International Journal of Occupational Safety and Ergonomics最新文献

With software developments and advances in display technologies substantially improved, augmented reality (AR) application has gained popularity. In this study, we discuss using classic PowerPoint and AR for two kinds of scaffolding tasks (task-lifeline assembly and hedge assembly) for users with different spatial ability. We considered both objective and subjective measures of performance, i.e., correct rate and system usability and the ITC-sense of presence inventory (ITC-SOPI) scale. The results of the study show that participants using AR achieved higher operating performance than those using PowerPoint. Furthermore, the users' learning effect was influenced by spatial ability when using PowerPoint. Participants with high spatial ability achieved higher performance than participants with low spatial ability in PowerPoint. However, participants who used AR as a training method did not show significantly different operating performance at different levels of spatial ability. Consequently, AR was believed to be a potential method for enhancing training performance.

A questionnaire survey and an event-related potential (ERP) experiment were used to reveal the impact of safety attitudes on risk perception. The results revealed that during hazard identification, the N130 amplitude of subjects with negative safety attitude was significantly higher, which implied that subjects with negative safety attitude were more likely to feel confused. During risk analysis, subjects with positive safety attitude were more inclined to overestimate the probability and damage degree of risks; subjects with positive safety attitudes displayed higher P150 and late positive potential amplitudes, which indicated that subjects with positive safety attitudes devoted more attention to risks in the early stage of risk analysis and had a more intense affective response in the later period. The risk judgment ability of subjects with positive safety attitude was affected by time pressure, and they exhibited higher risk judgment accuracy only under no time pressure.

Objectives. Associations between shift-work, musculoskeletal symptoms and absenteeism are poorly investigated in the manufacturing industry. This study aimed to investigate associations between working schedule, musculoskeletal symptoms and days of absenteeism among pulp and paper industry workers. Methods. Musculoskeletal symptoms of 904 workers were assessed through the Nordic Musculoskeletal Questionnaire. χ² tests assessed associations between being a day-worker or shift-worker, the prevalence of musculoskeletal symptoms and days of absenteeism. Results. A significant association was found between working schedule and symptoms in the lower back in the last 12 months, with shift-workers presenting higher prevalence than day-workers (p = 0.022). Significant associations were also found between days of absenteeism and symptoms in the shoulders (p = 0.002), which mostly led to absenteeism of 100-365 days; elbows (p < 0.001), wrists/hands (p = 0.045) and ankles/feet (p = 0.042), which produced absenteeism mostly of 25-99 days; and dorsal region (p = 0.001), which mainly led to absenteeism of 10-24 days. No associations were found between working schedule and days of absenteeism (p = 0.265). Conclusion. Shift-work is associated with increased prevalence of lower back symptoms, but seems not to influence days of absenteeism. Shoulders seem to be the region leading to higher days of absenteeism, followed by elbows, wrists/hands, ankles/feet and the dorsal region.

Objectives. This study aimed to investigate the consistency between results of the American Conference for Governmental Occupational Hygienists (ACGIH) threshold limit value (TLV) for hand activity and proposed action levels of objective measurements in risk assessments of work-related musculoskeletal disorders. Methods. Wrist velocities and forearm muscular load were measured for 11 assemblers during one working day. Simultaneously, each assembler's hand activity level (HAL) during three sub-cycles was rated twice on two separate occasions by two experts, using a HAL scale. Arm/hand exertion was also rated by the assemblers themselves using a Borg scale. In total, 66 sub-cycles were assessed and assigned to three exposure categories: A) below ACGIH action limit (AL) (green); B) between AL and TLV (yellow); and C) above TLV (red). The median wrist velocity and the 90^th percentile of forearm muscular load obtained from the objective measurements corresponding to the sub-cycles were calculated and assigned to two exposure categories: A) below or C) above the proposed action level. Results. The agreement between ACGIH TLV for hand activity and the proposed action level for wrist velocity was 87%. Conclusions. The proposed action level for wrist velocity is highly consistent with the TLV. Additional studies are needed to confirm the results.

Firefighters in such serious environments (i.e., hazardous flames and radiant heat, high air temperatures, hot chemicals and liquids) must wear fire protective clothing during fire extinguishing and rescue operations. Many studies in the field of fire protective clothing have been conducted to evaluate the protective, mechanical and comfort performance of fire protective clothing. A comprehensive review of the literature has been undertaken to provide a better understanding of single-layer and multilayer fire protective clothing with protective, mechanical and comfort performance. Factors affecting the durability of protective clothing in the light of their expected retirement age and a number of significant standards for laboratory and manikin testing are discussed. The comfort of wearing clothing is another aspect that needs special consideration when designing a multilayered fire protective suit. A number of emerging technologies have been outlined to address the various challenges of the present day.

