Optical Aerosol Spectrometer (OAS) and dry aerosol generator (DAG) for COVID-related research

在新冠肺炎大流行期间，大多数当局都专注于通过建议洗手、表面消毒和2米物理距离来减少SARS-CoV-2(冠状病毒)的接触和飞沫传播，而很少关注SARS-CoV-2通过空气传播的可能性。然而，最近美国疾病控制中心(CDC)和ASHRAE的声明表明了RTI拨款和我们的COVID研究的紧迫性，以量化和减少暖通空调系统中空气传播的病原体传播。 ASHRAE：“SARS-CoV-2通过空气传播的可能性很大，因此空气中接触病毒的情况应该得到控制。改变建筑操作，包括供暖、通风和空调系统的操作，可以减少空气中的暴露。 疾控中心：“有几个证据充分的例子表明，SARS-CoV-2似乎是通过很长的距离或时间传播的。” 拟议的光学气溶胶光谱仪(OAS)和干式气溶胶发生器(DAG)将使我们能够产生气溶胶，并测量影响气溶胶传播的关键参数(即气溶胶颗粒的大小、浓度和运动)。虽然感染COIVD-19病毒所需的确切病毒剂量尚不清楚，但感染流感的人每小时会产生约2000个传染性气雾滴，在咳嗽、打喷嚏和唱歌时甚至会产生更多。这些气溶胶可以传播的距离取决于它们的大小和环境空气的速度。虽然冠状病毒本身(0.1微米)可能会在空气中停留数天，但呼出的含有体液和冠状病毒的气溶胶预计为1至5微米，并可能在空气中停留数小时(例如，3微米颗粒将以1米/小时的速度沉降，自然室内气流可能会将气溶胶输送近100米)。 新冠肺炎疫情提高了公众对建筑物室内空气质量重要性的认识。加拿大人90%以上的时间在室内度过，每天吸入15,000 L(17公斤)的空气，远远高于我们每天摄入的食物(~2公斤)和水(~2 L)。瓶装水强制要求标签标明含量和纯度，而我们呼吸的空气被认为是清洁的。显然，无论有没有大流行，我们呼吸的大量空气都会影响我们的健康和福祉。因此，虽然这项研究拨款集中在与新冠肺炎大流行和暖通空调系统大流行运行相关的研究上，但这项研究将对正常运行的建筑物产生长期影响。 用这笔RTI赠款购买的光学气溶胶光谱仪(OAS)和干式气溶胶发生器(DAG)培训的20名HQP将为暖通空调系统开发解决方案，以改善室内空气质量，并在大流行和正常运行期间减少传染病传播。在他们的职业生涯中，使用OAS和雾化器培训的HQP将很好地领导这些解决方案和其他解决方案在加拿大建筑中的实施，从而改善加拿大人的健康和福祉。

During the COVID-19 pandemic, most authorities have focused on reducing the contact and droplet transmission of SARS-CoV-2 (coronavirus) by recommending handwashing, surface sanitizing and 2-m physical distancing with little attention to the potential for airborne transmission of SARS-CoV-2. However, recent US Centers for Disease Control (CDC) and ASHRAE statements show the urgency of this RTI grant and our COVID-research to quantify and reduce airborne pathogen transfer in HVAC systems. ASHRAE: “Transmission of SARS-CoV-2 through the air is sufficiently likely that airborne exposure to the virus should be controlled. Changes to building operations, including the operation of heating, ventilating, and air-conditioning [HVAC] systems, can reduce airborne exposures.” CDC: “There are several well-documented examples in which SARS-CoV-2 appears to have been transmitted over long distances or times.” The proposed optical aerosol spectrometer (OAS) and dry aerosol generator (DAG) will allow us to generate aerosols and measure the key parameters affecting airborne transmission (i.e., the size, concentration and movement of aerosol particles). While the exact viral dose that is required to infect a person with COIVD-19 is unknown, humans infected with influenza generate around 2,000 infectious aerosol droplets per hour and even more during coughing, sneezing and singing. The distance that these aerosols can travel depends on their size and the ambient air velocity. While the coronavirus alone (0.1 µm) may remain airborne for days, exhaled aerosols containing body fluids and the coronavirus are expected to be 1 to 5 µm and may remain airborne for hours (e.g., 3 µm particle will settle at a rate of 1 m/h and natural indoor air currents could transport the aerosol nearly 100 m). The COVID-19 pandemic has increased public awareness of the importance of indoor air quality (IAQ) in buildings. Canadians spend over 90% of their time indoors and intake 15,000 L (17 kg) of air a day, which is much higher than our daily intake of food (~2 kg) and water (~2 L). Bottled water has mandated labels to indicate contents and purity, while the air we breathe is assumed to be clean. Clearly, the large volumes of air we breathe can impact our health and well-being with or without a pandemic. Therefore, while this RTI grant focuses on research related to the COVID-19 pandemic and pandemic operation of HVAC systems, the research will have long-term impacts for buildings under normal operation. The 20 HQP trained with the optical aerosol spectrometer (OAS) and dry aerosol generator (DAG) purchased with this RTI grant will develop solutions for HVAC systems that improve IAQ and reduce infectious disease transmission during pandemic and normal operation. During their careers, the HQP trained using the OAS and nebulizers will be well positioned to lead the implementation of these and other solutions in Canadian buildings and thus improve the health and well-being of Canadians.