Development of an ergonomics risk assessment tool for repetitive task assessment (RTRA).

BACKGROUND: Most ergonomics assessment tools for repetitive task have been used in industries which are mainly focused on assessing the biomechanical risk factors that affect musculoskeletal disorders (MSDs) rather than the psychosocial and work environment risk factors. OBJECTIVE: To develop a tool for Repetitive Task Risk Assessment (RTRA) and Rapid Upper Limb Assessment (RULA) that can identify biomechanical, physical stress and psychosocial risk factors, prioritize risk reduction action and systematic record keeping. METHODS: The study consisted of 2 phases; tool development and evaluation of the contents of risk factors by 7 ergonomic experts and intra-rater and inter-rater reliability and validity tests of the tool by 1 researcher and 9 Thai practitioners to assess 30 repetitive tasks. RESULTS: RULA was modified by adding more biomechanical risk, combining psychosocial and work environment risk factors lead to MSD become the first prototype of RTRA. The Item-Objective Congruence Index (IOC) validated 20 items on usability of each step of the RTRA ranged between 0.64 and 0.93. The examination of the overall intra-rater reliability was 0.932 (95% CI: 0.862-0.967) and the overall inter-rater was 0.956 (95% CI: 0.909-0.978). CONCLUSION: The tool has high test-retest reliability. There is a suggestion for researchers to understand more on the identification of multiple risk factors in one assessment tool and consider a risk-level rating and scoring for prioritizing risk reduction.

Informal Workers in Thailand: Occupational Health and Social Security Disparities.

Informal workers in Thailand lack employee status as defined under the Labor Protection Act (LPA). Typically, they do not work at an employer's premise; they work at home and may be self-employed or temporary workers. They account for 62.6 percent of the Thai workforce and have a workplace accident rate ten times higher than formal workers. Most Thai Labor laws apply only to formal workers, but some protect informal workers in the domestic, home work, and agricultural sectors. Laws that protect informal workers lack practical enforcement mechanisms and are generally ineffective because informal workers lack employment contracts and awareness of their legal rights. Thai social security laws fail to provide informal workers with treatment of work-related accidents, diseases, and injuries; unemployment and retirement insurance; and workers' compensation. The article summarizes the differences in protections available for formal and informal sector workers and measures needed to decrease these disparities in coverage.

Asbestos Exposure among Mitering Workers.

The objectives are to compare the airborne asbestos concentrations resulted from mitering of abestos cement roof sheets by a high-speed motor and a hand saw, and to monitor whether other workers near the test sites are vulnerable to the fibers exceeding the occupational exposure limit. Four test cases were carried out and altogether 7 personal and 4 area air samples were collected. The NIOSH method 7400 was employed for the air samplings and analysis. Using the phase contrast microscopy, fiber counting was conducted under Rule A. The study showed that the fiber concentration medians for personal air samples gathered from the two tools were 4.11 fibers/cc (ranged: 1.33-12.41 fibers/cc) and 0.13 fibers/cc (ranged: 0.01-5.00 fibers/cc) respectively. The median for the area samples was 0.59 fibers/cc (ranged: 0.14-3.32 fibers/cc). Comparing each study case, the concentration level caused by the high-speed motor saw was more than twice that of the hand saw. According to the area samples, the workers nearby the test site are at risk from high exposure to asbestos.

Concentrations and size distribution of inhalable and respirable dust among sugar industry workers: a pilot study in Khon Kaen, Thailand.

There has been very limited information regarding bagasse exposure among workers in sugar industries as well as on health outcomes. The authors determined the occupational exposure of sugar industry workers in Khon Kaen to airborne bagasse dust. The size of the bagasse dust ranged from 0.08 to 9 µm with the highest size concentration of 2.1 to 4.7 µm. The most common size had a geometric mean diameter of 5.2 µm, with a mass concentration of 6.89 mg/m(3)/log µm. The highest mean values of inhalable and respirable dust were found to be 9.29 mg/m(3) from February to April in bagasse storage, 5.12 mg/m(3) from May to September, and 4.12 mg/m(3) from October to January. Inhalable dust concentrations were 0.33, 0.47, and 0.41 mg/m(3), respectively. Workers are likely to be exposed to high concentrations of bagasse dust and are at risk of respiratory diseases. Preventive measures, both in the form of engineering designs and personal protective devices, should be implemented.

A program for thai rubber tappers to improve the cost of occupational health and safety.

The purposes of this research were to determine the cost of occupational health and safety and work-related health problems, accidents, injuries and illnesses in rubber tappers by implementing a program in which rubber tappers were provided training on self-care in order to reduce and prevent work-related accidents, injuries and illnesses. Data on costs for healthcare, the prevention and the treatment of work-related accidents, injuries and illnesses were collected by interview using a questionnaire. The findings revealed that there was no relationship between what was spent on healthcare and the prevention of work-related accidents, injuries and illnesses and that spent on the treatment of work-related accidents, injuries and illnesses. The proportion of the injured subjects after the program implementation was significantly less than that before the program implementation (p<0.001). The level of pain after the program implementation was significantly less than that before the program implementation (p<0.05). The treatment costs incurred after the program implementation were significantly less than those incurred before the program implementation (p<0.001). It was demonstrated that this program raised the health awareness of rubber tappers. It strongly empowered the leadership in health promotion for the community.

