Well, I was hesitant to point this out, for fear of causing a panic, but it has to be done. If the "electromechanical grunge" at floor level described in the site linked in my previous reply is harmful to copper wire and insulation(and I wouldn't doubt it for a femtosecond)how much more harmful it must be to the far more sensitive human skin. Fortunately the solution is both obvious and simple and here
is an early example of an audiophile taking the necessary precautions before entering his listening room. It's clear from the expression on his face the confidence he has that he won't be experiencing the harmful effects that would have occurred if he listened with his feet closer to the floor.