Personalized air curtains promise to reduce respiratory exposure in industrial environments. This work explored the performance of normal safe helmets equipped with air curtains to prevent workers from particulate matters via computational fluid dynamics (CFD) method. The impact of human body heat, breathing modes (nose and mouth inhalation), and air curtain characters (opening angle, tilt angle, and opening width) on protective efficiency were analyzed under different air supply velocities. Results showed that the interaction between the downward jet supplied by the air curtain helmet and the free convection flow generated by the thermal human body significantly affects respiratory exposure. There is a critical air supply velocity, i.e., when the jet velocity is greater than this value, the flow field in the breathing zone was dominated by the downward jet; otherwise, it is dominated by free convection flow. Both human body heat and breathing modes have significant effects on the protective effect of the air curtain. The opening angle of 180^o, the tilt angle of 0^o, the opening width of 3 cm, and the air supply velocity of 0.5 m/s are recommended due to a high protection effect of around 1. This study can provide effective and intuitive guidance in applying personalized air curtains for respiratory protection in highly contaminated industrial environments.

个性化的空气幕有望减少工业环境中的呼吸暴露。这项工作通过计算流体动力学 (CFD) 方法探索了配备气幕的普通安全头盔的性能，以防止工人接触颗粒物。分析了不同送风速度下人体热量、呼吸方式（口鼻吸入）、气幕特性（开启角度、倾斜角度、开启宽度）对防护效率的影响。结果表明，气幕头盔提供的向下射流与热人体产生的自由对流之间的相互作用显着影响呼吸暴露。有一个临界供气速度，即当射流速度大于该值时，呼吸区流场以向下射流为主；否则，它以自由对流为主。人体热量和呼吸方式都对气幕的防护效果有​​显着影响。建议开启角度180°，倾斜角度0°^，开口宽度3cm，送风速度0.5m/s，防护效果高，约为1。在高度污染的工业环境中应用个性化空气幕进行呼吸保护的指南。