Biomechanical Assessment of Three Rebar Tying Techniques

The National Institute for Occupational Safety and Health (NIOSH) conducted a study of ironworkers to evaluate their risk for developing back and hand injuries from hand-tying reinforcing steel bar and to investigate whether power tying tools can be an effective intervention for the prevention of work-related musculoskeletal disorders. A field investigation of biomechanical loading when using 3 techniques to tie together rebar was conducted. Researchers measured employees ‘ wrist and forearm movement with goniometers and videotaped and analyzed trunk postures. Manually tying rebar at ground level involved sustained deep trunk bending and rapid, repetitive, and forceful hand-wrist and forearm movements. Using a power tier significantly reduced the hand-wrist and forearm movements and allowed the ironworkers to use one free hand to support their trunk posture while tying. Adding an extension handle to the power tier allowed the ironworkers to tie rebar while standing erect, minimizing sustained trunk flexion.     

Developing an external domino accident prevention framework: Hazwim

Empirical research on major accident safety in the second largest chemical cluster worldwide, the Antwerp port area, supports the design of a meta-technical framework for optimizing external domino prevention. First, the majority of Seveso top tier companies have expressed a willingness to cooperate more intensively to protect themselves against potential off-site major accidents. Second, Hazop, What–If analysis and the Risk Matrix, interesting building blocks for such a framework, are frequently used risk analysis techniques at Seveso lower tier and Seveso top tier companies. The developed framework, called Hazwim, integrates these three complementary techniques into an effective standardized risk analysis framework for the prevention of external xdomino accidents in an industrial area. The main strengths of Hazwim are its completeness and its cost-effectiveness. The combination of techniques on the one hand and qualitative and quantitative data on the other, offers a comprehensive up-to-date list of cross-company domino hazards and recommended actions in the area under consideration. The Hazwim framework offers support to prevention managers and safety policy makers concerning external domino prevention.     

Prediction of Musculoskeletal Discomfort in a Pick and Place Task (A pilot study)

A pilot study was conducted regarding the effects of working posture, handling frequency, and task duration on musculoskeletal discomfort. Participants rated their discomfort perceived while performing a repetitive task at 8 different combinations of manipulations. Pauses between the work periods lasted 15 min. Discomfort was rated according to Borg’s category-ratio scale CR-10 and postures were recorded by an optoelectronic movement registration system. From linear multiple regression analysis equations for predicting discomfort at various body regions were obtained. Coefficients of determination especially point to trunk inclination and handling frequency as major determinants of musculoskeletal discomfort.     

Teams as boundaries: How intra‐team and inter‐team brokerage influence network changes in knowledge‐seeking networks

What role does an ego's brokerage location—within a team (intra‐team) or outside the team (inter‐team)—play in the evolution of an instrumental knowledge‐seeking network in terms of both proximal (i.e., within the team) and distal (i.e., outside the team) tie formation and tie decay? We address this question by drawing on literature about social networks, brokerage, and teams. We use temporally separated data from 302 students embedded in 97 teams to test our hypotheses about the impacts of intra‐team and inter‐team brokerage on proximal and distal network evolution, specifically on four network changes in knowledge‐seeking networks: proximal tie formation, proximal tie decay, distal tie formation, and distal tie decay. We find that these four changes depend on individual network brokerage location even after controlling for personality and task characteristics. Specifically, inter‐team brokers change their networks both within and outside their teams, whereas intra‐team brokers curtail their network changes. We argue that these opposite effects occur because inter‐team brokers have greater autonomy than intra‐team brokers. This study adds to the ongoing dialog about network evolution in social network literature and to the conversations about brokerage and its location in the context of team‐based work.     

驾驶工效综合评定座舱实验台的研制

为了在实验室内 ,能定性 /定量的研究飞机驾驶员工作时的复杂、实时操作感觉 ,开发了一台驾驶工效综合评定座舱实验台。该实验台主要由硬件 (包括座舱外壳、驾驶杆、座椅以及两台液晶显示器 )、软件两部分 (座舱视景系统、座舱仪表显示系统、飞机动力学系统、飞机控制系统、座舱网络通讯系统 )组成 ,通过使用眼动仪、触摸屏等设备来记录驾驶员的眼动及手动数据。该实验台可通过数据处理计算机实现人机界面的作业运动和进行工效综合评定。工效评定实验台的研制 ,可以提高座舱人机交互工效设计的可信度 ,是飞机驾驶舱面板优化设计的基础和依据 ,是研究保障安全飞行和提高作战能力以及效率等重大技术性能的重要手段。     