Prevalence and risk factors of low back pain among Thai and Myanmar migrant seafood processing factory workers in Samut Sakorn Province, Thailand.

This study assessed the prevalence of low back pain (LBP) and investigated risk factors for LBP among seafood processing factory workers in Thailand including migrant workers. The subjects were Thai and Myanmar workers in the typical seafood processing factory. A cross-sectional study was carried out with a self-administered questionnaire. Prevalence of LBP, general characteristics, life style, and working condition were investigated. The associations between LBP and risk factors were estimated by multiple logistic regression models. Of 254 workers, 165 completed the questionnaire. Half of these workers were Thai, the others were from Myanmar. The point prevalence of LBP was 28.5%. Risk factors for LBP were age over 40 yr, poor health status, history of back injury, twisting posture at work, and slipping on wet floors. The results suggest that health promotion should focus on working conditions rather than individual life style in order to prevent LBP. Furthermore, greater attention to other risk factors such as history of back injury and perception of health status after regular health check up, especially in older age groups may be needed.

Blood lead level and cardiovascular risk factors among bus drivers in Bangkok, Thailand.

This study aimed to clarify the role of blood lead level (Pb-B) as one of the cardiovascular risk factors. To evaluate the cardiovascular risk the second derivative finger photoplethysmogram (SDPTG) was used. The subjects comprised of 420 male bus drivers in Thailand. The subjects' age ranged from 20 to 60 yr. Mean age (+/- standard deviation) were 41.6 (+/- 7.7) yr. Mean working years was 8.8 (+/- 6.8) yr. Pb-B ranged from 2.5 to 16.2 microg/dl with the mean Pb-B of 6.3 (+/- 2.2) microg/dl. The mean of aging index of SDPTG (SDPTG-AI) were -0.50 (+/- 0.30). The SDPTG-AI increases with age, Pb-B, smoking and alcohol consumption. There was significant correlation between Pb-B and SDPTG-AI after controlling for age, body mass index and lifestyle factors. These results suggest that Pb-B is possibly an independent cardiovascular risk factor for bus drivers exposed to lower level of lead.

A participatory model for improving occupational health and safety: improving informal sector working conditions in Thailand.

The purpose of this study was to evaluate the implementation of an Occupational Health and Safety Management Model for informal sector workers in Thailand. The studied model was characterized by participatory approaches to preliminary assessment, observation of informal business practices, group discussion and participation, and the use of environmental measurements and samples. This model consisted of four processes: capacity building, risk analysis, problem solving, and monitoring and control. The participants consisted of four local labor groups from different regions, including wood carving, hand-weaving, artificial flower making, and batik processing workers. The results demonstrated that, as a result of applying the model, the working conditions of the informal sector workers had improved to meet necessary standards. This model encouraged the use of local networks, which led to cooperation within the groups to create appropriate technologies to solve their problems. The authors suggest that this model could effectively be applied elsewhere to improve informal sector working conditions on a broader scale.

Health risk among asbestos cement sheet manufacturing workers in Thailand.

OBJECTIVE: To assess asbestos exposure and calculate the relative risks of lung cancer among asbestos cement roof sheet workers and to predict the incidence rate of lung cancer caused by asbestos in Thailand. MATERIAL AND METHOD: A cross-sectional study was conducted in four asbestos cement roof factories. Both area and personal air samples were collected and analyzed employing NIOSH method # 7400 and counting rule A for all procesess and activities. The time weight average exposures were calculated for each studied task using average area concentrations of the mill and personal concentrations. Then, cumulative exposures were estimated based on the past nation-wide air sampling concentrations and those from the present study. The relative risk (RR) of lung cancer among asbestos cement sheet workers was calculated and the number of asbestos related lung cancer case was estimated. RESULTS: The roof fitting polishers had the highest exposure to airborne asbestos fiber (0.73 fiber/ml). The highest average area concentration was at the conveyor to the de-bagger areas (0.02 fiber/ml). The estimated cumulative exposure for the workers performed studied-tasks ranged in between 90.13-115.65 fiber-years/ml while the relative risk of lung cancer calculated using US. EPA's model were 5.37-5.96. Based on the obtained RR, lung cancer among AC sheet in Thailand would be 2 case/year. CONCLUSION: In case that AC sheet will not be prohibited from being manufactured, even though only chrysotile is allowed, the surveillance system should be further developed and more seriously implemented. The better control measures for all processes must be implemented. Furthermore, due to the environmental persistence of asbestos fiber, its life cycle analysis should be conducted in order to control environmental exposure of general population.

Prevalence and management of diabetes and associated risk factors by regions of Thailand: Third National Health Examination Survey 2004.

