No one can read or access the information on the security chip in a U.S. electronic passport without you knowing it, even if someone is standing next to you with a special reader, for example. The United States has gone to great lengths to protect the privacy and security of its citizens when they carry and use an epassport. For one thing, there is a shield in the passport cover, so the chip in the cover cannot be read when it is closed. Also the epassport chip is "locked" with a key that is unique to each epassport. The border agent must first physically open your passport book to get the printed key to access the chip information. The smart card chip encrypts, or scrambles, the data before transmitting it to the passport terminal, making the information useless to any eavesdropper. It's also important to know that the epassport chip only communicates over very short distances of one or two inches.
Want to learn more about how the epassport protects your privacy and safety? Read JustAskGemalto.com's Tutorial on the U.S. Electronic Passport.