臺灣博碩士論文加值系統

為了更客觀的判斷呼吸防護具與使用者臉部是否緊密貼合，美國職業安全衛生署(Occupational Safety and Health Administration, OSHA) 於2006年公布定量密合度測試法。其中最為廣泛應用的環境氣膠凝核計數法(Ambient Aerosol Condensation Nuclei Counter, CNC) 乃利用TSI公司所生產的PortacountTM，針對不同動作下口罩外與口罩內濃度進行採樣，計算出該呼吸防護具之密合係數(FFportacount)。然而，研究結果發現，因微粒濃度本身於面體內無法均勻混合，Portacount將抽到更多乾淨空氣；並且一部份微粒受到呼吸道沉積作用，使得測試的密合度值結果會高估真實密合的情形。因此，本研究將針對不同條件下讀值的高估情形以及相對應可能的修正方向提出相關建議。
本研究在定流量情形下(1 - 50 lpm)，量測洩漏管道與面體壓降對流量的關係，並藉由總流量與毛細管流量之比值，推算出只考慮吸氣階段氣流分配所計算出的真實密合度值(FFtrue)，因不受微粒沉積的影響，應較能反映真實洩漏的情況。實際進行密合度量測時，將使用100ppi海綿以模擬人體肺部微粒沉積情形，面體後端連接呼吸模擬器，前端則連接PortacountTM微粒採樣儀器，用以比較儀器量測值相對於真實密合度之準確度。在調整不同測試參數如呼吸模擬器潮氣容積(0.5 – 1.25 L)、呼吸頻率(3 - 30 bpm) 、面體洩漏管道直徑(1.0 - 1.5 mm)與肺部沉積(有無置入海綿)，結果發現PortacountTM讀值皆會高估真實密合度值約2 - 3倍，其原因為呼吸道沉積與面體內微粒混合不均勻作用，導致採樣管採到更多經過濾材的乾淨空氣，進而稀釋微粒濃度，使密合度上升；另外，在呼吸過程中，部分微粒也會沉積於呼吸管道內，同樣使得密合度上升。因此，從實驗結果而言，由於上述兩種作用影響，導致PortacountTM測試結果並無法反應面體真實佩帶時的洩漏情形。
本研究針對現行定量密合度測試方法，提出以下建議：取採樣時間最高濃度值計算出的最小密合度(FFmin)，其值較接近真實密合度值，將更能代表面體佩帶實際洩漏之情形，也較為保守。

The OSHA promulgated a quantitative fit test (QNFT) to ensure the respirator provides a satisfactory seal between the contaminated area and the wearer, and to check if the respirator properly be donned prior to initial use. The fit factor (FF) is determined by the ratio of particle concentration outside (Cout) and inside (Cin) the respirator. However, the result was found that the Portacount measurement might overestimate compared to the real fitting condition due to the effect of incomplete air/agent mixing in the respirator facepiece.
In this work, investigation of the fit factors was divided into three phases: (1) foam penetration test, (2) experimental testing using constant flow rate, and (3) simulation tests using a breathing machine (combination of tidal volume and breathing frequency). To simulate leakage on the respirator, capillaries with 1.5 mm in length with different diameters (1.0 -1.5 mm), were inserted at the place of nasal between the respirators the wearer’s face. The ratio of total flow to leak flow was considered the “true fit factor”.
In Phase 1, foam penetration test was conducted in order to fit the International Commission on Radiological Protection (ICRP) deposition model to simulate the lung deposition effect. A scanning mobility particle sizer (SMPS, model 3080, TSI Inc.) and an aerodynamic particle sizer (APS, model 3321, TSI Inc.) were used in this study. In Phase 2 of the study the pressure drop corresponding to the leakage and filter flow rates at the constant flow rates of 1-50 L/min were measured, which then used to assess the amount of leakage during different breathing pattern. In Phase 3, the effects of breathing pattern on in-mask particle concentration during fit testing were investigated. The values and correlation for FFt were obtained by the experiment results in Phase 2 and Phase 3.
The result shows the foam (α = 0.03, df = 36µm) with the thickness equals to 50 mm and the face velocity equals to 100 cm/s was good-fitted to the ICRP deposition model. For the breathing simulation experiment, it was shown that the fit factor of N95 and N100 were found to be overestimated compared to the FFt because the filtered air was partly sampled during inspiration phase by sampling tube which might dilute the particle concentration inside the facepiece. In addition, the fit factor might be more overestimated by Portacount when in the high breathing flow rate because of the flow distribution ratio through filter to the leakage increases. Therefore, it was concluded that the FF measured by Portacount might not represent the worst cases.
In this study, the suggestion for the current quantitative fit test method is proposed: the FFmin calculated from the highest particle concentration during the sampling time, which the value is closer to the FFt at the low ventilation breathing flow, will be better and more accurate to represent the real leakage condition compared to the Portacount measurement.

