Table 1.
Probability distribution of the parameters used to calculate average viral indoor concentration: normal distributions were reported as average values ± standard deviation, whereas rectangular distributions were reported as median value and minimum-maximum range.
| Parameter | Distribution | Distribution parameters | references |
|---|---|---|---|
| Viral load, CTM (RNA copies mL-1) | Rectangular | 4.0 × 106 (2.4 × 106 – 5.5 × 106) | Measured, this study (see Section 3.1) |
| Inhalation rate while standing, IR (m3 h-1) | Rectangular | 0.52(0.47 – 0.57) | (Adams, W.C. , Measurement of Breathing Rate and Volume in Routinely Performed Daily Activities. Final Report. Human Performance Laboratory, Physical Education Department, University of California, Davis., Human Performance Laboratory, Physical Education Department, University of California, Davis. Prepared for the California Air Resources Board, Contract No. A033–205, April 1993., 1993., International Commission on Radiological Protection, 1994) |
| Particle volume while speaking, Vd-speaking (mL m-3) | Rectangular | 6.6 × 10-3(1.2 × 10-3 – 1.2 × 10-2) | Duguid (1945); Evans (2020); Johnson et al. (2011) |
| Particle volume while breathing, Vd-breathing (mL m-3) | Rectangular | 1.0 × 10-3(1.0 × 10-6 – 2.0 × 10-3) | (Buonanno et al. (2020); Morawska et al. (2009) |
| Room volume, Vroom (m3) | Normal | 70.0 ± 0.7 | Measured, this study (adopting an uncertainty of 2% according to Ambrosio Alfano et al., 2012) |
| Air exchange rate, AER (h-1) | Rectangular | 4.0(2.0 – 6.0) | Italian standard (Repubblica, 1997, Regione Lazio, 2011) |
| Particle deposition rate, k (h-1) | Log-normal | log10(−0.62) ± log10(0.30) | Chatoutsidou and Lazaridis (2019) |
| Inactivation rate, λ (h-1) | Rectangular | 0.32(0 – 0.63) | Fears et al. (2020);van Doremalen et al. (2020) |
| Time fraction of speaking, TFspeaking (-) | Rectangular | 0.8(0.6–1.0) | Estimated, this study |