Following both the earlier posts, your title mentions collector, and the text mentions vac. Not sure which you mean, but in either case my answer would be what Jason said: I don't. There are no safety issues, though personal comfort does come into play. I simply try to avoid (on the DC and ductwork) coming into contact with anything while the system is running. With my vac I haven't experienced anything but minor annoyances, and I've learned to live with it.