Are you addicted to your BlackBerry? If you think you might be, ask yourself the following questions: When is the last time you postponed a face-to-face conversation with someone to check an "important" e-mail via wireless handheld? Have you ever composed an e-mail while driving? Do you secretly think the world would come to a screeching halt if you aren't available 24-hours a day?

If you answered yes to any of these questions, it's time for a refresher course in BlackBerry etiquette. Here are four rules for BlackBerry users:

There's no such thing as an "e-mail emergency." To break yourself of the habit of obsessively checking your inbox, remember: If someone really needed to get a hold of you, they'd pick up the phone. The world does not revolve around you. Chances are you're just not that busy and important. And insisting on checking your messages when in the company of friends, family and colleagues is destined to make you even less so.

Stick to a schedule. Decide on the times of day that you're going to check your e-mails and voicemail via BlackBerry and then tell the relevant people what they are. Some users prefer to do their BlackBerry correspondence in the morning and evening, while others keep theirs switched on only during work hours. Whatever you choose, the key is to draw limits.

Respect BlackBerry Blackout Zones. Even if you have the kind of job that demands you be chained to your BlackBerry, you should be aware that there are times when it's inappropriate — even dangerous — to use one. The most obvious examples are: While driving(!), during interviews and in class. But you may also want to adopt a "No Interruptions" policy when spending time with family and friends. Let's face it, no one likes the idea of playing second fiddle to a PDA.

Most of us allow ourselves to get away with murder when it comes to our BlackBerrys because we're convinced they're giving us a competitive edge, but this not always the case. Consider: A recent study by MIT's Sloan School of Management found that the feelings of control people get from checking their e-mail on a BlackBerry or similar hand-held device were counteracted by increased levels of stress.

It turns out that when you're always hooked in you're also always on edge.