呼吸防護計畫濾毒罐／匣可使用時間之推估技術

當淨氣式呼吸防護具（Air Purifying Respirator, APR）使用濾毒罐／匣做為濾除氣狀有害物的濾材時，會因濾材達到飽和卻未更換，致無法達到保護佩戴者之目的。常理來說，濾毒罐／匣之可使用時間（Service time）應由實驗室測試，但其受成本考量，於實務面執行具有難度。對此，臺灣「呼吸防護計畫技術參考手冊」要求淨氣式呼吸防護具應具備認證合格之濾罐更換指示計（End of Service Life Indicator, ESLI），否則雇主需自行以經驗法則（Rule of thumb）計算濾毒罐／匣之可使用時間。然而，目前市售含有ESLI濾毒罐／匣僅屬少數，且美國職業安全衛生署（Occupational Safety and Health Administration, OSHA）認為，經驗法則不能做為唯一決定可使用時間的方法，又加上濾毒罐／匣製造商視其產品組成特性為商業機密，故事業單位如何於有限的資訊中推估濾毒罐／匣之可使用時間，進而落實濾毒罐／匣之更換，實有探討之必要性。本研究旨在釐清事業單位目前於呼吸防護計畫之執行現況，並蒐整文獻與參考美國OSHA之方法，建立濾毒罐／匣可使用時間之推估技術，繼而於5家事業單位嘗試推廣應用，並以問卷調查其推廣應用後之看法。研究結果顯示，呼吸防護具更換是呼吸防護計畫中執行程度把握最低之項目，且事業單位通常依製造商之建議定期進行更換。此外，事業單位對本研究所建立技術之推估結果可接受，但對推估方法之執行仍需要技術協助，及單位主管之經費支持。

關鍵字

呼吸防護具；濾毒罐／濾毒匣；可使用時間；呼吸防護計畫

並列摘要

When an Air Purifying Respirator (APR) uses a canister/cartridge as a filter to remove gaseous harmful substances, it can fail to protect the wearer if the filter material becomes saturated and is not replaced. Ideally, the service time of canister/cartridge should be determined through laboratory test. However, laboratory test is hard to implement due to cost. In response, Taiwan's respiratory protection program requires air purifying respirator should contain a certified End of Service Life Indicator (ESLI). If ESLI is not provided, employers are required to calculate the service time of canister/cartridge based on the rule of thumb. Currently, only few canisters/cartridges are known with ESLI. Moreover, the U.S. Occupational Safety and Health Administration (OSHA) suggests that the rule of thumb should not be considered as the sole method for determining the service time. In particular, many respirator manufacturers regard the composition of their products as confidential information. Therefore, developing techniques for predicting appropriate service time for canister/cartridge with limited information become a critical issue. This study first aims to clarify the implement status of the respiratory protection program currently conducted in the industry. Then, the technique for estimating the service time of canister/cartridge was established based on the literature review, and methods from the U.S. OSHA. This developed technique then applied to five industries, and questionnaire was used to survey their opinions. Results indicate that industries have the least confidence in managing the replacement of respirator, and most of industry change respirator based on manufacturers' recommendations. Additionally, the application of the developed techniques to five industry suggests that the obtained the service time result is acceptable. However, they still require assistance with the application of the developed technique, and budget supports from employers.