You'll probably get a lot of different opinions on that one, Roy. I change the water and wash their water bowls every 10 days to 2 weeks, but I haven't heard of any "rule." This always involves a little bit of handling, but I try to make it as quick as possible. I just don't want bacteria to build up in their water dishes. As far as the Carefresh, I steer clear of particularly dusty bedding material that could enter their lung(s). I probably error on the side of being over cautious, but I tried using bark bedding and am even considering going back to paper towels. I wouldn't even consider bark near birth. The bark looks much better and makes it easier to clean up feces/urates, but it makes the snakes dusty and dulls their coloration... not to mention the potential effect on their lung(s). These are just my personal preferences, though.
Rick