Figure 4.

Quantification of SARS-CoV-2 following exposure to different energies of UV light. A, The concentration of viable SARS-CoV-2 following exposure to UV light measured by TCID₅₀ assay. Lower limit of detection was 0.5 TCID₅₀(log₁₀)/mL. B, The concentration of viable SARS-CoV-2 following exposure to UV measured by plaque assay. Both assays confirmed the complete inactivation of the sample after exposure to 0.04 J/cm2 or higher UV energy. Results are expressed as mean ± SEM (n = 3). Abbreviations: PFU, plaque-forming unit; SEM, standard error of the mean; TCID₅₀, 50% tissue culture infectious dose.