考虑人员密度分布的儿童医院候诊空间感染风险研究

Risk of Infection in the Waiting Rooms in Children’s Hospitals Considering Population Density Distribution

医院候诊室由于人员等候时间长、聚集严重,是流感暴发的高危地带,既有研究表明可以通过适当的通风控制策略有效降低候诊室的感染风险.本文对使用频率最高的小型候诊室感染风险及粒子清除效率进行研究.通过图纸调研和实地调研,提炼综合儿童医院内科候诊室典型室内空间,以内/外走廊送风启闭、候诊室内风口形式、通风换气次数以及外走廊风速为研究变量,探究其对候诊室内粒子运动轨迹、粒子清除效率以及感染风险分布的影响.通过CFD非耦合粒子扩散仿真和Anylogic人员仿真,并结合Wells-Riley经典感染方程,得到医院候诊空间人员感染风险.研究表明:不同候诊室风口形式对患者附近粒子扩散轨迹有较大影响,直接影响粒子清除效率和清除途径;对于小型候诊室优先选择格栅送风,避免选用散流器;鼓励开启外走廊送风,同时关闭内走廊送风,可加速候诊室内的气体流动,同时避免粒子扩散进入内走廊.相同条件下,开启内走廊送风会明显增加外走廊粒子浓度,易造成更大范围的院内感染.不同送风形式下存在最优室内换气率,一般建议在10/h左右,过高的换气率并不会提高粒子清除效率,反而会增加候诊室的高风险面积比.该研究成果可为降低医院感染风险的通风设计提供理论支撑.

Due to the long waiting time and serious gathering of people,hospital waiting rooms are a high-risk zone for influenza outbreaks.Existing studies have shown that appropriate ventilation control strategies can effectively re-duce the risk of infection in waiting rooms.This article studies the infection risk and particle removal efficiency of the most frequently used small waiting rooms.Through drawing and field investigations,the typical indoor space of the internal waiting room of a general children’s hospital was refined.The air opening and closing of the internal/external corridor,form of the air outlet in the waiting room,number of ventilation,and wind speed in the external corridor are used as the research variables.Further,their effects on particles in the waiting room and the influence of movement trajectories,particle removal efficiency,and infection risk distribution are explored.Through computational fluid dynamics uncoupled particle diffusion simulation and Anylogic personnel simulation,combined with the Wells-Riley classic infection equation,the infection risk of personnel in the waiting space of the hospital is obtained.Our research obtained the following results:Waiting room air outlets have a great impact on the particle diffusion trajec-tory near patients,which directly affects the particle removal efficiency and removal path.For small waiting rooms,grid air supply is preferred,and the use of diffusers is avoided.Hence,it is recommended to turn on the air supply in the outer corridor and close the air supply in the inner corridor.This method can accelerate the gas flow in the waiting room while avoiding the diffusion of particles into the inner corridor.Under the same conditions,turning on the air supply in the inner corridor will significantly increase the particle concentration in the outer corridor,which is likely to cause a wide range of nosocomial infections.There is an optimal indoor air exchange rate under different air supply modes,and a value of approximately 10/h is generally recommended.Excessive air exchange rate will not increase the particle removal efficiency but will increase the high-risk area ratio of the waiting room.The research results can provide theoretical support for ventilation design to reduce the risk of nosocomial infections.