An RF ID-tag is a small radio frequency (RF) transponder. It contains a tiny radio receiver, and a tiny radio transmitter that broadcasts an identifying code. One must use a special reader, which contains a relatively powerful radio transmitter. As RF ID-tag systems become more common, we must be aware of the hazard to electro explosive devices (EEDs). Examples are electrically fired squibs, igniters, detonators, and systems that contain them. When the special reader activates an RF ID-tag, at the same time the reader can induce an electric current, in any nearby wire. If the package contains detonators, then the reader might induce enough current in the leadwires of a detonator to fire it. In other words, in some cases, an RF ID-tag reader might cause an explosion. The RF power output of the reader is not, in general, a useful parameter in evaluating this hazard. Interactions between the reader and a detonator are in the induction region (near field) of the transmitting antenna. In evaluating this hazard, we must rely on laboratory tests of induced current. Results will differ for each type of reader. We also must know the safe or no-fire current level that characterizes the detonators. In any case, where we do not know enough to evaluate the potential hazard, we should not use RF ID tags on packages containing EEDs.
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