Examination of Peak Power Dependence in the UV Inactivation of Bacterial Spores

We examine whether the rate of delivery of photons from a UV radiation source has an effect on the inactivation of spores. We directly compare the output of a high-peak-power UV laser source at 248 nm to a low-power continuous lamp source (254 nm) in the inactivation of Bacillus subtilis spores. The two UV sources differ by a factor of 10(8) in peak power. Contrary to previous reports, no clear differences in spore survival were observed.