Microorganism-ionizing respirator with reduced breathing resistance suitable for removing airborne bacteria

[Display omitted] •We demonstrated the ability of microorganisms ionizing respirator to remove airborne bacteria.•It uses miniaturized corona ionizer and separator electrodes.•Airborne bacteria was electrically charged and removed from air flow.•Its breathing resistance was less than that of commercial N95 respirator.•Contributes to the comfort and ease of breathing of the wearer. In this paper, we have demonstrated the feasibility of using microorganism-ionizing respirators with reduced breathing resistance to remove airborne bacteria. Using a miniaturized corona ionizer and two pairs of separator electrodes, airborne bacteria were ionized and removed from the airflow. Two microorganism-ionizing respirator designs were experimentally evaluated with flow rates ranging from ∼10 to 20 L/min and yielded airborne bacterial removal efficiencies of ∼75%–100%. Further, they were in close agreement with the analytical airborne particle removal efficiencies, at a similar range of flow rates. These flow rates also correspond to the breathing rates of standing and walking adults. More importantly, the breathing resistance could be reduced by more than 50% for flow rates of ∼200 L/min. Using manganese (IV) oxide coated mesh, the ozone concentration in the air outflow was reduced to less than 0.1 ppm, at a flow rate of ∼20 L/min, thus enabling safe use. The power consumption was less than 1 W.