C. Study design

The separate continuum phase and Lagrangian simulations are conducted for each of the three models: (a) model at full passenger capacity (60 passengers), (b) model with reduced passenger capacity (40 passengers), and (c) model at full passenger capacity with sneeze guards/shields between passengers. One passenger located on the seventh row [7C seat in Fig. 1(c)] of the cabin zone exhales aerosol particles, which may be inhaled by other passengers. The index patient is the only source of aerosol particles in the simulations. The standard filtration efficiency of particulate filters used in the aerospace industry exceeds 99.99%.49 Aerosol particles that exit through the outlet are assumed to be perfectly filtered and are not recycled into the system. Susceptible passengers are assumed to inhale air at a rate of 20 l/min and can, therefore, inhale aerosol particles in the air. The inhalable aerosol fraction and the fraction of aerosol deposited on various surfaces (including passengers) are quantified for relative risk assessment. Inhalation and exhalation cycles are not considered as steady state continuum phase simulations are employed. The inhalable fraction is uncorrected for the inhalation-to-exhalation time ratio and internal deposition fraction. The inhalable fractions reported herein are, therefore, useful for relative comparison of the intervention measures and do not represent absolute values for inhalation dosimetry. A wide range of particle sizes (1–50 μm) is investigated for each of the three models considered to understand the effect of particle size on the efficacy of the measures in reducing aerosol transfer and passenger contamination.