Determination of the injury probability among coal mine workers

Purpose. Establishing regularities of change in the injury probability and development of a methodology for determining the injury probability of coal mine workers to improve the occupational health and safety (OSH) management system efficiency. Methods. Methods of mathematical statistics and mathematical analysis were used in the data processing of coal mine workers’ injuries; probability theory and risk theory were applied for setting equations to determine the injury probability; correlation and regression analysis were used to determine the density and nature of the dependences reflecting changes in the injury probability. Findings. A calculator has been developed to compute the injury probability of an employee. This instrument distributes the probability into three “zones”: high probability – “red zone”, medium probability – “yellow zone”, and low probability – “green zone”. The injury probability for all employees of the mine administration was calculated. It was found that the clo-sest relationship between the number of injuries and the calculated probability is observed for mining sites (medium probability) and for tunneling sites (high probability). For employees with a calculated high injury probability, in most cases, the causes of injury were objective and less dependent on employees themselves. For employees with a medium probability, the causes independent of and dependent on employees were approximately equally correlated. In the case of employees with a low probability, the main reasons were subjective – dependent on the employees themselves. For employees in the main operational sites (mining and tunneling), the cause of injury is directly related to the specifics of the production operations performed: the presence of loose space. Originality. For the first time, relationships were determined between the injury probability and the profession. We also established relationships between experience at the enterprise, age, marital status of an employee and the injury causes, as well as between the actual number of injuries and the calculated injury probability. Practical implications. A method for determining the injury probability of coal mine workers has been developed and implemented. The ways of improving the methods for calculating the injury probability are determined.

The Assessment of Physical Risk Taking: Construct Validation of a New Behavioral Measure

Risk taking is a complex heterogeneous construct that has proven difficult to assess, especially when using behavioral tasks. We present a new measure – the Assessment of Physical Risk Taking (APRT) – as a comprehensive assessment of the probability of success and failure, and magnitude of reward and punishment of different types of physically risky behaviors with a variety of outcome scores. Participants (N = 224) completed APRT in a laboratory setting, half of whom had a 1.5 s delay interposed between button presses. Main effects, two-way interactions among five within-subject factors, and interactions between the within-subject factors and Delay were estimated for four APRT outcome scores using Generalized Estimating Equations. Results indicated that Injury Magnitude and Injury Probability exerted much stronger effects than the other factors. APRT scores correlated with self-reported risk taking in thrilling activities specifically, but only for those who did not have a delay between APRT responses.

Injury by Contarinia (Diptera: Cecidomyiidae) to early-seeded and late-seeded canola in northeastern Saskatchewan, Canada, and assessment of seed treatments for midge control

A three-year field study in northeastern Saskatchewan, Canada, determined the effects of seeding date and seed treatment on feeding injury by Contarinia Róndani (Diptera: Cecidomyiidae) midges to canola, Brassica napus Linnaeus (Brassicaceae), and subsequent seed yield. Emergence cage monitoring indicated the presence of two generations of midges at the four locations observed. Intensity of midge injury to canola was low, but damaged plants were common. Field location and seeding date influenced probability of midge injury and canola growth stage. The wettest of the four locations had the greatest number of midges but low levels of probability of damage in two of three years. Early-seeded plots had higher injury probability than late-seeded plots, with the highest probability of injury occurring one to two weeks after flowering commenced. Seed treatment marginally affected midge injury ratings, suggesting that insecticide efficacy dissipated before the midges attacked. Seed yield was higher in early-seeded than in late-seeded plots in two of three years, despite the greater level of damage seen in early-seeded plots. Overall, the research showed that the agronomic benefits of early seeding outweighed the effects of the midge damage observed; therefore, producers in the Canadian prairie provinces should seed canola when conditions are most agronomically suitable.

An Examination of Isolated and Interaction-Based Biomechanical Metrics for Potential Lower Neck Injury Criteria

Lower neck injuries inferior to C4 level, such as fractures and dislocations, occur in motor vehicle crashes, sports, and military events. The recently developed interaction criterion, termed Nij, has been used in automotive safety standards and is applicable to the upper neck. Such criterion does not exist for the lower neck. This study was designed to conduct an analysis of data of lower neck injury metrics toward the development of a mechanistically appropriate injury criterion. Axial loads were applied to the crown of the head of post mortem human subject (PMHS) head-neck complexes at different loading rates. The generalized force histories at the inferior end of the head-neck complex were recorded using a load cell and were transformed to the cervical-thoracic joint. Peak force and peak moment (flexion or extension) were quantified for each test from corresponding time histories. Initially, a survival analysis approach was used to derive injury probability curves based on peak force and peak moment alone. Both force and moment were considered as primary variables and age a covariate in the survival analysis. Age was found to be a significant (p<0.05) covariate for the compressive force and flexion moment but insignificant for extension moment (p>0.05). A lower neck Nij formulation was done to derive a combined interactive metric. To derive cadaver-based metrics, critical intercepts were obtained from the 90% injury probability point on peak force and peak moment curves. The PMHS-based critical intercepts derived from this study for compressive force, flexion, and extension moment were 4471 N, 218 Nm, and 120 Nm respectively. The lower cervical spine injury criterion, Lower Nij (LNij), was evaluated in two different formulations: peak LNij and mechanistic peak LNij. Peak LNij was obtained from the LNij time history regardless of when it occurred. Mechanistic peak LNij was obtained from the LNij time history only during the time when the resulting injury mechanism occurred. Injury mechanism categorization included compression-flexion, compression-extension, and those best represented by a more pure compression-related classification. Mechanistic peak LNij was identified based on the peak timing of the injury mechanism. Peak LNij and mechanistic peak LNij were found to be significant (p<0.05) predictors of injury with age as a covariate. The 50% injury probability was 1.38 and 1.13 for peak LNij and mechanistic peak LNij, respectively. These results provide preliminary data based on PMHS tests for establishing lower neck injury criteria that may be used in automotive applications, sports and military research to advance safety systems.