Exposure to Methyl Methacrylate and Its Subjective Symptoms Among Dental Technicians,Tehran, Iran

Exposure to methyl methacrylate (MMA), total dust and health symptoms were investigated in 20 dental laboratories located in Tehran, Iran. Time-weighted average (TWA) of MMA and peak concentrations were determined, using XAD-2 tubes followed by GC-ID analysis. Total dusts were evaluated gravimetrically. Health symptoms were asked using a questionnaire. TWA for technicians with direct and indirect exposure to MMA were 327.28 ± 79.42 and 282.9 ± 41.84 mg/m³ , respectively. Peak concentration of MMA for those technicians were 337.0 ± 36.81 and 328.88 ± 45.40 mg/m³, respectively.

There were no significant differences between TWA of MMA and peak concentration in different weekly workdays; however, within-day variations were observed (P < .05).

TWA of MMA and peak concentration correlation with the laboratory volume were 0.61-0.65. Dust exposure of technicians was 2.35 ± 2.70 mg/m³. Cough and skin dryness were the common health symptoms. Smoking and asbestos exposure history were factors influencing cough prevalence (p < .05).

It is concluded that the current Short-Term Exposure Limit (STEL) is not low enough to protect technicians against the adverse effects caused by MMA.     

Assessment of the living and workplace health and safety conditions of site-resident construction workers in Tehran,Iran

Objectives. The purpose of this study was to assess living and workplace safety conditions of construction workers in Tehran, Iran. Methods. This cross-sectional study was conducted among 410 construction sites in a municipal area of Tehran whose municipal building permits were issued in 2011. Data on ventilation, workplace safety and hygiene were collected by direct observation and interviews with site foremen. Noise levels were estimated from 10 sound-level-meter stations in the municipality area. Results. Lack of ventilation in the workers’ rooms was abundant. Bathrooms were unhygienic and minimum requirements such as lighting and ventilation did not exist in 80% of the cases. In nearly 50% of large construction sites, sewage and garbage disposal were inappropriate. Elevator safety was poor at all sites and no measures for fall prevention were present in over 88% of active construction sites. This study showed that the mean 24-h equivalent continuous sound level L_eq was over 70?dB in 80% of the sites during weekdays. Conclusions. The results of this study revealed poor health and safety living and working conditions of construction workers in Tehran.     

Multiple dimensions of work-related risk factors and their relationship to work ability among industrial workers in Iran

Objectives. The present study was designed to investigate the simultaneous effects of physical, psychosocial and other work-related risk factors on the work ability index (WAI) score among industrial workers. Methods. This study used a cross-sectional design with a questionnaire survey. A total of 280 workers were included in the study. Data were collected using three questionnaires including the Persian version of the WAI, the Persian version of the job content questionnaire and an author-developed measure (to assess work-related factors, health-related factors and socio-demographic characteristics). Results. The majority of the participants were young, but they had poor WAI scores (mean 37.3?±?6.4) and 44.3% of them had poor or moderate work ability. Occupational accidents and injuries were found to be the strongest predictors of WAI scores. Additionally, there was a strong association between WAI scores and supervisor support, skill discretion, occupational training, sleep quality, work nature and educational level. Conclusions. Intervention programs should focus on improving supervisor support, sleep quality, job skills and knowledge and on decreasing physical and mental work demands. Additionally, implementing a comprehensive occupational health and ergonomics program for controlling and reducing hazardous working environments and occupational injury rates should be considered.     

Behavioural reactivation and subjective assessment of the state of vigilance--application to simulated car driving.

The frequency of some behaviour (such as self-centred gestures) increases during a task that leads to the occurrence of low-vigilance episodes. These gestures can be useful in stimulating oneself. A study carried out in 20 adults has enabled us to state that motor activity (recorded with an actimeter) increases with the duration of a monotonous driving task and sleep deprivation. The analysis of the scores recorded using the Karolinska Sleepiness Scale has shown that drivers can assess the deterioration of their state of vigilance according to the actual sleep preceding the driving test. Finally, the joint analysis of the subjective and objective data revealed a co-variation of these two types of indices. We discuss the stimulatory function of the motor activity in a task leading to the occurrence of low-vigilance episodes by investigating, among other things, the use, conscious or not, of this type of activity.     

Evaluation of workers' exposure to methylene diphenyl diisocyanate (MDI) in an automobile manufacturing company, Iran.

Evaluation of personal inhalation exposure to methylene diphenyl diisocyanate (MDI) among 39 employees, working in the window fixation and window glue processes in an automobile manufacturing company was performed. This study was conducted for both case and control groups. After sampling and sample preparation processes, MDI was determined with a UV-VIS spectrophotometer at 590 nm; the lung function was assessed with a digital spirometer, too. The average concentration of MDI in the window fixation, and window glue workplaces were 34.53 and 27.37 micro g/m3, respectively, which was lower than the threshold limit value (TLV) recommended by the American Conference of Governmental Industrial Hygienists (ACGIH) (51 micro g/m3). Respiratory symptoms in the exposed group were significantly different compared to the unexposed group (p < .05). Lung capacities in the case group were lower than in the control group (p < .05). Therefore, MDI can be easily measured making it possible to evaluate the adverse effects caused by occupational exposure.     

