Fig. 1.

ER_q (quanta h⁻¹) trends as a function of the viral load in sputum (cv, RNA copies mL⁻¹) and quanta-RNA copies correction factor (c_i) for different respiratory activities (voiced counting, whispered counting, unmodulated vocalization, breathing) and different activity levels (resting, standing, light exercise, moderate exercise, and heavy exercise). Zones representative of low (<1 quantum h⁻¹) and high (>100 quanta h⁻¹) quanta emission are indicated as blue and red shaded areas, respectively.