Table 1. Ultraviolet-C (UV-C) dose response curve for Clostridioides difficile, the dose being shown in the first column and the response shown in the fifth column.

The average max cumulative dose is for the three radiometers in positions A, B, and C; SD = standard deviation; average positive control colony-forming units (CFU)/mL is the average of CFU for each position A, B, and C where each position involved two dilutions (N=6 for the mean), which also applies to the average UV-C treatment CFU/mL. The same control CFU indicates the same experiment. Log reduction uses base 10 (e.g., 2.25 = log₁₀ (1.47 X 10⁸/8.33 x 10⁵)). 

Average max cumulative dose (mJ/cm2)	SD	Average positive control CFU/mL	Average UV-C treatment CFU/mL	Log reduction
126.55	0.58	1.47 x 108	8.33 x 105	2.25
178.35	1.13	1.47 x 108	0	> 6
228.39	1.31	1.47 x 108	1.67 x 106	1.94
279.77	1.36	1.47 x 108	0	> 6
345.81	0.98	1.47 x 108	1.67 x 105	2.94
379.55	1.82	1.47 x 108	1.67 x 105	2.94
432.28	2.12	1.47 x 108	0	> 6
480.85	2.89	1.47 x 108	0	> 6
530.10	3.07	1.47 x 108	0	> 6
580.77	3.04	1.47 x 108	0	> 6