Tiny Brown Bugs in the Basement?

I have tiny brown bugs. They are just about the size of a dot. They are on my stainless steel worktable in the basement. I have sprayed numerous times. As soon as I clean it up they start appearing again. I found them upstairs once, but I think I brought them up on my clothing. I live in Denver, Colorado (very dry). No food in the basement. Kitty litter boxes are on the other side of the basement. Thanks in advance for advice.

By Michele from CO