But they need to leave and arrive at the office at some point. Accordingly, you just need to find out from security when that is and intercept them between their vehicle and getting in the building.

At least it worked in Chicago Fire.

I forget the full measurements for UV-C. I want to say UV-C is between 280 nm and 200 nm. After investigating, it looks like Far C is 222 nm with filters set for safety purposes at 233 nm.

Columbia University is the originators of the Far UV C concept and studies. Here's some starting research points.

https://www.cuimc.columbia.edu/news/new-type-ultraviolet-light-makes-indoor-air-safe-outdoors

And they have their technology licensed to USHIO.

https://www.ushio.com/product/care222-filtered-far-uv-c-excimer-lamp-module/

UV is denoted in at least 4 different wavelengths: A, B, C, and Far C. UV lights for sterilization purposes are designed to put out UV C at a specific measurable distance at a large enough intensity to disrupt the DNA in bacteria and virus.

UV C at this intensity is not safe to be directly in contact with, though glass does limit how much UV C passes through. Depending on the size of the room, UV disinfection lights need to be ran multiple times in different positions because of shadows and distance. They're really only good for about 8 ft wide areas.

Far UV C is in trial phases and is a specific wavelength at the end of the UV C range that is both safe for skin exposure because it only affects the top layer of the epidermis, which is already dead, while at the same time being more destructive to the baddies to the point of being considered safe to treat surgical site infections or being built into normal light fixtures.