on a paved asphalt surface. The most notable finding was significantly less trunk flexion with the bent shaft (41.4 degrees ) than with the straight shaft design (49.2 degrees ). The study results led to a recommendation of a bent-shaft shovel for the purpose of reducing trunk flexion. In the absence of any strong positive evidence and due to poor subjective response to backward progression while shoveling, this technique was not recommended.

A relatively neglected topic in manual materials handling (MMH) research is the impact of the accuracy of task parameter measurements on the application of various assessment methods. A laboratory experiment was conducted to investigate the accuracy of NIOSH equation parameter measurements made by eight subjects following a 4-h training session. Five individual tasks were measured; two were single tasks and three were part of a multiple-component simulated palletizing operation. Significant differences between reference parameter measurements and average measurements made by subjects were found. The sensitivity analysis showed that frequency and horizontal location are the most important parameters. These parameters also tended to have the highest measurement errors. Recommendations for increasing the effectiveness of training programs for NIOSH equation users based on the results of the study are presented.

A new and improved method to feedforward neural network (FNN) development for application to data classification problems, such as the prediction of levels of low-back disorder (LBD) risk associated with industrial jobs, is presented. Background on FNN development for data classification is provided along with discussions of previous research and neighborhood (local) solution search methods for hard combinatorial problems. An analytical study is presented which compared prediction accuracy of a FNN based on an error-back propagation (EBP) algorithm with the accuracy of a FNN developed by considering results of local solution search (simulated annealing) for classifying industrial jobs as posing low or high risk for LBDs. The comparison demonstrated superior performance of the FNN generated using the new method. The architecture of this FNN included fewer input (predictor) variables and hidden neurons than the FNN developed based on the EBP algorithm. Independent variable selection methods and the phenomenon of 'overfitting' in FNN (and statistical model) generation for data classification are discussed. The results are supportive of the use of the new approach to FNN development for applications to musculoskeletal disorders and risk forecasting in other domains.

A comprehensive ergonomics evaluation of retail ice cream shops, including field and laboratory data collection, was conducted using a human:workplace model approach to ergonomics practice. The goal of the evaluation was to provide recommendations to enhance the health, safety, and productivity of shop employees. Active and passive surveillance and facility walk-throughs were used to guide the selection of analyses. A primary focus of the investigation was quantifying the task demands of scooping ice cream, which have not been documented in the literature. This goal was accomplished through the use of a custom-designed instrumented ice cream scoop. Data were collected at an ice cream shop under typical conditions, while the laboratory experiment investigated task demands of ice cream scooping over a range of realistic temperatures. Manual materials handling task analyses and anthropometric evaluations comprised the majority of other analyses performed. Recommendations are presented that are applicable to the operation of retail ice cream shops that serve hard (i.e., scooped) ice cream.

A biomechanical investigation of four satchels designed for the purposes of manually carrying and delivering mail was conducted. Twenty United States Postal Service carriers participated in the study. The satchels differed primarily in the presence/absence of a waist belt, the number and design of the shoulder straps, and the number of pouches. The biomechanical analyses were comprised of postural (shoulder and hip) deviation measurements, estimated compressive forces at the L5/S1 joint, soft tissue pressure on the shoulder, spinal torsion during mail retrieval, force distribution between the feet, and an anthropometric evaluation. The results indicated that a satchel with two shoulder straps and two pouches was more desirable than the single-pouch satchels from a biomechanics standpoint.

A field study was conducted to compare four satchels designed for the purposes of manually carrying and delivering mail. The satchels differed primarily in the presence/absence of a waist belt, the number and design of the shoulder strap(s) and the number of pouches. The evaluation consisted of questionnaires and interviews of slightly more than 300 letter carriers employed by the United States Postal Service. The questionnaires focused on 10 main areas of interest; ease of adjustability and handling, comfort, suitability and durability of materials, anthropometric applications, impact on other activities, ease of motion in retrieving mail, ease of motion in carrying the satchel, versatility of use in diverse climates, protection of mail from damage due to rain and snow, and defense against dog attacks. The primary conclusion was that the satchel with two shoulder straps and two pouches, which results in more symmetric loading than the other satchels, is the most desirable of the satchels tested. However, there are problems with the satchel that need to be addressed, such as concerns about the use of the satchel for defense from dog attacks.