中華民國內政部建築研究所中華民國內政部建築研究所

壹、研究緣起
2019年嚴重特殊傳染性肺炎(Coronavirus disease 2019, COVID- 19)讓全球受到顯著的衝擊影響，從全球國際政策與策略顯示，國際趨勢已將調整「建築與社區」之相關環境影響因子作為因應疫情衝擊與後疫情時期之政策與措施目標。新型冠狀病毒在個體間傳播包含許多因素，其中包括了建築的環境以及人類的行為。和其他呼吸道病毒傳播途徑相似，COVID-19的可能接觸途徑(1)手指接觸到受病毒污染的表面後再接觸到臉部；(2)吸入從咳嗽或說話呼出的病毒空氣粒子以及(3)咳嗽或說話呼出的病毒空氣粒子直接接觸到臉部。CFD 模擬了SARS-CoV-2在室內傳播的途徑並評估了空氣傳播的可能性，電腦模擬進行模擬細小的呼出液滴的傳播，比較了隨後感染源的室內位置和模擬的載有病毒的氣溶膠示踪劑的傳播情況。測量通風率使用示踪氣體濃度衰減法，從氣流動力學分析表明，感染分佈為與代表呼出的帶有病毒的氣溶膠遠程傳播的傳播模式一致(C. C. Wang et al., Science 373, eabd9149,2021)。SARS-CoV-2 病毒可能在通風量為 1.0 L/s/person (每人每秒) 的擁擠空間中通過空氣進行人與人之間的傳播。2020年3月世界衛生組織發表的報告中提到 SARS-CoV-2可能透過接觸、飛沫、空氣傳播、污染物、糞口、血源性、母嬰和動物對人等方式傳播。本計畫研究員曾提出公共廁所的空間設計、水路系統規劃、設備安裝、使用行為與維護管理的觀念錯誤或是瑕疵，造成使用者暴露在感染源擴散於空氣環境下，成為交叉感染的溫床(Lee & Tham, 2021)。因此，建築中(例如公共場所、醫療場所、飯店、旅館、娛樂場所或人們靠近的住宅)的環境因素，包括溫度、濕度、於病媒上的穩定性、通風和過濾系統等皆可能對感染有顯著影響。本計畫研究員曾調查111處公共廁所，發現公共廁所的設計、通風或設施不當，造成使用者的抱怨 (Lee et al., 2013)。
當帶原者處於該空間內，其飛沫、排泄物或是生物氣膠停留在空間中，因通風換氣不良，無法達到此換氣量，加上使用者行為與設施及材料的瑕疵，更易成為病毒交叉感染的溫床，尤其是空氣中含有 Omicron 變種病毒這種短時間接觸但具強大傳播力時。考量有效防疫的換氣量，是為本研究的重點。
貳、研究方法及過程
1.本研究的目的為蒐集現有關 COVID-19與其變種株之相關研究與了解其傳播特性來改善標章系統，確認及改善內容中能防止並降低建築中人與人傳播之風險，做到防範未來或許發生同樣情況之應變措施，最後擬定與國際脈絡接軌之探討可行性內容。
2.隨著綠建築與綠建材標章技術之成熟，加上對居住健康的品質要求，為達到改善環境與提升使用者健康與福祉之目的。蒐集及彙整各國、組織有關「國際永續評估體系」、「綠建材評估工具」、「健康建築」及「防疫建築」之相關研究等資料。
3.期在此基礎上探討創新綠建材評估之機制，經由相關研究方法之價值相互搭配共同使用，取得專家共識及獲得不同的建議做為決策方向之考量，並擬訂項目之基礎與後續理論發展之架構，提供政府政策工具擬定之參考。
4.本研究使用高階運算電腦進行計算動態流體力學(CFD)之數值模擬，進行不同條件之建築通風狀況分析，並提出適合通風量。
參、重要發現
1.室內空氣環境品質與生物氣膠傳播是懸浮於空中的微細物質，平時香菸燃燒後產生的煙霧、工廠或交通工具排放的 PM2.5或是各種呼氣動作(包括講話、呼吸等)產生的呼氣氣膠，都是典型的氣膠例子。
2.氣膠以極細微的懸浮微粒或液滴形式於空氣中散佈。透過分析發生於鑽石公主號等等室內場所的多起 COVID-19超級傳播感染事件，以及本文獻分析室內與室外感染比例(有超過95%的感染發生在室內環境)，皆指向氣膠傳播為主要傳播途徑。氣膠主要經由呼吸或講話產生，會隨著室內風環境，飄散的速率有明顯影響。
3.比起有症狀感染者咳嗽或打噴嚏生成的飛沫，更容易讓人掉以輕心。不像飛沫傳播必須與眼睛、鼻子或嘴巴的黏膜有直接接觸，對方只需吸入感染者所呼出仍保有傳染力的病毒氣膠，即會對肺部造成感染。另外，回顧多項研究也發現呼氣氣膠大部份來自肺部深處，顆粒雖小所攜帶的病毒量實際上卻更高。相對於大於100微米飛沫往往會在數秒內因為受重力主導而降落到地表或表面。傳統認知上往往誤以為氣膠傳播只發生在長程傳輸，實際上氣膠傳播在近距離更容易發生，因為離感染者距離愈近時，其呼出之病毒氣膠的粒子濃度更高。
