This option allows Bob to disinfect masks and any kind of objects that fit in its 27x27x34 cm basket.

UV-C technology has been used for years for sterilising drink water or devices in hospitals (so called UVGI – UV Germicidal Irradiation), and recently used by some American hospitals to help fighting the masks shortage[1]. The underlying principle is the emission of high energy photons that break the DNA and RNA of bacteria and viruses.

According to several studies carried on SARS-COV-1, which is very similar to current SARS-COV-2 and is thus a good proxy to deal with it, an irradiation dose of 2 to 5mJ/cm² is enough to kill SARS-COV-1. For prudence sake, we apply a 20 times higher irradiation dose of 100mJ/cm². The reduction of viruses follows a decreasing exponential law, and is thus of log 3 reduction, meaning killing 99.9% of viruses. To ensure user safety, Bob shuts instantly UV-C lighting if the door opens and the door porthole has an extra additive to filter harmful wavelength while letting visible light go through.

The disinfecting device can be used on a dry mode (without water) to clean objects such as masks, phones, or wallets. It works also with glass mode and express mode (20 minutes) to clean cups, cutlery, or Tupperwares at the office.