Harmful postures and musculoskeletal symptoms among sanitation workers of a fish processing factory in ghana: a preliminary investigation.

This study investigated musculoskeletal symptoms among sanitation workers of a fish-processing factory. The methods used included administration of a questionnaire, walk through observation, interview, task analysis and future workshop. All 27 male participants answered and submitted their questionnaires. Of the 11 operations identified, all except one was considered safe. Bent back, bent legs, and heavy manual handling were observed to impose intolerable health risk on participants. This corresponds with questionnaire results in which musculoskeletal symptoms were mostly prevalent in the neck, the shoulder, the low back, the wrists/hands and the upper back regions. Poor psychosocial complaints were also made on the job. There was no significant correlation (p < .05) between musculoskeletal symptoms and age, working hours and length of service. Neither was any significant correlation observed (p < .05) between psychosocial work factors and musculoskeletal symptoms. Recommendations such as task redesign to eliminate high-risk elements in operations, workplace changes and worker training were suggested.     

Harmful postures and musculoskeletal symptoms among fish trimmers of a fish processing factory in ghana: a preliminary investigation.

This study investigated musculoskeletal symptoms among fish trimmers (skinners and polishers) in a fish processing factory in Ghana. The methods used included administration of questionnaire, walk through observation, interview, task analysis and future workshop. All 50 female participants answered and submitted their questionnaires. Of the 11 operations performed by skinners only 1 was rated as low risk. Also of the 12 operations performed by polishers only 2 were rated as low risk. Neck side bending, neck flexion, prolonged standing, shoulder elevation, abducted arms, repetitious reaching forward and wrist deviation were observed in most operations. This corresponds with questionnaire results in which musculoskeletal symptoms were mostly prevalent in the neck, the shoulder, the low back, the wrist/hand and the knee regions. There was no significant correlation (p < .05) between musculoskeletal symptoms and age, working hours and length of service. Task redesign, workplace changes and worker training were suggested to improve the work.     

Working conditions,psychological/physical symptoms and occupational accidents. Bayesian network models

Each day thousands of workers suffer occupational accidents of varying degrees of severity. Accidents at work render workers incapable of carrying out their day to day activities, either temporarily or permanently, and they also have detrimental effects on family life, the company, and the general public. In order to reduce the occupational accident rate, it is necessary to determine the causes of those accidents. Although there are many different types of accidents, they generally stem from poor working conditions. The purpose of this study was to analyze the influence of working conditions on occupational accidents from data gathered in the VI National Survey of Working Conditions (VI NSWCs) in 2007. This survey utilized a random sample of the active population of Spain. The sample comprised 11,054 people (5917 males and 5137 females). In order to carry out the study, a probabilistic model was built using Bayesian networks. The model included the following variables: hygiene conditions, ergonomic conditions, job demands, physical symptoms, psychological symptoms, and occupational accidents. The study demonstrated that there were strong relationships between hygiene conditions and occupational accidents; it has been shown that poor hygienic conditions duplicate the probability of accident. Physical symptoms increased almost 50% due to poor ergonomic conditions. And finally, high job demands almost duplicated the psychological symptoms. The investigation also showed a high degree of interdependence between physical and psychological symptomatologies and the relationship between these and occupational accidents.     

Cardiovascular stress, energy expenditure and subjective perceived ratings of fire fighters during typical fire suppression and rescue tasks.

The study determined physiological and psychophysical responses to fire fighters' typical activities. Self-reported assessment of the most demanding fire fighting/rescue tasks were collected with a questionnaire. Then 19 voluntary fire fighters performed 3 simulated fire fighting/rescue tasks in protective clothing. Heart rate (HR), blood pressure and energy expenditure were measured; the rating of perceived exertion (RPE) was assessed with the Borg scale. The questionnaires showed that carrying out victims, fire suppression and resuscitation were classified as heavy load; climbing stairs with a hose as moderate load. According to RPE the subjects considered their effort during ladder climbing fairly light and only somewhat harder during stair climbing and carrying out injured people. The study demonstrated that typical fire fighting/rescue tasks were associated with high energy expenditure and imposed considerable cardiovascular stress. The Borg scale appeared not suitable for assessing perceived exertion in fire fighters during simulated tasks.     

利益冲突群体的安全人性及其弱点

根据安全人性需求理论对利益冲突群体形成的原因进行了分析,在安全人性理论的基础上揭示了利益冲突群体安全人性的本质。通过统计分析我国近14年发生的群体性事件,得出了我国群体性事件的特点、矛盾主体、原因。运用蝴蝶突变理论对群体性事件发生的原因进行分析,构建了群体性事件发生的过程机理模型,提出了应对群体性事件发生的思路,总结出利益冲突群体安全人性的应用领域。     

Noise exposure as related to productivity, disciplinary actions, absenteeism, and accidents among textile workers