4.現行的2公尺社交距離準則由於是根據飛沫及接觸傳播所設計的，並無法有效防範氣膠傳播。社交距離(Social distancing)是防止傳染性冠狀病毒(COVID-19)傳播的有效措施。
5.根據本研究團隊之研究，實施針對於醫療機構的通風換氣建議為正壓通風，進風量約為2倍，而施佩岑(居家廚房空氣品質改善策略之研究2022)對於居家汙染較高的廚房通風換氣建議亦為正壓通風，進風量約為1.5倍
6.本研究根據該結果與WHO的疫情改善方法(roadmap)對應提出建議醫療建設，居家、非居家之通風換氣量提出對健康技術規則設計施工篇第102條中之標準值，提出疫情加權推導，並將加權後之通風量與WHO之疫情改善建議之通風量，10L/S/person進行比對，並以CFD進行驗證，希能獲得妥善之建議，並在綠建築標準防疫篇中提出該加權係數。
表 1-1 102條建築技術規則增加倍數後之數值
 肆、主要建議事項
建議一
國內外換氣標準及法規之比較；立即可行建議
主辦機關：內政部營建署
協辦機關：內政部建築研究所
建築技術規則第102條法規比照世界衛生組織之通風換氣量，使用1.5倍增長率並作為防疫期間通風換氣標準，在增長1.5倍過後的換氣標準是必須要增加機械通風，而本研究建議新風換氣量需加入至建築技術規則102條法規。
建議二
使用ppm進行測量以防止過多耗能；立即可行建議
主辦機關：內政部營建署
協辦機關：內政部建築研究所
建議機械通風系統啟動使用ppm濃度浮動進行空間使用判別，此方式可確保人員是否在使用空間而不會造成過度能耗。
建議三
針對疫情期間住宅及非住宅空間換氣量係數增加以及空調系統引進新鮮外氣防疫措施；長期建議
主辦機關：內政部建築研究所
協辦機關：內政部
建議疫情期間住宅及非住宅換氣量增加:
1.住宅最小建議通風率10 L/s/person (EN 16798-1) 
2.非住宅最小建議通風率10 L/s/person (EN 16798-1) 
建議疫情期間住宅及非住宅空調系統防疫措施:
1.應謹慎使用帶循環裝置的暖氣和空調 
2.空氣應遠離進氣口、人和動物直接排到室外
3.應評估、維護和清潔具有循環裝置和暖氣、空調
4.作為污染物稀釋策略，室內空氣（隔離區內）應盡可能均勻改變

General Background Information
The severe special infectious pneumonia (Coronavirus disease 2019, COVID- 19) in 2019 has caused a significant impact on the world. From the perspective of global international policies and strategies, the international trend has adjusted the relevant environmental impact factors of "buildings and communities" as a response to the epidemic Policy and measure objectives in the shock and post-pandemic era. There are many factors involved in the transmission of the new coronavirus between individuals, including the built environment and human behavior. Like other respiratory viruses, the possible routes of exposure for COVID-19 are (1) touching a finger to a virus-contaminated surface and then touching the face; (2) inhalation of airborne particles of virus exhaled from coughing or talking; and (3) Airborne particles of virus exhaled by coughing or speaking come into direct contact with the face.
