矽甲烷是高科技產業使用的重要製程氣體，因矽甲烷與空氣接觸後具有自燃或延遲爆炸的特性，因此使用安全有特別的考量。供氣系統安全防護雖然可以預防或消減矽甲烷發生洩漏後所產生的危害，但如果能有效控制矽甲烷洩漏發生率，則可防止發生事故。除了供氣系統設備管線損壞造成的矽甲烷洩漏，人員進行鋼瓶換裝作業所發生的失誤動作亦為矽甲烷發生洩漏的原因之一，因此本研究藉由人為可靠度技術，計算鋼瓶換裝作業中可能發生的矽甲烷洩漏機率。本研究運用氣瓶櫃與Y-鋼瓶兩種類型的矽甲烷供氣系統標準作業程序，以刪減與合併的原則進行第一階段的處理，並藉由層級作業分析進行系統化的作業排序。第二階段處理則篩選關鍵的作業步驟，並將篩選後的關鍵作業步驟轉換為失誤描述且以PHEA的失誤類型進行分類，藉由HRA Event Tree計算空鋼瓶拆卸後與實鋼瓶安裝後兩階段鋼瓶更換作業所可能造成的矽甲烷洩漏機率，並判斷主要造成失效的情境。本研究評估的結果，氣瓶櫃作業以鋼瓶墊片未安裝為主要的失誤步驟，Y-鋼作業則為吹除次數未正確設定，因搬運鋼瓶時所發生的碰撞傾倒則為兩系統中共同的關鍵人為失誤因素。藉由本研究所建立的分析方法，可明確辨識影響作業失效的關鍵步驟，並防止因換瓶作業造成矽甲烷洩漏事件。 Silane is a special gas widely used in semiconductor, photovoltaic, and flat panel display manufacturing. Silane is pyrophoric but does not always ignite when leaked. The delayed ignition may result in explosion in a confined environment. Most silane accidents occur during gas cabinet cylinder change. Increased silane consumption increases the frequency of empty cylinder replacement and hence the silane release. Consequently, bulk silane gas supply system, with cylinders containing more than 250 liters of silane, has gradually replaced gas cabinet. Despite enhanced safety features of silane supply systems, human errors during cylinder change continue to be the main cause for silane accidents. This study is aimed to analyze human reliability in silane cylinder change process for both gas cabinet and bulk silane supply systems. Since the proposed human reliability assessment technique is based on the standard operating procedures of cylinder change, the assessment results can also be used to prevent human errors. Because of the fact that certain steps in the cylinder change Standard Operating Procedures involve no operator intervention, these procedures are regrouped. The first phase utilizes the Hierarchical task Analysis principle to delete and combine the original cylinder change procedures. The second phase further transfers the major procedures into error types. The Human Reliability Assessment Event Tree is then constructed based on the condensed version of the operating procedures. Results indicate that incomplete installation of the gasket is the major human error for the gas cabinet cylinder change process while incomplete purge is the most significant error for the bulk silane supply system. Safe handling of cylinders is critical in preventing silane leak in both systems.
