Although a blind date is supposed to be your first meeting, don't let that stop you from protecting your own safety.
Always talk to your blind date in advance. Get a feel for what they are like. You may be able to tell just from talking to them on the phone if they are a crazy person, someone you are definitely not compatible with, or a gold digger.
Another useful tool is facebook. You can scope out their information without them knowing. By looking back at some of their wall posts you might be able to tell what kind of person they are.
If you think that the blind date is going to be a complete failure from your advanced knowledge then just think about canceling the date immediately because a bad blind date is something no one wants to experience.