QUOTE (Penina @ Feb 19 2008, 11:30 AM)

With wedding rings, I believe the rule is that if you knead dough with it and you sleep in it and shower in it, you can keep it on for netilas yadaim but not for mikvah since it's a higher standard of purity necessary. I don't know the source for that, but I know it has been told to me by multiple rabbis.
Anything that is considered a 'chatzitza' when toiveling the entire body, is considered the same for netilas-yodayim - SA 161:1
And if [the ring] was tight, the washing was/is not effective in a case where he is sometimes careful to remove it, for instance [a ring] containing a precious stone, which he is careful with when washing, so that it doesn't become dirtied by the water. And regarding a woman, even a ring with no 'even tovah', [since] it is usual for her to remove it when kneading dough, it is
always considered a 'chatzitza', even though she isn't particular about removing [the ring] to avoid getting it wet. However regarding men (who don't usually knead), there is no need to remove a ring with no precious stone before washing, even if it isn't loose, since he's never particular about removing it. - SA Harav 161:7, (based on the Raavad,Rashal, Taz, MA, etc. The ktzos-hashulchan in 33:1 elaborates further.)