International Journal of Occupational Safety and Ergonomics最新文献

This study attempted to optimize the adaptive neuro-fuzzy inference system (ANFIS) using particle swarm optimization (PSO) and a genetic algorithm (GA) for calculating occupational risk. Numerous studies have shown that the ANFIS is a good approach for predicting engineering problems. However, it is not well investigated in the area of risk assessment. The proposed techniques were evaluated using various statistical indices, i.e., mean absolute error (MAE) and root mean square error (rmse), to characterize their performance. To test the prediction performance of the proposed technique, a comparison with three well-known machine learning approaches, i.e., artificial neural network (ANN), logistic regression (LR) and support vector machine (SVM), was conducted. The obtained results indicate that ANFIS-PSO achieved better prediction performance for both the training and testing phases. Furthermore, the comparative analysis showed that the proposed model is competitive and suitable for occupational risk prediction.

Soldering is common in electrical product manufacturing, but the task load in small units is unquantified. Therefore, this study aimed to establish the occurrence of task load due to soldering work, analyzing the effects of age and sex among workers in small manufacturing units. The task load of 102 soldering workers from four small-scale manufacturing units was assessed using the National Aeronautics and Space Administration task load index (NASA-TLX) questionnaire, covering six dimensions: physical demand, mental demand, temporal demand, effort, performance and frustration. Statistical analyses were performed using the Mann-Whitney U test, the Kruskal-Wallis test and ordinal regression, considering age, sex and work characteristics as independent variables. Age and work characteristics significantly influenced task loading, with a high prevalence of physical, mental and temporal demands and effort among soldering workers. These findings could lead to interventions in terms of the workstation design.

A qualitative analysis of the communication process of subway teams was performed from the perspective of cognitive psychology in this study. The findings revealed that the communication process exhibited characteristics consistent with a Markov process, and then a model was approved to calculate the probability of miscommunication based on Markov processes. As communication within subway teams is a two-way process, a model for the dynamic probability of miscommunication based on the Markov two-way communication mode was derived. The model was subsequently validated through a case study involving a screen door fault event. The research results indicate that the actual cognitive communication process yields a significantly lower probability of miscommunication compared to the values obtained from the technique for human error rate prediction (THERP) manual. This demonstrates the effectiveness of dynamic two-way communication as a means of reducing miscommunication and confirms the feasibility and effectiveness of the proposed calculation model.

The objective of the study was to examine the mechanical and electrostatic properties of poly(vinyl chloride) intended for use in protective footwear. The poly(vinyl chloride) material was made with graphite (flake side dimensions 5 and 10 µm) additive in weight concentration variants from 0.5 to 10.0%. The influence of incorporating graphite in the polymer matrix was evaluated by testing mechanical parameters and electrostatic parameters (according to Standard No. EN ISO 20344:2021). In addition, the surface morphology, analysis of thermal properties and stability were evaluated. The results indicated the highest increase in tear resistance for the variant containing 1.5- 2.0% graphite. In terms of electrostatic parameters, the addition of graphite caused an increase in electrical resistance. Based on the obtained preliminary test results, it can be concluded that the use of graphite additive can increase the mechanical properties and find application in the production of protective footwear components.

Objectives. In parallel with the rising world population, consumption is increasing. Seafarers work intensively for the continuity of consumption. Vessel crew work under contract for specific periods. When the contract ends, new personnel join the ship while others leave. Personnel are transferred to the ship's location by plane for the change. During this flight, seafarers are exposed to rapid time zone changes that affect their circadian rhythms. This situation causes jet lag disorder, which is a sub-factor of fatigue. It is known that ship personnel sometimes board vessels without giving them a rest period when they arrive at the destination port by plane and quickly start operations under their duties and responsibilities. Seafarers can participate in risky operations without realizing that they are under the effect of jet lag. Methods. In this study, data were obtained by applying a survey to 114 seafarers. A jet lag disorder that may occur while the seafarers' join the ship was analyzed with an independent-sample t test using SPSS version 23. Results and Conclusion. There was a positive relationship between the seafarers' work performance at the time they joined the ship and the duration they stayed at the hotel.

