Just Ask: Would wrapping credit cards in foil prevent theft of information? (2024)

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Question:

I’ve been hearing a lot about

radio frequency identification security

and credit cards.

What I want to know is, if I wrap my credit cards in a couple of layers of heavy-duty aluminum foil when I travel, will it foil (pun intended) would-be criminals who go around airports and tourist destinations scanning people’s wallets and purses for credit card numbers for nefarious purposes?

Will this thwart these individuals, or do I really need to buy an expensive steel-reinforced wallet?

– Anonymous,
South Hadley

Answer

: This is only a problem if you have a newer-type credit card that can be read by proximity – like by just putting it up against a reader on a vending machine or gas pump, and it doesn’t need to be swiped, said

Prashant Shenoy

, professor of computer science at the

University of Massachusetts at Amherst

.

The fear is that a crook could put a scanner in a briefcase and walk through a crowd gleaning all the credit card information without ever taking the cards from the victim’s pockets, he said.

“While wrapping one’s wallet in tin foil might offer protection, this would be true only if one has credit cards that are vulnerable to scanning,” Shenoy wrote in an email.

Normal credit cards have a magnetic swipe feature – those cards can not be scanned in this way. Some new credit cards have a feature called “chip and pin” – these cards are quite common in Europe and still relatively rare in the United States. Those cards can be read by a scanner, but if one has a “chip and pin” card, then merely reading the card is not of much use; you also need a PIN to use it (like the old ATM cards that need a card number and PIN number to withdraw cash).

“So I’d say if one has the normal credit cards with magnetic swipe like most of us do, there is not much to be gained from wrapping the card in tin foil. If one has the newest chip and pin card (or the so-called chip and sign card) then the tin foil might help,” Shenoy wrote.

“That said, I think the risk of getting your wallet or smartphone stolen by pickpockets in foreign countries is still much greater than getting your wallet scanned. So common sense precautions might serve you better than more elaborate measures such as using tin foil.”