So vinegar didn't eat the metal on those contacts?

My buddy Dave swears by the five second rule, but it totally failed him once. He dropped a piece of pizza on his apartment kitchen floor, snatched it right up, and ate it. He spent the next two days in the bathroom. That floor looked clean, but he had a cat walking around there. The study you mentioned makes sense, it's about what's on the surface, not the clock.

Would you just ask for the manager and show them your video?

So did you ever figure out what the actual problem was?

But is it really worth all that extra work? Most people just walk on floors, they don't study the rings. New wood gets the job done for way less money. Seen plenty of modern pine floors hold up just fine for decades. Feels like chasing a standard that doesn't matter anymore.