A Bayesian approach to construct bow tie diagrams for risk evaluation

Bow tie diagrams have become a popular method for risk analysis and safety management. This tool describes the whole scenario of a given risk graphically, and proposes preventive and protective barriers to reduce, respectively, its occurrence and its severity. The weakness of bow tie diagrams is that they are restricted to a graphical representation of different scenarios exclusively designed by experts that ignore the dynamic aspect of real systems. Thus, constructing bow tie diagrams in an automatic and dynamic way remains a real challenge. This paper proposes a new Bayesian approach to construct bow tie diagrams from real data and improve them by adding a new numerical that enables us to implement the appropriate preventive and protective barriers in a dynamic manner.     

Evaluation of design alternatives for sewing scissors with respect to hand performance,discomfort and usability

The effects of three re-designed models of sewing scissors on hand performance measures, discomfort and usability were investigated, and the results were compared with those of conventional scissors. Adjustments were made to the scissors handle with emphasis on more neutral wrist postures (bent handle - model A), correction of the thumb's position and movements (model B) and reducing hand/finger discomfort (model C) while working with the tool. The results showed some improvements in hand performance, muscular effort, usability and discomfort with model B compared to the conventional model. Better hand performance and usability and lower discomfort were recorded with model C compared to the conventional model. The results suggest that the correction of the thumb's position and movement (model B) or even reduced hand/finger discomfort (model C) are perhaps more important considerations in scissors design than improved wrist posture (model A) for improving users' performance and usability of the tool.     

Comparison of Two Methods for Judging Distances Near Overhead Power Lines

Sixteen certified crane operators performed several series of boom movements toward a segment of a typical power line using a 100-ton lifting capacity crane equipped with an 18-m boom, a single lifting cable, and a hard ball hook. The operators were instructed to stop the crane movement when the lifting cable reached the edge of the danger zone located 3 m from the power line. To achieve each maneuver, they evaluated the distance between the nearest wire and their crane using two methods: free sighting and the use of highly visible markers delineating the edge of the danger zone. The dependent measure was the distance between the lifting cable and the edge of the danger zone. Results showed that operators were generally unreliable when judging the distance between their crane and the power line when sighting the power line directly, but the use of markers proved to be much more precise and reliable in targeting the edge of the danger zone.     

Customer perceptions of justice in service transactions: the effects of strong and weak ties

This research used a justice perspective to investigate the effects of outcome favorability, opportunity for voice, and interpersonal treatment in a service context. Results suggest that all three variables influenced customer reactions to bank loan decisions. Weak‐tie customers were more sensitive to outcome favorability than strong‐tie customers. Strong‐tie customers were more sensitive to opportunity for voice than weak‐tie customers. Implications for improving customer reactions to service transactions are discussed. Copyright © 2001 John Wiley & Sons, Ltd.     

Sharps injury prevention for hospital workers

Objectives. The purpose of this study was to collect data on self-reported sharps injuries to develop best practices to reduce them. Methods. Data on sharps injuries were collected for the period of January-October 2008 using Adverse Event Notification Forms already in use at Sema Hospital. Results. On average, 0.2% of all self-reported injuries were sharps injuries averaging one injury per month. Housekeeping staff sustained 64% of such injuries, nurses sustained 36% (5 incidents). Outpatient clinics experienced the most injuries at 28%, followed by the Internal Diseases Inpatient Unit with 21% and the Medical Waste Room with 14%. Injuries often occurred during contact with medical waste bags (28%) and while replacing full sharp-boxes (14%). Conclusion. In summary, reducing needle stick injuries is an important component of the occupational and patient safety program at Sema Hospital. The research described in this study allowed the hospital to provide targeted interventions to increase awareness of the risks of needle stick injuries and reduce such injuries. The steps used in the study can be used in any health care organization in the world to design a customized improvement plan to reduce risk and injury.     