OBJECTIVE: The aim of this study was to determine the prevalence of diabetes and impaired fasting glucose (IFG) and their association with cardiovascular risk factors and to evaluate the management of blood glucose, blood pressure, and cholesterol in individuals with diabetes by geographical regions of Thailand. RESEARCH DESIGN AND METHODS: With the use of a stratified, multistage sampling design, data from a nationally representative sample of 37,138 individuals aged > or = 15 years were collected using questionnaires, physical examination, and blood samples. RESULTS: The prevalence of diabetes and IFG weighted to the national 2004 population was 6.7% (6.0% in men and 7.4% in women) and 12.5% (14.7% in men and 10.4% in women), respectively. Diabetes was more common in urban than in rural men but otherwise prevalence was relatively uniform across geographical regions. In more than one-half of those with diabetes, the disease had not been previously diagnosed, although the majority of those with diabetes were treated with oral antiglycemic agents or insulin. The prevalence of associated risk factors was high among individuals with diabetes as well as those with IFG. Two-thirds of those with diabetes and concomitant high blood pressure (> or = 130/80 mmHg) were not aware that they had high blood pressure, and > 70% of those with diabetes and concomitant high cholesterol (total cholesterol > or = 6.2 mmol/l) were not aware that they had high cholesterol. CONCLUSIONS: The prevalences of diabetes and IFG were uniformly high in all regions. Improvements in prevention, diagnosis, and treatment of diabetes and associated risk factors are required if the health burden of diabetes in Thailand is to be averted.

A study of melatonin levels and stress in female shift workers.

The aim of this study was to determine the relationship between saliva melatonin and stress levels in Thai female shift workers. Five older (38.4 +/- 1.82) and five younger (21.4 +/- 0.55) female workers voluntarily participated in this study. All participants worked both morning and night shifts at a glass manufacturing factory. Saliva was collected every three hours at the workplace and at the subjects' houses to examine melatonin profiles. The Mann-Whitney U test and the Wilcoxon signed ranks test were used. There was a significant (p < 0.05) difference between melatonin levels in younger and older subjects when measured during the night shift at 19:00. Differences between melatonin levels during the morning and night shifts in the older group were significant at 07:00 and at 19:00 in younger subjects (p < 0.05). Normal stress and mild stress were found. No significant differences in melatonin levels were found between workers with normal and mild stress levels. The onset time of increasing saliva melatonin was at 19:00, both in women working the morning shift and in those working the night shift. Peak melatonin production occurred at 22:00 for the night shift in both groups. During the morning shifts, the peak times were at 04:00 and 01:00 (in the younger and older groups, respectively), usually between 02:00 and 04:00. These findings show that melatonin levels in female shift workers adapted according to the shift worked, especially in the older group. Health surveillance programs should therefore be established to prevent further negative health effects for female shift workers.

Occupational health education and collaboration for reducing the risk of lead poisoning of workers in a battery manufacturing plant in Thailand.

We provided occupational health education as training to all workers (N=31) and managers, and collaborated with them against reducing the risk of lead poisoning of workers at an assembly section in a battery manufacturing plant in Bangkok, Thailand in 2002. After occupational health education, many workers (80.6-100.0%) noticed and understood the toxicity of lead and the importance of protection against it. Many workers regularly wore long sleeved shirt and trousers, and used the appropriate mask all day long. They changed the attitude toward their work and improved personal hygiene, for example no smoking in the workplace, washing their hands by a detergent before drinking water or having lunch, and taking a bath after the work. They especially took off working clothes at an office outside the workplace and washed them everyday. The average blood lead level of the workers significantly (P=0.002) reduced from 32.7 microg/dl to 22.4 microg/dl, although airborne lead level in the workplace remained unchanged with before conditions. From these results occupational health education and collaboration between workers and managers were effective tools to reduce the risk of lead poisoning of workers in a battery manufacturing plant.

Lead exposure and blood lead level of workers in a battery manufacturing plant in Thailand.

This study was conducted in a battery manufacturing plant where lead was used in the processes of production, to survey the working conditions and safety behaviors, and to measure the airborne lead level contaminated in the workplace and the blood lead level of workers. The survey of working conditions showed that the workers were directly exposed to lead in sections e.g. grid casting, spreading, forming and polishing, assembly and special battery production sections. Some workers in these sections used a cotton mask to protect dust exposure, but most workers did not use any masks. High airborne lead level more than 0.2 mg/m3 was frequently measured in these sections. Geometric average of blood lead level slightly increased from 17.9 microg/dl to 22.3 microg/dl during 1998 and 2001. However, the geometric average of blood lead level dropped to 17.4 microg/dl in 2002. No workers had blood lead level above 60 microg/dl. Workers with different age groups had no significantly different average blood lead level. Workers whose duration of work was between 20-29 years had average blood lead level of 21.5 microg/dl. This group of workers had slightly higher blood lead level than those whose duration of work was 19 years or less, but with no significant difference. 21 subjects underwent annual health examination and exposure monitoring in 2002. There was no significant relation between airborne lead level and blood lead level.