Planning UV-C Dose: Fluence, Pathogen Targets and the Exposure-Time Calculator

Calculate the time required for UV disinfection automatically. Efficient and easy to use.

Germicidal effect is governed by fluence — lamp intensity multiplied by exposure time. Wolf-e Robotics' free calculator converts device power and room size into the exposure times needed to inactivate MRSA, SARS-CoV-2 and Clostridium difficile.

Effective UV-C disinfection is a question of dose, not guesswork. Germicidal activity sits in the UV-C band of 100–280 nm, peaks around 265 nm, and Wolf-e Robotics devices operate at 253.7 nm. Absorbed UV-C alters the DNA and RNA of micro-organisms so they can no longer reproduce; a cell that cannot multiply to an infectious number is effectively dead. Viruses, bacteria and fungi are all radiosensitive, though fungi and spores require a higher dose than bacteria.

What determines success is fluence — the total radiation dose a surface receives, a product of lamp intensity and exposure time. Boston University research established that 5 mJ/cm² inactivates 99% of SARS-CoV-2, while 22 mJ/cm² achieves 99.9999% inactivation. Translating those targets into real device settings is where planning tools matter.

Wolf-e Robotics, based in Ploiești, offers a free UV-C exposure-time calculator. The user selects device type (unidirectional or omnidirectional), tube power (8, 15, 30, 55, 200 or 325 W per tube) and number of tubes; the tool returns total electrical power in watts and total UV-C irradiance in μW/cm² measured at one metre. Entering room dimensions then produces the exposure times required to inactivate common pathogens — including MRSA, SARS-CoV-2 and Clostridium difficile — alongside a graphical efficiency comparison across the Wolf-e Robotics portfolio. Because the process is chemical-free it leaves no residue or hazardous waste, and professional units add presence sensors and use ozone-free sources.

Try the exposure-time calculator and confirm dose planning for your rooms with Wolf-e Robotics via MedicalExpo.

***

/UV-C fluence, disinfection dose calculator, MRSA inactivation dose, SARS-CoV-2 UV dose, germicidal exposure time/