Does a very light technology exist without active signal interference that could alert a deaf implanted child if his hearing aid fell from his ear and was about to be lost, such as by vibrating a wristwatch?
There is no such technology to my knowledge that would accomplish what you are asking. Any RFID device small enough to connect to a hearing aid would likely not have the energy to communicate with a smart watch, unless it were built into the hearing aid. There are tiny RFID tags on the market, but they have a very short read range (a couple of inches) and would not be of much use to prevent the loss of an expensive hearing aid. Sorry I can’t be of more help.
—Mark Roberti, Founder and Editor, RFID Journal
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