An article 100 and realted methods for reducing a microbial population on an article 168, wherein apparatus 100 includes a chamber in an article-holding basket 164 retains article 168 in an up-right position within the cahbmer an enclosing article 168. A heating system 172 introduces dry heat, moist heat, and, if desired, a combination of moist heat and dry heat into the chamber. A fluid supply system delivers a predetermine amount of fluid to a heating reservoir 174, which is disposed above heating system 172 to provide the moist heat.