Dacunto P, Moser D, Ng A, Benson M
Department of Geography and Environmental Engineering, United States Military Academy, 745 Brewerton Road, West Point, NY 10996 USA.
Department of Civil and Mechanical Engineering, United States Military Academy, West Point, NY 10996 USA.
Int J Environ Sci Technol (Tehran). 2022;19(2):1057-1070. doi: 10.1007/s13762-021-03564-z. Epub 2021 Jul 30.
A study of aerosol dispersion was conducted in a university classroom using a CO tracer gas emitted from three source locations in a steady release, one source location per test. The tracer gas emitted from the single source location represented the potentially infectious aerosol droplets emitted from a single student and was thus a way to examine the influence of one sick student on the rest of the class. Two parameters were adjusted during the testing-the spacing of the desks, which included a spread and compressed configuration, and the inclusion of three-sided clear dividers attached to the student desk surfaces. Tracer dispersion was measured through the use of monitors in 13 locations within the classroom, with eight monitors representing seated student locations, four monitors representing a standing instructor along the classroom front, and one monitor at the return vent in the ceiling. As expected, spacing strongly influenced concentration levels at desks adjacent to the source location. The use of dividers reduced overall student and instructor location tracer concentrations when compared to desks without dividers in most cases. Finally, the influence of air change differences on the results was noted with consistent trends. The experimental construct provides a systematic means for classroom testing that may be broadly applicable to various configurations of classrooms beyond the one tested.
在一所大学教室里进行了一项气溶胶扩散研究，使用从三个源位置稳定释放的一氧化碳示踪气体，每次测试一个源位置。从单个源位置释放的示踪气体代表单个学生释放的潜在传染性气溶胶飞沫，因此是一种研究一名患病学生对班上其他学生影响的方法。测试过程中调整了两个参数——课桌间距，包括展开和压缩配置，以及在学生课桌上安装三面透明隔板。通过在教室内13个位置使用监测器来测量示踪剂扩散情况，其中八个监测器代表就座学生的位置，四个监测器代表教室前排站立的教师位置，一个监测器位于天花板上的回风口处。正如预期的那样，间距对源位置附近课桌上的浓度水平有很大影响。在大多数情况下，与没有隔板的课桌相比，使用隔板降低了学生和教师所在位置的示踪剂总体浓度。最后，注意到换气差异对结果的影响呈现出一致的趋势。该实验结构为课堂测试提供了一种系统方法，可能广泛适用于除所测试教室之外的各种教室配置。
