半導體及光電業的VOCs濃縮轉輪維修保養作業危害辨識與風險管理

Abstract

半導體及光電業生產技術複雜性高，在製程上常需使用具有著火性、可燃性、高度毒性、腐蝕性等危害性化學物質。VOCs濃縮轉輪設備常用於控制此類VOCs氣體的排放。為了有效防止在處理過程中含VOCs之廢氣洩漏至大氣中而污染週遭之環境，因此濃縮轉輪常設置於密閉之箱體內，當系統停機後進行維修保養作業時，從業人員必須進入箱體內進行各項檢查與零件更換工作。因此除了會有與有害物接觸之可能性外，作業人員同時必須面臨局限空間作業、缺氧危險作業等高風險之作業型態，其潛在之危害風險不可忽視值得在本研究中探討。 本研究案例以國內某承攬半導體及光電業VOCs濃縮轉輪維修保養公司為分析對象，應用作業安全分析（Job Safety Analysis, JSA）技術，於VOCs濃縮轉輪維修保養作業過程中所涉及之人員、設備等進行危害辨識與分析，再以NSCA Risk Score Calculator計算獲得從業人員潛在之職業危害風險等級，以期提升作業安全與降低風險之績效。另外本研究也使用SPSS for Windows統計軟體，對個案公司從業人員進行健康檢查結果之t 檢定（t-test）和卡方檢定（Chi-Square tests）分析，探討有從事與無從事此項作業之人員在健康檢查方面有無顯著差異。研究結果顯示，個案公司之VOCs濃縮轉輪維修保養作業主要的危害類型屬物理性危害，佔51項總危害分類數的54%，其次依序為化學性危害佔22%，其他種類危害佔14%，人因工程性危害佔10%。作業風險等級分佈由高至低依序為中等風險，佔26項總關鍵性操作步驟數的42%，低度風險佔35%，非常高風險佔19%，稍高風險佔4%。評估結果顯示，屬於非常高風險之作業主要為需進入轉輪箱體內作業之工作項目，如VOCs濃縮轉輪檢查及清洗、氣密性檢查及灑水系統維修保養等作業。在健康檢查結果的卡方檢定方面，本研究發現無論在尿液、血液、肝功能、腎功能、血脂肪及血糖方面，控制組及暴露組皆無顯著的差異，此結果意味著VOCs濃縮轉輪維修保養作業人員並未受到明顯的危害。

The production processes of the semiconductor and optoelectronics industries are complicated and various hazardous chemicals with flammability, combustibility, toxicity and corrosiveness are used. The VOCs rotor concentrators are normally used to control the emissin of these exhaust gases. The rotor concentrators are placed in an airtight box in order to prevent the leaking of VOC gases to the ambient atmosphere. Maintenance engineers must get into the airtight box to conduct various check-ups and change the parts when the VOCs treatment system is shut down for the preventive maintenance. Besides contacting with hazardous materials, the pesonnels will also work in confined and oxygen-deficient space which poses high risks. It is worthwhile for this study to investigate the potential risks during the maintenance the rotor cncentrators. This study used a local company that conducts the preventive maintenance of the VOCs rotor concentrators in semiconductor and optoelectronics industries as an example. The Job Safety Analysis (JSA) method was applied to identify and analyze hazard factors for staffs, equipments that involved in the processes. The NSCA Risk Score Calculator was then used to evaluate the degree of the risks to improve the safety in operation and reduces the risks. In addtiion, the SPSS statistical software was used to conduct the t-test and Chi-Square tests for the results of the health examination of the personnels. The results show that 51 major hazards in the maintenance of VOCs rotor concentrators include the physical hazards (54%), followed by the chemical hazards (22%), other kinds of hazards (14%) and ergonomic hazards (10%). The percentage of the risk scores of 26 key operation processes is 42% for the moderate risk, 35% for the low risk, 19% for the very high risk, and 4% for the somewhat high risk. This results show that the very high risk jobs are related to the operations in the airtight box. For example, the inspection and washing of VOCs rotor concentrators, the inspection of gas tightness and the maintenance of the sprinkling water system. The Chi-Square tests of the health examination results show that no significant differences exisit in urinary, blood, liver function, kidney function, blood fat, blood sugar between the control and the exposure groups. It indicates that there are no significant riskes for the personnels working in the maintenance of the VOCs rotor concentrators.