A sample of 2458 workers exposed to average noise levels ranging from 80 to 99 dBA in different operations of three textile mills was studied with respect to their productivity, work rule violations, absenteeism, and accidents. The three mills were in rural, suburban, and urban locations. Noise exposure levels were measured in individual departments of the mills, and workers were interviewed to ascertain socioeconomic background, work history data, and health status. Workers' job attitude was rated by their supervisors, and data about their productivity, disciplinary reports, absenteeism, and accidents were collected from plant records. Results of the study suggested that workers in departments with high noise levels (above 90 dBA) had more disciplinary actions and absenteeism and lesser productivity than those in departments with low noise exposure (below 90 dBA). Disciplinary actions showed the greatest difference between the high-noise and low-noise departments followed by production incentives, production efficiency, and absenteeism. Noise appeared to affect the quality of work as reflected by disciplinary actions for material damage, and this effect was higher in weaving and spinning operations which involved vigilance tasks. The frequency and severity rates of accidents in highnoise departments were greater than in low-noise departments. Certain personal and socioeconomic factors affected high vs. low noise exposure differences found among workers for the investigated variables. These effects were most apparent for absenteeism and, to a lesser extent, productivity. Disciplinary actions did not appear to be influenced by any such individual factors. It was concluded that noise abatement in the textile industry could be beneficial to worker productivity and well being and contribute to more economically effective operation.     

Multiple interactions of hazard exposures, role stressors and situational factors, and burnout among nurses.

This was a cross-sectional study which looked into the interaction between situational factors, role stressors, hazard exposure and personal factors among 135 nurses in the Philippine General Hospital. More than half (58.5%) of the respondents reported being ill due to work in the past year, and 59.3% missed work because of an illness. Regression showed factors associated with burnout were organizational role stress, hazard exposure, self-efficacy, age, number of working years, illness in the past 12 months, migraine, dizziness, sleep disorder, cough and colds, and diarrhea. After multiple regression analysis, organizational role stress (p = .000), migraine (p = .001), age (p = .018) and illness in the past 12 months (p = .000) were found to be significant predictors of burnout. The contribution of the study is in advancing new concepts in the already existing framework of burnout, and thus, assisting nurses and hospital administration in on controlling this problem.     

日本、韩国、东盟与我国石棉危害预防控制现状

简要介绍了日本、韩国、东盟各国以及我国石棉危害预防控制工作的现状,提出我国当前形势下应开展石棉危害现状的调研,研究建立石棉使用的许可管理制度,加强温石棉及其替代品危害性研究,并加强有关领域石棉危害预防控制法规政策的制定。     

Musculoskeletal symptoms as related to ergonomic factors in Iranian hand-woven carpet industry and general guidelines for workstation design.

Carpet weaving is a high risk occupation for developing musculoskeletal disorders (MSDs). The objectives of the present study, which was carried out in the Iranian hand-woven carpet industry, were determination of the prevalence of MSD symptoms, identification of major factors associated with MSD symptoms and development of guidelines for workstation design. 1,439 randomly selected weavers participated in this study. A questionnaire was used to collect data on MSD symptoms. The results revealed that the prevalence rates for symptoms in different body regions were high as compared to the general Iranian population (for neck, back and large joints, p <.0001). The results of multivariate analyses showed that major ergonomic factors associated with musculoskeletal symptoms were loom type, working posture, daily working time and seat type. Based on the results, some general guidelines for designing weaving workstations were developed. A prototype test showed that the new workstation was acceptable for subject tests and that it improved working posture.     

The effects of attitude,subjective norm and self-efficacy on intention to benchmark: a comparison between managers with experience and no experience in benchmarking

Competitive benchmarking is a management technique used to compare company performance. The practices and processes of one's own organization are compared with the best performance of other organizations to set targets and learn ways to make improvements. Drawing on Ajzen's (1985) theory of planned behaviour, we examined the effects of attitude, subjective norm and self-efficacy on managers' intentions to undertake benchmarking in their organization. A sample of 49 managers with benchmarking experience was compared with 46 managers with no experience of the practice. Consistent with the theory of planned behaviour, attitude and subjective norm were significant predictors of intention to benchmark. However, contrary to the theory, self-efficacy was not a significant predictor. For managers with benchmarking experience, attitudinal beliefs toward the technique was the strongest predictor of benchmarking intention. For managers with no benchmarking experience, normative beliefs about the views of key groups such as senior management and employees, was the strongest predictor of intention to benchmark. These findings support the possibilities of refinement of the theory of planned behaviour to postulate the primacy of subjective norms in introduction of group behaviour and attitude primacy in continuation of group behaviour. The findings are also discussed in relation to beliefs about benchmarking and for preparing managers who are about to introduce or continue a benchmarking programme.     

中美日突发公共事件应急管理机制的比较研究

针对中国、美国和日本的应急管理机制,分析比较了其基本构成和运行机制,总结了各自的优缺点及可借鉴的先进经验,指出为了构建科学有效的突发公共事件应急管理机制必须:①进一步完善应急联动机制及应急指挥系统,实行统筹规划;②增加应急财政投入,完善公共财政应急反应机制;③加强应急法制建设,明确政府、企业和公民等的职责;④整合应急资源,加强应急管理机制与国防动员机制的结合;⑤着眼于基层综合灾害风险管理,实现应急工作的全民参与。