The corridor effect in droplet and aerosol pathogens transmission

This study investigates the effect of natural ventilation on the distribution of airborne pathogens in narrow, low-ceiling corridors typical of hotels, offices, or cruise ships. Two scenarios are examined: a milder cough at 6 m/s and a stronger cough at 12 m/s. A reference baseline case with no airflow is compared to cases featuring an incoming airflow velocity of 1 m/s (3.6 km/h), examining differences in the dispersal of respiratory droplets from two individuals coughing spaced 5 meters apart. Both individuals cough in the direction of the airflow, assuming one-way traffic to minimize airborne pathogen transmission. Findings indicate that airflow accelerates past the door, exceeding 3 m/s, with gusts reaching 4 m/s due to interaction with recirculation zones. This acceleration affects droplet dispersal. Larger droplets (>150 μm) maintain a ballistic trajectory, traveling 2–4 m, potentially increasing transmission risk but suggesting that a 5-m distancing policy could suffice for protection. Smaller droplets (<150 μm), especially those <100μm, spread extensively regardless of cough strength while containing the most viral mass overall. Thus, distancing alone is insufficient. The study recommends that additional safety measures be enforced, such as wearing masks, stricter usage protocols for corridors by limiting corridor use to one person every 20–30 s, or eliminating natural ventilation when feasible to effectively mitigate transmission risks in such environments.