I have seen these clear red vinyl curtains on several of the car and motorcycle building shows on t.v. They seem to be used to separate work stations or to create a separation between different projects (i.e different cars or bikes). You can see through them but they look like a red shower curtain. What are these, why are they used, and why are they always red? I have always wondered about them but my curiosity peaked last week when I ended up at a decommissioned GM assembly plant (my visit was work related). Anyway, there were several of these red vinyl curtains throughout the various assembly rooms that I entered. Curiosity finally got the best of me. Any ideas?