An area shielded. say a bldg. with an open roof, say with a dose rate of 200 MR/HR.contact on the object maybe 80 MR/HR GA.how would sky shine come into play on clear days? or any day? this is for boundry set points. Barriers. ect. ===== mark sasser at duke99301@yahoo.com you can also reach me at duke9930@concentric.net __________________________________________________ Do You Yahoo!?