非對稱提舉方式對於男性提舉能力之效應

Effects of Lifting Strategy on Asymmetric Lifting Capacity of Chinese Males

本研究旨在採用心理物理法來探討不同提舉方式及扭轉角度對於國人男性最大可承受提舉重量之效應。共甄選 8 位的男性大學生參與實驗。每位受試者必須執行七種不同的提舉作業，包括有二種提舉方式（先抬後轉（Lifting/Twisting，LT）及先轉後抬（Twisting/Lifting，TL）及三種扭轉角度（ 30o 、 60o 及 90o ）六次，及對稱式提舉作業一次（ 0o ，矢狀面） ，並收集受試者最大可承受提舉重量（Maximum Acceptable Weight of Lift，MAWL）和主觀知覺施力評量（Rating of Perceived Exertion， RPE） 。結果發現：1.不同提舉方式及扭轉角度對於最大可承受提舉重量具有顯著效應，先抬後轉之提舉作業大於先轉後抬之提舉作業，而由受試者所決定的 MAWL 值則隨著扭轉角度增加而降低；2.在提舉方式為先抬後轉時，受試者從對稱 0o 面到扭轉30o 、60o 和 90o 的 MAWL 分別下降 5%、10%及 12%左右，而在提舉方式為先轉後抬時，受試者從對稱 0o 面到扭轉 30o 、60o 和90o 的 MAWL 分別下降 12%、18%及 19%左右；3.提舉方式和扭轉角度對於身體各部位之 RPE 值均有顯著的差異，在提舉方式以先轉後抬之 RPE 顯著大於先抬後轉，且扭轉角度愈大，壓力愈大，身體各部位則以下背壓力最大。整體而言，本研究証實在提舉作業中，若不能使用對稱提舉方式來搬運時，先抬後轉之搬運方式比先轉後抬來得佳，其下背傷害也較小。

According to IOSH studies on refractory brick manufacturers, workers may be exposed to tridymite and cristobalite. The mass median aerodynamic diameter shows that they are thoracic particulate. Manufacturing processes of ceramics composed of mixing, molding, drying, glazing, and burning, similar to refractory brick manufacturing. This study focuses on the exposure of respirable particulate and crystalline free silica in ceramics manufacturing. The results show that 32% of the material samples contain crystalline free silica. If they are considered as the fourth category nuisance dust, compared to the PEL value of Taiwan labor regulation, 2.1% of the samples exceed the regulation limit. If they are considered as the second category dust, compared to the PEL value of Taiwan labor regulation, 18.8% of the samples exceed the regulation limit. For workers at different manufacturing lines the average personal respirable particulate exposure level, in descending order, is sanitation ceramic, daily use porcelain, ceramic materials handling , construction ceramic, industrial ceramic, art porcelain. In all processes of the ceramic manufacturing, the glazing worker has the highest average dust exposure (1.37 mg/m3). When using direct reading dust monitor, glazing process has the highest dust concentration as well. The survey of construction ceramic manufacturing result shows dust in all process zones and MMAD of crystalline free silica are in the range of respirable dust. The particle size distribution of respirable particulate and crystalline free silica indicates that crystalline free silica has a higher concentration of large particles. For personal sampling and portable particle counter, the process with the most serious exposure is in glazing, especially glazing spray.