鋁業製造廠為高溫作業環境，本文為測定與評估鋁錠煉爐廠之高溫環境指標( WBGT,HSI,AET)，於其周圍選擇七處測點，量出五項重要之環境參數，包括乾球溫度、黑球溫度、濕球溫度、自然濕球溫度及風速。測量結果乾球溫度分佈於30-35℃、相對濕度分佈於75-85%之間。依其作業流程計算問加權平均代謝熱為150仟卡/時，時間加權平均綜合溫度指數為31.7℃，與1972年NIOSH標準之連續型工作閾限值( 31.2℃)比較，顯示長期暴露於此環境，容易引起熱危害。同時依據熱平衡方程式預測不同工作負荷及風速下之各項指數變化，發現風速在0.2至3.0米/秒之間時，身體最大排汗量( Emax)顯著增加、身體需要蒸發熱( Ereq)僅略增些，HSI可明顯降低，此表示作業環境之通風設施稍加改進，便可顯著減低熱危害程度。 Aluminum factory is a place of hot working environment. It could lead to the heat hazards if one exposes himself to these areas for a long term. In this study, Five import-ment environmental parameters such as dry buld, black globe, psychrometric web buld, natural buld temperature, and air velocity are measured on seven test locations in order to assessment and evaluation of hot environmental indices (WBGT, HSI, AET) in an aluminum smelting plant. The dry temperature is between 30˚and 35℃ and the relative humidity is between 75 and 85%, in this working environment. According to the work sequence and time of workers, the time weighted average of metabolic heat and WBGT are about 150 kcal/hr and 31.7℃ respectively. Therefore, in comparison with the threshold limit value of 1972 NIOSH standard at continuous work (31.2℃), heat strain will happen. Meanwhile, by calculation of the heat balance equation, variety of heat stress indices are predicted under different workloads and air velocities. With the great increase of Emax but the slight in-crease of Ereq while air velocity chan8es from O.2 to 3.O m/s, HSI will decrease obviously. Thus, the level of heat strain can reduce by improvement of ventilation.
