- 學位論文
以微粒電移動度掃瞄分徑器量測咳嗽飛沫粒徑分佈之研究
The Study of Using SMPS to Measurement Size Distribution of Coughing Droplet
摘要
由人體所排呼出的飛沫可能帶有能傳染疾病之微生物。由於小於次微米之粒徑在文獻中顯示占了絕大部分。此研究的目的是建立健康個體所呼出小於次微米的飛沫粒徑分佈，並且去量測性別的差異對於咳嗽風速與飛沫濃度之比較。使用採樣袋收集飛沫，再同時以微粒電移動度掃描分徑器（Scanning Mobility Particle Sizer, SMPS）系統量測咳嗽飛沫，建立小於次微米之飛沫粒徑分佈。並且將實驗資料進行統計分析，以比較不同的年齡和性別對於粒徑分佈之差異。然後利用這些資料進一步去計算飛沫之蒸發時間，沉降距離及水平距離。 以SMPS 系統實驗結果顯示飛沫粒徑範圍分佈在從0.019〜0.35 μm，而約有80% 的咳嗽飛沫粒徑是在0.03 〜0.2 μm之間，大多數飛沫其粒徑是大於0.03μm；年齡層對於飛沫之粒徑分佈並無顯著之差異，性別的部份則是第2 類族群會受到飛沫粒徑影響而有差異，其餘並沒有顯著之差異。另外在風速計的數據顯示速度分佈範圍從0.13〜1.88 m/s；在這項研究過程中發現飛沫濃度有隨著咳嗽產生之風速而增加的趨勢；而在咳嗽風速與飛沫濃度方面皆是男性大於女性的。飛沫傳輸方面，於20℃、相對濕度（RH）為50％之環境下，粒徑為0.2 μm之飛沫推估其蒸發時間只需7.07×10-5秒，而在蒸發前之沉降距離僅有4.40×10-9公分，水平傳播距離則約為8.58×10-5公分，顯示咳嗽所產生之奈米飛沫，其運動範圍只侷限於產生源附近，且很快地蒸發成飛沫核；而飛沫核在空氣中傳播，會造成疾病擴散的可能性。很多傳染性疾病屬於次微米以下之粒徑例如SARS致病菌。因此藉由此研究可以進一步了解飛沫粒徑在小於次微米之分布情形。
並列摘要
Droplet exhaled from human may carry microorganisms capable of transmitting disease. As a result of the size be smaller than micron scale had been proven to occupy the great part of size distribution . The goal of this study was to establish the nano scale size of droplet exhaled by healthy individuals, and to compare the sexual differences of the coughing velocity and droplet concentration. Using sample bag to collect droplet. The droplets from human subjects performing coughing were measured by scanning mobility particle sizer (SMPS) system, and establish the droplet size distribution. Furthermore, these data were treated with statistical analysis, comparing the difference of different ages and sexual classification. Then computing the evaporation time, falling distances, horizontal traveling distances with some assumptions. The data of SMPS system showed the respiratory droplets ranged from 0.019 to 0.35 mm and 80% of droplets were between 0.03 and 0.2 mm. Most droplets were more than 0.03 mm. The droplets size were not remarkably difference in age and sexual classification, except for group 2 in sexual classification. The data of wind meter showed the velocity ranged from 0.13 to 1.88 m/s. In this study we found the droplet concentration will increase with coughing velocity. In the data of coughing velocity and droplet concentration, male’s is larger than female’s. In the environment of 20℃ and 50% relative humidity, it took only 7.07×10-5 seconds for 0.2 mm droplet to evaporate, and the falling distance was less than 4.40×10-9 cm, the horizontal traveling distance was about 8.58×10-5 cm. It showed the range of droplets produced by coughing was near the source, and evaporating to form droplet nuclei quickly. If droplet nuclei transmit in the environment, there will be the possibility of infection of diseases. Many infectious diseases belong to nano scale size such as SARS. Therefore this study could be understood its distribution in the smaller scale of droplet size.