Objectives. This study aimed to develop a predictive model for work-related musculoskeletal disorders (WRMSDs) among radiographers. Methods. A survey was conducted in seven hospitals in two cities with radiographers using the ergonomic assessment for radiographers questionnaire. Logistic regression, confirmatory factor analysis and structural equation modelling (SEM) were utilized to establish statistical relationships between independent factors and musculoskeletal complaints. Results. Of 165 respondents, 75.2% reported musculoskeletal pain in the past 12 months, with lower back pain the most prevalent (58.8%). Adjusting for covariates, musculoskeletal pain significantly correlated with body mass index < 23 (odds ratio [OR] 0.06, 95% confidence interval [CI] [0.005, 0.914]), smoking status (OR 0.274, 95% CI [0.751, 6.195]), fixed work break schedule (OR 2.839, 95% CI [1.123, 7.176]), sustained posture (OR 4.854, 95% CI [1.203,19.594]) and prolonged standing or walking (OR 7.499, 95% CI [1.086, 51.753]). The fit measures indicate a moderately good fit of the proposed model to the observed data. However, latent variables did not exhibit significant associations with WRMSD in SEM. Conclusions. The model suggests that WRMSDs among radiographers moderately correlate with underweight, smoking status, fixed work breaks, sustained posture and extended periods of standing or walking. The absence of significant associations between latent variables and WRMSDs suggests the presence of unexplored factors influencing the outcome.Trial registration: Clinical Trials Registry India identifier: CTRI/2021/09/036992.

Objectives. This study aimed to evaluate the influence of individual characteristics (sex, age, body mass index [BMI] and smoking habits) on the tolerance time, pain ratings and rewarming time of hand cold stress testing (CST). Methods. We included 153 subjects (63% men) working in a Swedish open-pit mine (participation rate 41%). The right hand was immersed in 3 °C circulating water for up to 45 s. Pain ratings were registered every fifth second using a visual analog scale. Results. The tolerance time (mean ± standard deviation) was 35 ± 12 s for men and 29 ± 14 s for women (p = 0.007). The youngest age group (18-29 years) had the longest tolerance time, while the oldest group (54-65 years) had the shortest (p = 0.005). Women had significantly higher pain ratings than men after 5, 10 and 25 s. The group with the highest BMI had the shortest rewarming time (p < 0.001). Conclusions. Age and sex influenced the tolerance time of hand CST, while only sex affected the pain ratings and BMI the rewarming time. When performing CST in future studies, these parameters should be considered.

Prolonged sitting with awkward posture during sewing results in musculoskeletal disorders among sewing operators. This study aimed to identify the compatibility of the sewing furniture with operators' anthropometry. Therefore, 13 anthropometric measurements of 368 sewing operators were collected and compared with sewing furniture dimensions. The results showed that all anthropometric measurements other than hip breadth were larger for male participants. In addition, statistical analysis performed on the collected data showed significant variation compared to the existing dimensions of sewing machines. Results also indicated a high mismatch for different dimensions of the sewing table and chair, such as seat height, seat width, seat depth, table depth, etc. For this reason, sewing operators often experience musculoskeletal disorders. Finally, this study recommends some guidelines for designing the sewing workstation, which might act as a basis for manufacturers or importers to set provisions for sewing machines.

Objectives. The aim of this study was to evaluate the relationship between core endurance tests and physical activity level, balance, ergonomics and pain in office workers. Methods. The study included 57 office workers who had been employed for at least 1 year. Core endurance was assessed using McGill core endurance tests. Physical activity, balance, pain and ergonomic risks were evaluated with the international physical activity questionnaire (IPAQ), timed up and go (TUG), visual analog scale (VAS) and rapid office strain assessment (ROSA), respectively. Results. A significant correlation was found between balance and static core endurance tests. However, no significant correlation was found between ergonomics and physical activity level and core endurance tests except for trunk extension and prone bridge tests. In addition, there was a significant difference in core endurance tests for patients with and without regular exercise habits. Waist circumference and hip circumference measurements were found to be significantly negatively associated with static core tests. Conclusion. Core endurance was found to be associated with exercise habits, balance, hip and waist circumference and ergonomics in office workers. Improving core endurance may be beneficial for preventing musculoskeletal risks in office workers.

Bus driver anger due to passenger misbehavior may lead to serious bus accidents, yet there are no mature tools available to capture bus driver reactions during driver-passenger conflicts. The bus driver anger scale (BDAS) and the bus driver anger expression inventory (BDAX) were developed to measure the anger levels and expressions of drivers in such conflicts. A bus driver anger model was developed based on 400 questionnaires in Changsha, China. The findings indicate that drivers are most likely to be angered by passenger violations and quarrels among passengers. Drivers irritated by passenger irregularities tend to employ personal aggressive expression or adaptive/constructive expression. Disputes among passengers may lead drivers to resort to unreasonable methods of venting their emotions. Moreover, passengers' rude behaviors can trigger bus drivers' aggressive personal expressions. Therefore, it is necessary to establish passenger regulations and encourage drivers to express their anger reasonably in driver-passenger conflicts.