海河干流流域暴雨径流非点源污染负荷解析与控制策略

随着点源污染逐渐得到有效控制,非点源污染对海河干流流域水环境污染的贡献日益增大,对其污染负荷进行科学测算成为海河干流水质达标方案制订的重要前提。基于GIS技术,通过土地利用类型划分,利用PLOAD模型对海河干流的暴雨径流非点源污染负荷进行了计算。结果表明,海河干流流域建设用地的比例依海河流向自上而下逐渐递减,而涉农用地逐渐增加,城区地表径流与农业面源污染分别是上、下游地区重要的非点源污染负荷来源。关于流域的暴雨径流非点源污染负荷,CODCr为15 619.29 t/a,NH3-N为369.16 t/a,TN为851.20 t/a,TP为250.29 t/a。为改善海河干流水质,非点源污染控制应纳入流域的污染物总量控制计划中,与点源污染一起参与环境容量的分配与控制。     

Influence of trunk muscle activity and stability in front and back holding

Purpose. A tandem carrying style is often used in the workplace, but carrying approaches are different for two people because of the holding load in the tandem posture. To understand these carrying styles, this study aimed to investigate the patterns of muscle activity and stability of the trunk influenced by front and back holding of a heavy load. Methods. Electromyography data of eight trunk and two hip muscles, as well as displacements of the trunk, were recorded for analysis while subjects stood statically holding a handle in the front and back of the body with and without load. Results. Without load, muscle activities during front holding mirrored those during back holding. With load, greater muscle activities were observed in the dorsal muscles of the trunk and lesser activities were noted in the ventral muscles in the two holding styles. More frequencies of trunk oscillations occurred in front holding with and without load. Conclusions. The results revealed that back holding of load created more stability of the upper body, whereas front holding resulted in more instability of the trunk.     

旋风分离器磨损与防磨措施的研究

旋风分离器作为一种重要的气固分离设备,在石油化工、高炉喷煤、燃煤发电和环境保护等许多行业得到了广泛的应用.当旋风分离器分离煤、砂、飞灰、焦粉和氧化铝基催化剂等腐蚀性颗粒时,磨损是造成非计划停机的主要原因之一.就旋风分离器的结构、工作原理、磨损产生的机理与防磨措施问题展开讨论.     

Associations Between Worker Characteristics,Workplace Factors,and Work-Related Musculoskeletal Disorders: A Cross-Sectional Study of Male Construction Workers in Nigeria

Objective. This study assessed the association between worker characteristics, workplace factors, and work-related musculoskeletal disorders (WMSDs) in Nigeria’s construction industry. Methods. A cross-sectional site-by-site survey was conducted in 5 existing construction companies in Uyo, Nigeria. The subjects (n = 1200 males), aged 18-55 years, filled in the semistructured Nordic musculoskeletal questionnaire and the job content questionnaire on demographics, work and lifestyle characteristics, and workplace risk factors for WMSDs. Results. The overall prevalence of WMSDs was 39.25%. Differences in age, race, weight, body mass index (BMI), education status, and employment status were significantly associated with the prevalence of WMSDs. Prevalence according to trade was as follows: ironworkers highest at 49% and administrative staff lowest at 31%. Ironworkers (55.7%), administrative staff (53.3%), and security staff (38.7%) scored higher on physical, psychosocial, and individual risk factors, respectively. Workplace factors with increased odds for WMSDs were psychological demands and mental workload, age, BMI, low work experience, low education status, awkward movement of head and arms, working against force or vibration, fast work pace, and race. Conclusion. The recorded high prevalence was multifactorial in etiology; hence, multi-intervention strategies are required.     

Concussion attitudes,behaviors, and education among youth ages 12–17: Results from the 2014 YouthStyles survey

IntroductionThis study assessed young athletes' (ages 12 to 17) concussion attitudes and behaviors, particularly their self-reported experience learning about concussion and intentions to report a concussion and disparities in these experiences.MethodsWe used data from Porter Novelli's 2014 YouthStyles survey that is conducted each year to gather insights about American consumers.ResultsOf the 1,005 respondents, 57% reported sports participation. Fourteen percent reported they may have had a previous concussion, and among them 41% reported having a concussion more than once while playing sports. Males (17.7%) were significantly more likely to report having a concussion than females (10.0%; χ² (1) = 7.01, p = 0.008). Fifty-five percent of respondents reported having learned about what to do if they think they may have a concussion, and 92% reported that they would tell their coach if they thought they sustained a concussion while playing youth or high school sports. Youth from higher income families ($75,000–$124,999) were significantly more likely than youth from lower income families (less than $35,000) to report that they learned about what do if they suspected that they had a concussion.ConclusionAge of athlete, parental income level, athlete's sex, and living in a metro versus non-metro area led to disparities in athletes' concussion education. There is a need for increased access to concussion education and an emphasis on customizing concussion education efforts to meet the needs of different groups.Practical applicationWe identified athletes' self-reported previously sustained concussions and predictors of education related to concussion. Further research is needed to explore the age, gender and income gaps in concussion education among athletes.     