In wildland firefighting, the air gap (AG) between clothing and the human body can effectively decrease heat transferred to skin but has a negative impact on thermal aging of clothing. Heat transfer to skin from a fire source can led to burn injuries and heat is transmitted between adjacent AGs parallel to the skin surface. An open AG simulator was developed to explore the dual effects of the AG on fabric thermal aging and skin thermal protection. Results indicated that thermal aging of fabrics was affected by the size and boundary form of the AG. Open and closed AGs increased second-degree burn times by 37.2-232.9 and 32.4-160.3%, respectively. The 12-mm and 18-mm open AGs decreased thermal aging of the fabric while maintaining good thermal protection compared to other AG conditions. The findings indicate that an appropriate AG design can balance thermal aging and thermal protection of firefighter suits.

Objectives. Musculoskeletal disorders (MSDs) represent a prevalent global occupational health concern, primarily associated with high biomechanical solicitations, mental workload and work pace. Although cobots have shown promise in reducing risks of MSDs, a question of interest still persists as to how the pace in hybrid human-machine collaboration will affect the operator, in terms of both physical and cognitive health and the production.Methods. This study aimed to analyse the impact of pace on productivity, operators' posture and mental workload in a human-cobot collaboration. The study, involving 20 participants engaged in a collaborative task with a cobot under three cobot-led paces, assessed productivity rapid upper limb assessment (RULA) scores (posture), dual task performance (cognitive resources) and NASA task load index (NASA-TLX) scores (workload).Results. The findings revealed that an excessively high pace had counterproductive effects, leading to reduced efficiency and increased susceptibility to MSDs, both in terms of physical and mental workloads.Conclusion. In the context of a human-cobot collaboration, it is imperative to adapt the pace to operators' abilities in order to ensure optimal productivity while preserving their health, emphasizing the need for a balanced approach to pace management in such collaborative work scenarios.

Objectives. This research aimed to describe the distribution and occurrence of work-related collisions involving paramedics across Quebec and compare these results with collisions of general vehicles. Methods. This retrospective study spanned 11 years of data (2010-2020) extracted from Société de l'assurance automobile du Québec (SAAQ) road safety statistics. Statistical tests including a paired t test and the Mann-Kendall test were used for temporal analysis of aggregated numbers of injury and non-injury collisions in 17 regions of Quebec. A descriptive analysis and logit regression were used to compare the various factors, e.g., crash and environmental characteristics associated with ambulance and general vehicle collisions. Results. A higher percentage of ambulance collisions occurred at intersections (43.32%), in 50 km/h speed limit zones (48.29%), in commercial areas (48.29%) and on all types of two-way roads (62.05%). Logit models indicate that there is a significant association (p < 0.05) between collision severity and a variety of factors, including asphalt conditions, collision types and locations. Conclusion. The study results are consistent with prior research showing that Quebec paramedics have comparable incidents and collision causes related to environmental, weather and road factors. Our findings suggest several specific areas for policymakers to focus on regarding ambulance collision reduction.

This literature review investigates the application of wide dynamic range compression (WDRC) to enhance hearing protection and communication among workers in a noisy environment. Given the prevalence of noise-induced hearing loss, there is a major need to provide workers, with or at risk of hearing loss, with a solution that not only protects their hearing but also facilitates effective communication. WDRC, which amplifies softer sounds while limiting louder sounds, appears a promising approach. This review explores 46 articles investigating WDRC performance on speech intelligibility and loudness perception in noise for individuals with normal hearing or mild to moderate hearing loss. The findings illustrate a complex interplay between several factors such as WDRC parameters, noise types and personal factors. Although WDRC holds promise for enhancing auditory protection and communication in noisy work settings, targeted research towards customizable and adaptive WDRC configurations is crucial for optimizing its application across industrial noise environments.

This article examines the dual effects of occupational health and safety cost (OHSC) fluctuations due to the occupational accident number (OAN), and the impact of the OAN on operating period costs (OPCs). Initially, OHSCs, OANS and other operational data from the company were compiled to build a foundational infrastructure. Subsequently, econometric analysis using regression techniques was conducted to identify relationships between OHSCs and OANs, and between OHSCs and OPCs. Findings suggest that a 1% increase in OAN correlates with a 0.18% rise in OPC, while a 1% increase in OHSC corresponds to a 0.26% increase in OAN. The study also indicates that effective OHSCs can lead to a reduction in OAN, and without the expenditure of OHSCs in the relevant period, the likelihood of OANs occurring increases by approximately 84 times. These insights underscore the critical role of OHSCs in managing operational risks and enhancing performance.