CFD simulated the route of SARS-CoV-2 transmission indoors and assessed the possibility of airborne transmission, and computer simulations were performed to simulate the transmission of fine exhaled droplets, comparing the subsequent indoor location of the source of infection with the simulated virus-laden air. Dissemination of sol tracers. Measuring ventilation rates using the tracer gas concentration decay method, from aerodynamic analysis indicated that infection distribution was consistent with transmission patterns representing long-range transmission of exhaled virus-laden aerosols (C. C. Wang et al., Science 373, eabd9149, 2021 ). SARS-CoV-2 virus may be transmitted airborne person-to-person in crowded spaces with a ventilation rate of 1.0 L/s/person (per person per second). According to a report published by the World Health Organization in March 2020, SARS-CoV-2 may be transmitted through contact, droplets, airborne, pollutants, fecal-oral, blood-borne, mother-infant, and animal-to-human transmission. The researchers of this project have pointed out that the space design, waterway system planning, equipment installation, use behavior and maintenance management of public toilets have erroneous or flawed concepts, which cause users to be exposed to the spread of infection sources in the air environment and become a hotbed of cross-infection ( Lee & Tham, 2021).
Therefore, environmental factors in buildings (such as public places, medical facilities, restaurants, hotels, entertainment venues, or residences where people are close), including temperature, humidity, stability on vectors, ventilation and filtration systems, etc. have a significant impact. Researchers in this project investigated 111 public restrooms and found that the design, ventilation or facilities of public restrooms were improper, resulting in complaints from users (Lee et al., 2013). When the carrier is in the space, the droplets, excrement or bioaerosol stay in the space, and the air exchange rate cannot be achieved due to poor ventilation. In addition, user behavior and defects in facilities and materials make it easier It becomes a breeding ground for virus cross-infection, especially when the air contains Omicron variant virus, which is short-term contact but has a strong transmission capacity. Considering the ventilation volume for effective epidemic prevention is the focus of this study.
Research Methods and Process
1.The purpose of this study is to collect existing research on COVID-19 and its variant strains and understand its transmission characteristics to improve the marking system, confirm and improve the content to prevent and reduce the risk of human-to-human transmission in buildings, to achieve Contingency measures to prevent the same situation that may occur in the future, and finally formulate the feasibility content of the discussion that is in line with the international context.
2.With the maturity of green building and green building material labeling technology, coupled with the quality requirements for living health, in order to achieve the purpose of improving the environment and improving the health and well-being of users. Collect and integrate relevant research data on "International Sustainability Assessment System", "Green Building Materials Evaluation Tool", "Healthy Building" and "Epidemic Prevention Building" from various countries.
3.On this basis, we will discuss the evaluation mechanism of innovative green building materials. Through the mutual matching and joint use of relevant research methods, we will obtain expert consensus and obtain different suggestions as considerations for decision-making directions, and formulate the foundation of the project and the framework for subsequent theoretical development. , to provide a reference for the formulation of government policy tools.