序言…………………3
第一章…………………5
第二章…………………50

第一章目錄…………………6
表目錄………………… 7
圖目錄…………………8
中文摘要…………………9
Abstract…………………10
一、研究背景與目的…………………12
1.1研究背景…………………12
1.2研究目的…………………13
二、 文獻回顧…………………13
2.1呼吸防護具洩漏來源與密合度…………………13
2.2定量密合度測試方法探討…………………15
2.3呼吸道微粒沉積效應…………………16
三、 研究方法…………………17
3.1海綿穿透率測試…………………17
3.2定流量測試之FFt與密合係數…………………18
3.3呼吸模擬器測試…………………18
四、 結果與討論…………………19
4.1 PortaCountTM測試儀校正與定量密合度實驗參數測試…………………19
4.2環境定量密合度測試法高估原因探討…………………20
4.2.1呼吸道沉積效應模擬…………………21
4.2.2微粒不均勻混合效應…………………22
4.2.3 呼吸道沉積與不均勻混合對於密合度高估之貢獻…………………23
4.3不同呼吸條件下FFcpc, FFmin 與 FFt之影響探討…………………24
五、 結論與建議…………………27
六、 參考文獻…………………28
表目錄
表一、微粒定量密合度測試法 (CPC)與負壓測試法 (CNP)之密合度讀值比較…………………30
表二、實驗參數表…………………31
圖目錄
圖一、微粒穿透率測試系統…………………32
圖二、定流量與循環流量之定量密合度測試系統…………………33
圖三、海綿穿透率曲線與ICRP模型曲線擬合…………………34
圖四、吸氣與吐氣階段之面罩內氣流分配…………………35
圖五、定量密合度測試儀延遲時間校正…………………36
圖六、口罩內微粒濃度達穩定時間與呼吸量之關係…………………37
圖七、(a) N95、N100口罩與(b) 1、1.5 mm毛細管壓降與流量之關係圖…………………38
圖八、密合度測試時之壓力變化與密合度計算…………………39
圖九、操作呼吸模擬器下之N100口罩內微粒濃度變化…………………40
圖十、操作呼吸模擬器下之彈性橡膠半面罩內微粒濃度變化…………………41
圖十一、操作呼吸模擬器下之N95口罩內微粒濃度變化…………………42
圖十二、不均勻混合與呼吸道沉積效應高估密合度之貢獻比例…………………43
圖十三、N95口罩內微粒濃度和最小密合度(FFmin)與呼吸頻率之關係…………………44
圖十四、N95口罩內微粒濃度和最小密合度(FFmin)與潮氣容積之關係…………………45
圖十五、使用N100口罩進行密合度測試時之密合係數…………………46
圖十六、使用N95口罩進行密合度測試時之密合係數…………………47
圖十七、使用彈性橡膠半面罩(P100濾棉) 進行密合度測試時之密合係數…………………48
圖十八、N95、N100口罩與彈性橡膠半面罩FFcpc與FFmin之高估情形…………………49

第二章目錄…………………51
表目錄…………………52
圖目錄…………………53
中文摘要…………………54
英文摘要…………………56
一、研究背景與目的…………………59
1.1研究背景…………………59
1.2研究目的…………………60
二、文獻回顧…………………61
2.1呼吸防護具洩漏來源與密合度…………………61
2.2定量密合度測試方法探討…………………63
2.3濾材過濾機制…………………64
2.4光學粒徑計數儀探討…………………67
2.5光學粒徑計數儀應用於定量密合度測試法…………………68
三、研究方法…………………69
3.1密合度實驗系統建立與測試…………………69
3.2光學粒徑分徑儀與氣膠凝核計數儀比較研究…………………69
3.3 N95過濾面體穿透率測試…………………70
四、 結果與討論………………… 71
4.1儀器反應時間與面體內濃度穩定時間…………………71
4.2光學粒徑分徑儀密合度與粒徑之關係…………………72
4.3不同呼吸條件與FFOPS, FFmin and the FFt之影響探討…………………72
五、 結論與建議………………… 74
六、 參考文獻…………………76
表目錄
表一、ANSI公布之新密合度方法檢驗標準…………………77
表二、實驗參數表…………………78
圖目錄
圖一、定量密合度測試系統…………………79
圖二、N95濾材穿透率實驗系統圖…………………80
圖三、OPS與CPC儀器反應時間…………………81
圖四、不同儀器量測N100口罩內微粒濃度達穩定之時間…………………82
圖五、OPS量測到面罩內外之微粒濃度與密合度…………………83
圖六、OPS與CPC量測N100口罩內微粒濃度與呼吸頻率之關係…………………84
圖七、使用N100口罩進行密合度測試時之密合係數…………………85
圖八、使用N95口罩進行密合度測試時之密合係數…………………86
圖九、N95穿透率曲線 (n = 10)…………………87
圖十、使用彈性橡膠半面罩(P100濾棉)進行密合度測試時之密合係數…………………88
圖十一、N95、N100口罩與彈性橡膠半面罩FFops與FFmin之高估情形…………………89

