Bacillus subtilis spores
Kowalski 2009 · 254 nm
Test conditions & context
Type Bacterial spore
Medium Air
Test wavelength 254 nm
Author Kowalski
Year 2009
UV-C dose–response (D-values)
A D-value is the UV-C dose (in mJ/cm²) needed for a given log-reduction. D90 = 90 % inactivation = 1-log; D99 = 99 % = 2-log; D99.9 = 99.9 % = 3-log, and so on. Values come from the cited study under its specific test conditions.
Reduction log Dose (mJ/cm²)
D90 90 % 1-log 22 mJ/cm²
D99 99 % 2-log 44 mJ/cm²
D99.9 99.9 % 3-log 66 mJ/cm²
D99.99 99.99 % 4-log 88 mJ/cm²
Morphology & UV-C resistance
Morphology class Bacterial endospore
Bakterium in Endospore-Form: Mehrschicht-Coat + DPA-Calcium-Komplex + dehydratisiertes Genom. ~100× resistenter als aktive Zelle.
Primary source
Kowalski (2009). doi.org/10.1016/j.buildenv.2007.10.009