National Air Transportation Center of Excellence for Research in the Intermodal Transport Environment (RITE), School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA.
Indoor Air. 2011 Aug;21(4):341-50. doi: 10.1111/j.1600-0668.2011.00709.x. Epub 2011 Mar 14.
Airliner cabins have high occupant density and long exposure time, so the risk of airborne infection transmission could be high if one or more passengers are infected with an airborne infectious disease. The droplets exhaled by an infected passenger may contain infectious agents. This study developed a method to predict the amount of expiratory droplets inhaled by the passengers in an airliner cabin for any flight duration. The spatial and temporal distribution of expiratory droplets for the first 3 min after the exhalation from the index passenger was obtained using the computational fluid dynamics simulations. The perfectly mixed model was used for beyond 3 min after the exhalation. For multiple exhalations, the droplet concentration in a zone can be obtained by adding the droplet concentrations for all the exhalations until the current time with a time shift via the superposition method. These methods were used to determine the amount of droplets inhaled by the susceptible passengers over a 4-h flight under three common scenarios. The method, if coupled with information on the viability and the amount of infectious agent in the droplet, can aid in evaluating the infection risk.
The distribution of the infectious agents contained in the expiratory droplets of an infected occupant in an indoor environment is transient and non-uniform. The risk of infection can thus vary with time and space. The investigations developed methods to predict the spatial and temporal distribution of expiratory droplets, and the inhalation of these droplets in an aircraft cabin. The methods can be used in other indoor environments to assess the relative risk of infection in different zones, and suitable measures to control the spread of infection can be adopted. Appropriate treatment can be implemented for the zone identified as high-risk zones.
客机客舱内乘客密度高，暴露时间长，如果有一名或多名乘客感染了空气传播传染病，那么空气传播感染的风险可能很高。受感染乘客呼出的飞沫可能含有感染源。本研究开发了一种方法，可预测在任何飞行时间内，客机客舱内乘客吸入的呼气飞沫量。通过计算流体动力学模拟，获得了指数乘客呼气后前 3 分钟内呼出飞沫的时空分布。在呼气后 3 分钟后使用完全混合模型。对于多次呼气，通过叠加法，可以通过将所有呼气的飞沫浓度添加到当前时间，然后通过时间推移获得一个区域内的飞沫浓度。这些方法用于确定在三种常见情况下，4 小时飞行中易感乘客吸入的飞沫量。如果该方法与飞沫中存活的传染性病原体的数量和信息相结合，则有助于评估感染风险。
感染者在室内环境中呼出的飞沫中所含传染性病原体的分布是短暂且不均匀的。因此，感染的风险会随时间和空间而变化。本研究开发了预测呼气飞沫在飞机客舱中的时空分布以及吸入这些飞沫的方法。这些方法可用于其他室内环境，以评估不同区域的相对感染风险，并采取适当措施控制感染的传播。可以对被确定为高风险区域的区域进行适当的治疗。