Aitken, R. J., Vincent, J. H., Mark, D. (1993). Application of Porous Foams as Size Selectors for Biologically Relevant Samplers. Applied Occupational and Environmental Hygiene 8:363-369.
Anderson, J. O., Thundiyil, J. G., Stolbach, A. (2012). Clearing the Air: A Review of the Effects of Particulate Matter Air Pollution on Human Health. Journal of Medical Toxicology 8:166-175.
AS/NZS (2012). Australian and New Zealand Standard. Respiratory protective devices.
Burnis, R. P. (1991). A Comparison of fit factors determined by an aerosol method and a dynamic negative pressure method
Crutchfield, C. D., Murphy, R. W., Ert, M. D. V. (1993). A Comparison of controlled negative pressure and aerosol quantitative respirator fit test systems by using human subjects. American Industrial Hygiene Association Journal 54:10-14.
Crutchfield, C. D., Park, D. L., Hensel, J. L., Kvesic, M. K., Flack, M. D. (1995). Determinations of Known Respirator Leakage Using Controlled Negative Pressure and Ambient Aerosol QNFT Systems. American Industrial Hygiene Association Journal 56:16-23.
Curtis, L., Rea, W., Smith-Willis, P., Fenyves, E., Pan, Y. (2006). Adverse health effects of outdoor air pollutants. Environment International 32:815-830.
Funke, J. (2000). A Comparison study of the overall fit factors between the portacount and the fit tester 3000, Safety, Health and Industrial Hygiene Department
Montana Tech of The University of Montana.
Graffeo, J. B. (1992). The classification of respirator fit as determined by an aerosol method and a negative pressure method.
Hinds, W. C. (1999). Aerosol Technology: Properties, Behavior, and Measurement of Airborne Particles. .
Holton, P. M. and Willeke, K. (1987). The Effect of Aerosol Size Distribution and Measurement Method on Respirator Fit. American Industrial Hygiene Association Journal 48:855-860.
ICRP (1979). Limits for Intakes of Radionuclides by Workers., the International Commission on Radiological Protection.
ICRP (1994). Human Respiratory Tract Model for Radiological Protection.
Lei, Z., Yang, J., Zhuang, Z., Roberge, R. (2013). Simulation and evaluation of respirator faceseal leaks using computational fluid dynamics and infrared imaging. Journal of occupational and environmental hygiene 9:46-58.
Li, N., Hao, M., Phalen, R. F., Hinds, W. C., Nel, A. E. (2003). Particulate air pollutants and asthma: A paradigm for the role of oxidative stress in PM-induced adverse health effects. Clinical Immunology 109:250-265.
Liu, B. Y. H., Lee, J.-K., Mullins, H., Danisch, S. G. (1993). Respirator Leak Detection by Ultrafine Aerosols: A Predictive Model and Experimental Study. Aerosol Science and Technology 19:15-26.
Myers, W. R., Allender, J., Plummer, R., Stobbe, T. (1986). Parameters that Bias the Measurement of Airborne Concentration Within a Respirator. American Industrial Hygiene Association Journal 47:106-114.
NIOSH (1995). Guide to Selection and Use of Particulate Respirator Certified under 42 CFR 84.
OSHA (1998). Rsepiratory Protection Standard (29 CFR 1910.134).
Rengasamy, S., Miller, A. T., Eimer, B. C. (2011). Evaluation of the filtration performance of NIOSH-approved N95 filtering facepiece respirators by photometric and number-based test methods. Journal of occupational and environmental hygiene: 23-30.
Rostami, A. A. (2009). Computational Modeling of Aerosol Deposition in Respiratory Tract: A Review. Inhalation Toxicology 21:262-290.
Wu, B., Leppänen, M., Yermakov, M., Grinshpun, S. (2017). Evaluation of a New Instrument for Aerosol Quantitative Fit Testing.
Wu, B., Leppänen, M., Yermakov, M., Grinshpun, S. (2018). Utility of an Optical Particle Counting Instrument for Quantitative Respirator Fit Testing with N95 Filtering Facepiece. Journal of the International Society for Respiratory Protection 35.
Yang, K.-J. (2017). Improvement of Quantitative Fit Testing Methods Using Ambient Aerosols.