I was interested to read a randomised controlled trial of pulsed xenon UV (PX-UV) for room disinfection in Clinical Infectious Diseases. In this study, PX-UV was not associated with a reduction in HCAI. Some may be quick to say that this provides evidence that “automated room disinfection systems don’t work”, but there are important differences in the technologies involved as well as the usual strengths and limitations of the study methodology that could explain this outcome.