A research project was conducted to study work-related musculoskeletal disorders (MSDs) at a die-casting plant in Korea. The project was consisted of 4 main parts; education on the topics of MSDs for all workers, symptom survey, medical check-up, investigation of MSD risk factors. The result of symptom survey showed that 89.5% of the respondents complained pains on at least one part of the body. After cross-sectional analysis of various information and risk factors based upon NIOSH criteria, 83.3% of respondents were considered as active health surveillance level 1, and 16% of the respondents were considered as active health surveillance level 2 those are at high risk of having MSDs based upon a criteria developed by Institute of Labor Science at University of Incheon. Also the result of medical examination by a industrial medicine MD showed that 41workers(44.1%) out of 93 workers examined were considered as MSD patient group at moderate level, and 10 workers(10.8%) were considered as MSD patient group at relatively high level that require certain level of medical treatment and ergonomics interventions for their workplace. The analysis of the work environment using various ergonomic investigation techniques revealed that repeated awakard postures(50%) and highly repatitive task(37.5%) were two most contributing risk factors for the on-set of MSD at this work site followed by handling of heavy object(8.3%), and vibration(4.2%).
Concrete with a pore solution of pH 10-12 is less alkaline than sound concrete but would still produce a strong color hange with phenolphthalein indicator. It therefore follows that the indicator test is likely to underestimate the depth to which carbonation has occurred. The indicator has not changed color near the top and bottom surfaces, suggesting that these near-surface regions are carbonated to a depth of at least 3 mm from the top surface and 5 mm from the lower surface. Where the indicator has turned purple - the center of the slab - the pH of the concrete pore fluid remains high (above 8.6, probably nearer 10).. Based on the above technical background, this study was devoted to examine the depth analysis of carbonated concrete quantitatively.