口罩佩戴密合度與微粒洩漏粒徑分布評估

Evaluation of Fit Factor and Particle Deposition due to Leakage of N95 Filtering Facepiece Respirators

陳依渟(Yi-Ting Chen)

指導教授 ： 賴全裕

中山醫學大學/健康管理學院/職業安全衛生學系/碩士(2020年)

https://doi.org/10.6834/csmu202000178

摘要

本研究以不同的密合度及呼吸流率組合來模擬勞工在靜止、輕度及中度工作中佩戴N95口罩時的情形，藉著微粒濃度的測定得到洩漏粒徑分布及洩漏率。並將三種不同款式的N95口罩做比較，分析勞工佩戴口罩的密合度及其呼吸快慢不同時對口罩洩漏率及洩漏粒徑的影響。
研究以台灣勞工標準人頭分別佩戴3M8210、3M8511及Champak F550C之N95口罩，連接呼吸模擬器，並將呼吸流率調整至15、30、55 L/min分別代表靜止、輕度、中度工作之呼吸型態，及使用TSI 8038 Portacount密合度測試儀，調整不同的密合度係數（Fit factor, FF）至10、30、50、100，再利用卡里遜噴霧器產生酒石酸鉀鈉（Potassium sodium tartrate tetrahydrate, PST）挑戰氣膠至測試系統中，同時以Fidas®Frog進行微粒粒徑分布監測。
實驗結果顯示：3M8210、3M8511、F550C三款口罩在呼吸流率15 L/min、密合度10，微粒洩漏之粒數中位數粒徑（count median diameter, CMD）分別為0.36微米、0.3微米、0.33微米，密合度100之CMD 都是0.28微米。此外，在呼吸流率55 L/min、密合度為10，三款口罩CMD分別為0.3微米、0.27微米、0.29微米，而密合度100時，三款口罩CMD皆為0.26微米。表示當密合度越大、呼吸流率越快時其洩漏粒徑也越小。
統計分析結果顯示，在總洩漏率部分，三款口罩不論呼吸流率為15、30、55 L/min，隨著N95口罩的密合度越高其洩漏率越低。三款口罩洩漏粒徑的比較，多數在3M8210對F550C 與3M8511對F550C有顯著差異，皆是碗型口罩與鴨嘴型口罩間的差異，推測其原因可能為臉部與N95口罩之貼合形狀有關。建議勞工佩戴口罩時，除需選擇適當尺寸外，仍要注意口罩與口鼻之間是否密合以達到最好的防護效果。

關鍵字

N95口罩 ； 口罩密合度 ； 洩漏率 ； 洩漏粒徑分布

並列摘要

In this study, the leakage rate and particle size distribution of N95 facepiece filtering respirator (FFR) under different conditions of workers at resting, light and moderate work were examined by adjusting the fit factor (FF) and breathing flow rate . In addition, we also investigated the leakage rate and particle size distribution of three types of N95 FFR in different conditions of the fit factor (FF) and breathing flow rate .
The testing system established for the experiment used 3M 8210, 3M 8511, and Champak F550C N95 FFR was worn by a standard manikin head model of Taiwan labor and connected to a breathing simulator with the breathing flow rate adjusted to 15, 30, or 55 L/min to represent resting, light, or moderate work breathing pattern, respectively. The fit factor of the mask was adjusted to 10, 30, 50, or 100 by using TSI 8038 Portacount Respirator Fit Tester. A Collison nebulizer was used to produce potassium sodium tartrate tetrahydrate challenge aerosol into the test system and the particles were assessed by using Fidas® Frog.
The results showed that the CMD of leakage particle size distribution of 3M8210、3M8511 and F550C was 0.36 µm、0.3 µm and 0.33 µm as FF was 10 under 15 L/min breathing flow rate, respectively ; CMD of 3M8210、3M8511 and F550C µm were all 0.28µm as FF was 100 respectively. In addition, CMD of leakage particle size distribution of 3M8210、3M8511 and F550C was 0.3 µm、0.27 µm and 0.29 µm as FF was 10 in 55 L/min, respectively ; CMD of 3M8210、3M8511 and F550C were all 0.26 µm as FF was 100, respectively. It showed the leakage particle size was decreased by increasing of FF and breathing flow rate.
Statistical results showed that the leakage rate of the three N95 FFR was decreased by increasing of FF in any breathing flow rate. In addition, a leakage particle size distribution significant difference between F550C to 3M8210 and F550C to 3M8511, that related to the shape of the N95 FFR. It may be due to the portion of the face that fitted the N95 FFR.
This study showed the leakage rate and particle size distribution of N95 FFR is related to FF and breathing flow rate. It may provide more effective protect effect by adjusting the fit factor (FF) and choosing the fit size of N95 FFR.

並列關鍵字

N95 respirator ； Fit factor ； Leakage rate ； Particle size distribution

參考文獻

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