Hand tool injuries at work: A surveillance perspective

This paper reports results of a surveillance study of work injuries caused by power and nonpower hand tools. Analyzing 129,399 case reports of hand tool injury compensation claims from the 1983 Supplementary Data System of the Bureau of Labor Statistics, the authors determined that nonpower hand tool injury rates were highest in agriculture, followed by construction, mining, and retail trades. For power hand tool injury rates, the order was: construction, agriculture, manufacturing, and mining. Among nonpower hand tools, hand knives were prominent, causing large proportions of injuries to workers in the food preparation occupations and farm laborers. Power hand tool injuries were most often associated with saws, which accounted for large proportions of injuries to lumbermen, carpenters, and miscellaneous laborers. Most injuries could be described as acute trauma involving upper extremities, but musculoskeletal injuries were also documented in substantial numbers. The authors provide suggestions for focused investigations to follow the surveillance effort reported here.     

Differences in Eye and Hand Movements of Novice and Experienced Press Operators

Presses are very widely used in industrial and commercial companies and are often the source of serious accidents occurring during operation. Most of the accidents are due to inadequate training of novice operators. Continuous recordings of eye and hand movements of five novice operators and five experienced operators in press operation were made. Significant difference between novice and experienced operators was observed in eye fixation time, eye movement patterns, hand dwell time, and eye-hand coordination. Also, differences were observed in spatial distribution of eye fixations during the die-closing portion of a stroke. There were no significant differences between novice and experienced operators in the eye and the hand movement time. The results could be used as basic data to establish a guide determining the method and training period to train novice operators.     

Social movements,the occupational arena and changes in career consciousness: The case of women flight attendants

The impact of social movements as a major environmental influence in the evolution of career consciousness was analysed based on extensive interviews of women flight attendants. The aim was to elicit the women's view of their work lives over the past two decades. Flight attendants working in the 1960s entered with the expectation of a short-term job. From their accounts of personal development and from reviews of newspaper accounts, court cases and union documents, the influence of three major social movements became apparent. The Civil Rights Movement prompted flight attendants to challenge the legality of airline rules that prevented them from working past age 32. The Women's Movement reinforced the value and seriousness of women's commitment to a career and enabled flight attendants to challenge traditional notions of the incompatibility of occupation and family. The Occupational Health Movement, by addressing the collective problems of creating a healthy work environment, mobilized women flight attendants to recognize their long-term career investment. The findings suggest that social movements provide an additional dimension that is relevant for the future study of career development and continuing occupational socialization.     

大空间建筑火灾中烟气层界面的一种判定

采用摄像机拍摄大空间建筑内烟气运动的整个过程,从录像中获取烟气前沿和主体下降到各指示灯的时间,经时间截取法处理后得到烟气层界面形成及运动的实际时间,求烟气层高度x对该时间t的关系可得烟气运动曲线。把该曲线与采用热电偶测温法及目测法的结果进行对比可知,三者趋势较为吻合,表明摄像这种测量手段能较好地反映大空间建筑火灾中烟气流动的状况及部分运动规律。     

供电企业操作岗位员工安全胜任力模型的构建

为给供电企业的安全管理工作提供胜任力方面的理论依据和实践指导,通过采用系统编制的供电企业操作岗位员工安全胜任力调查问卷,对供电企业操作岗位员工进行整群随机抽样的问卷调查。对346份有效数据进行探索性因素分析,初步构建供电企业操作岗位员工安全胜任力的5因素模型;重新发放问卷,对141份有效数据进行的验证性因素分析支持了该模型因素结构的合理性;再次重新取样,对120份有效数据进行独立样本t检验和多层回归分析,检验5个安全胜任力因素对违章行为的影响。供电企业操作岗位员工安全胜任力模型以职业素养、安全意识、职业技能、身心健康和情绪稳定性5个因素为基本结构,其中,职业素养、安全意识、身心健康和情绪稳定性4个安全胜任力因素对违章行为具有显著负向影响。