熱環境暴露指標之改進研究

An Improved Index of Exposure in the Hot Workplace

本文針對台灣地區高溫作業場所進行熱環境監測所得資料？計算綜合溫度熱指數（WBGT）、熱應力指數（HSI）、修正有效感覺溫度（CET）之勞工熱暴露時量加權平均值，與各指標暴露閾值比較，發現這些指標之評估結果有其差異性。探究其原因，以風速、溫濕度條件及代謝熱等參數為重要之影響因素。本文以不同參數組合改良各熱暴露指標進行研究，結果顯示以風速、乾濕球溫度差兩項變數對於綜合溫度熱指數（WBGT）具有相當大的改良效果，且仍不會失去其原有易於量測之特性，因此將該兩項參數直接併入溫度熱指數公式作為本土化改良式熱暴露指標（IHEI）。

The environmental parameters in the hot workplaces in Taiwan were measured in this study. These data were used to evaluate the heat exposure time-weighted average values of The Wet Bulb Globe Temperature (WBGT), Corrected Effective Temperature (CET) and Heat Stress Index(HSI) on workers. Furthermore, these values were compared to the Threshold Limit Values (TLV) prescribed by three existing indices. The estimated results for these existing certain differences which are due to the air velocity, the humidity condition and the metabolic heat etc. To improve utility and localization of heat exposure indices, the modified parameter was tested in this study. We added the air velocity and the humidity condition items to the WBGT index. The new model, improved heat exposure index (IHEI), is quite reliabe and more accurate than the existing WBGT index. Meanwhile, the new model is also easy to evaluate the hot workplace.