Dating in grad school
His bio indicates he met his wife while on a fellowship.
I generally agree with other posters that separate departments should be distant enough--except that you met at an academic conference, which suggests your areas of study overlap in some way.
As I write this, it’s a beautiful Friday—the sun’s out, it’s not freezing-my-butt-off cold, the weekend’s nigh, and I’m feelin fine! This is Mahnanymous, from [your grad program]—it was great to meet you at orientation!
In celebration of this OMG IT’S ALMOST SUMMER weather, enjoy this silly classic Muppets video I love, “Mahna Mahna.” Hey, is it cool if I call you Mahnanymous?! How are you liking [the program so far, particular class, place your school is in]?
You would have to recuse yourself from judging things she was part of, but what would happen if her advisor recommended she take a class in your field of expertise?
Obviously, as others have said, it would be unethical to violate the expectations set up in your school's policies (unless the policies themselves were unethical, such as Bob Jones University's old ban on interracial dating).
(Grad school is broad, after all...) If you study social psychology and she studies sociology of groups, say, you might have too much overlap to ethically date: she might have to curtail her academic interests to avoid taking your classes.
(That said, it would be problematic on the other hand if you two developed an academic relationship with an unrevealed desire for a romantic relationship still lurking.) Also consider what would happen if you dated but broke up acrimoniously.
Basically, NEVER date undergrads, and teachers shouldn't date any student "when a teacher has had -or might be expected ever to have-academic responsibility over the other party." ("Student" here includes grad student, postdoc, and clinical residents/fellows.) With what you know now, how much does your field fall within all the possible things she might think of studying?
“I want to make friends with/potentially date a woman in my grad program. If you’re a grad student, then you’re likely going to be spending a TON of time with at least some folks in your program.