If you get bitten by a hognose, it will be purely through your own negligence. They do not bite as a defense, only through a feeding response. Your hands would have to smell like food, or handle them soon after feeding. I have experience with people getting bitten with their hands smelling like a biscuit, and a leather glove.
The tricolors are hognoses only by common name, they are distantly related to the North American hognoses, so it is not safe to make any inferences about their venom from experiences with Heterodon.
Special handling methods are not required, simply wash her hands before. And being technically venomous should not alter at all your decision to get one. Where I used to work, Western hognoses were used specifically for kindergarten classes to introduce children to snakes.
-----
Virginia Herping
http://groups.yahoo.com/group/VaHS
Virginia Herpetological Society
http://fwie.fw.vt.edu/VHS
If there is a just God, how humanity would writhe in its attempt to justify its treatment of animals. - Isaac Asimov