Tomás, Ana LuísaReichel, AnnaSilva, Patrícia M.Silva, Pedro G.Pinto, JoãoCalado, InêsCampos, JoanaSilva, IlídioMachado, VascoLaranjeira, RobertoAbreu, PauloMendes, PauloSedrine, Nabiha BenSantos, Nuno C.2022-09-092022-09-092022J Photochem Photobiol B. 2022 Sep;234:1125311011-1344http://hdl.handle.net/10451/54423© 2022 Elsevier B.V. All rights reserved.The SARS-CoV-2 pandemic emphasized effective cleaning and disinfection of common spaces as an essential tool to mitigate viral transmission. To address this problem, decontamination technologies based on UV-C light are being used. Our aim was to generate coherent and translational datasets of effective UV-C-based SARS-CoV-2 inactivation protocols for the application on surfaces with different compositions. Virus infectivity after UV-C exposure of several porous (bed linen, various types of upholstery, synthetic leather, clothing) and non-porous (types of plastic, stainless steel, glass, ceramics, wood, vinyl) materials was assessed through plaque assay using a SARS-CoV-2 clinical isolate. Studies were conducted under controlled environmental conditions with a 254-nm UV-C lamp and irradiance values quantified using a 254 nm-calibrated sensor. From each material type (porous/non-porous), a product was selected as a reference to assess the decrease of infectious virus particles as a function of UV-C dose, before testing the remaining surfaces with selected critical doses. Our data show that UV-C irradiation is effectively inactivating SARS-CoV-2 on both material types. However, an efficient reduction in the number of infectious viral particles was achieved much faster and at lower doses on non-porous surfaces. The treatment effectiveness on porous surfaces was demonstrated to be highly variable and composition-dependent. Our findings will support the optimization of UV-C-based technologies, enabling the adoption of effective customizable protocols that will help to ensure higher antiviral efficiencies.engCOVID-19Non-porous surfacesPorous surfacesSARS-CoV-2UV-C irradiationViral inactivationjournal article10.1016/j.jphotobiol.2022.1125311873-2682