The Establishment for the Early Warning Scheme of Fine Particulate Matters (PM2.5) Hour Value

• Main Authors: Da-Yong Jian, 簡大詠
• Other Authors: Chao-Heng Tseng
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/ra3zf5

碩士 === 國立臺北科技大學 === 環境規劃與管理研究所 === 102 === International Agency for Research on Cancer (IARC) of World Health Organization classified particulate matters as Class 1 carcinogen. People, especially elderly citizens and children, are advised to refrain from outdoor activities when the PM2.5 concentration is getting higher. The United States issues early warning PM2.5 24-hr average based on Air Quality Index (AQI) hourly value. As for Japan and Taiwan, they adopted another health warming system for PM2.5 pollution. They issue early warning PM2.5 daily average value based on 5 to 7 hour average value. This study investigates the differences between the two system mentioned above based on the literatures and the air quality monitoring data. The target is to meet Taiwan PM2.5 air quality standard 35μg/m3 as well as public health impact 55 μg/m3 in the United States. The PM2.5 air quality standard (NAAQS) in the US is based on a 24-hr average. However, most government agencies use continuous PM2.5 monitors, which provide hourly averages. The question arises about how to get the most meaningful 24-hr average from all these 1-hr values. After discussions, the current AQI for PM2.5 in the US is defined as the most recent 12-hr average combined with the most recent 4-hr average. In this study, we looked for alternative method to adjust this calculation formula through regression analysis and proposed the most recent 1-hr instead of the most recent 12-hr average. This adjusted method provided an effective indicator of air quality. We think it is more suitable for Taiwan. In order to apply one-hour concentration of PM2.5 for a warning indicator, we proposed three different types of warning scenarios as follows: the fixed-time warning (issuing a warning based on the concentration averages from 0 a.m. to 7 a.m. every morning at 8 o’clock), the hourly concentration warning (issuing a warning based on the hourly concentration directly) and the probability of exceedance warning (issuing a warning when the concentration level exceed a given value by 5 times). According to our findings, we can get the better results on air quality warning if we could combine any two of these scenarios. Meanwhile, the study proposed 2 different advisories, giving people the opportunity to reduce their exposure, when ambient PM2.5 concentration is equal to 35 μg/m3 and 55 μg/m3 respectively.