4.This research uses high-end computing computer to carry out the numerical simulation of computational dynamic fluid dynamics (CFD), analyze the ventilation status of buildings under different conditions, and propose the appropriate ventilation rate.
important discovery
1.Indoor air environmental quality and bioaerosol transmission are fine substances suspended in the air, such as the smoke produced by burning cigarettes, the PM2. Aerosols are typical examples of aerosols.
2.COVID-19 super-spreading infection events, as well as the analysis of the ratio of indoor and outdoor infections in this literature (more than 95% of infections occurred in indoor environments), all point to aerosol transmission as the main transmission route. Airgel is mainly produced by breathing or speaking, and it will have a significant impact on the rate of drifting with the indoor wind environment.
3.It is easier to take it lightly than the droplets produced by a symptomatic infected person coughing or sneezing. Unlike droplet transmission, which requires direct contact with the mucous membranes of the eyes, nose or mouth, the other party only needs to inhale the infectious virus aerosol exhaled by the infected person to cause lung infection. In addition, a review of multiple studies has also found that most of the exhaled aerosols come from the deep lungs, and the amount of virus carried by the particles is actually higher even though they are small. Droplets larger than 100 microns tend to fall to the ground or surfaces within seconds due to gravity dominance. Traditional cognition often mistakenly believes that aerosol transmission only occurs in long-distance transmission. In fact, aerosol transmission is more likely to occur at short distances, because the closer the distance to the infected person, the higher the particle concentration of the virus aerosol exhaled.
4.The current 2-meter social distance rule is designed based on droplet and contact transmission, and cannot effectively prevent aerosol transmission. Social distancing is an effective measure to prevent the spread of the contagious coronavirus (COVID-19).
5.According to the research of our research team, the recommended ventilation for medical institutions is positive pressure ventilation, and the air intake is about 2 times that of Spetzen (Research on Air Quality Improvement Strategies for Home Kitchens 2022) for kitchen ventilation with high home pollution. The recommended ventilation is also positive pressure ventilation, and the air intake is about 1.5 times
6.Based on the results and WHO's epidemic improvement method (roadmap), this study puts forward suggestions for medical construction, the ventilation volume of homes and non-homes proposes the standard value in Article 102 of the Design and Construction of Health Technical Rules, and proposes a weighted derivation of the epidemic situation. Compare the weighted ventilation volume with the ventilation volume recommended by WHO for epidemic improvement, 10L/S/person, and verify it with CFD, hoping to get a proper suggestion, and put forward the weighted in the green building standard epidemic prevention chapter coefficient.
Recommendations
Suggestion 1
Comparison of ventilation standards and regulations at home and abroad: immediate and feasible suggestions
Sponsor: Ministry of Interior Construction Administration
Co-organizer: Institute of Architecture, Ministry of the Interior
Article 102 of the Building Technical Regulations compares the ventilation rate of the World Health Organization, using a 1.5-fold growth rate as the ventilation standard during the epidemic prevention period. After the 1.5-fold increase, the ventilation standard must increase mechanical ventilation, and this study It is suggested that the fresh air exchange rate should be added to Article 102 of the Building Technical Regulations.
Suggestion 2
Measure in ppm to prevent excess energy consumption: immediate actionable recommendation
Sponsor: Ministry of Interior Construction Administration
Co-organizer: Institute of Architecture, Ministry of the Interior
It is recommended that when the mechanical ventilation system is started, use the ppm concentration fluctuation to judge the space usage.This method can ensure whether people are using the space without causing excessive energy consumption.
Suggestion 3
In the future, it will optimize the evaluation of airflow direction, external air quality and air conditioning energy consumption; long-term recommendations
Sponsor: Institute of Architecture, Ministry of the Interior
Co-organizer: Ministry of the Interior
In the future, the optimal evaluation will be carried out on the air exchange rate, airflow direction, external air quality and air conditioning energy consumption.
1.Airflow direction using CFD simulation
2.Air-conditioning energy consumption using energy analysis (eQUEST) to evaluate between ventilation and energy saving
3.The air quality of the external air volume can be investigated and given a substantive policy