Does Stainless Steel Disable RFID?

Since August 2007 the U.S. government has issued all American passports with a RFID chip embedded inside the cover. Realizing the vulnerability this created for sensitive personal information, the government also mandated that a "metallic element" also be installed in the cover, in order to block radio frequencies from leaving the passport when it's closed. The U.S. state department does not say if this metal used is stainless steel. But the fact that a form of metal is used shows that the U.S. government believes that at least some metals prove effective in blocking radio waves.

Businesses, realizing the concern consumers have about credit cards containing RFID technology, have made wallets and portfolios with stainless steel. The stainless steel is purported to block the radio waves emitted by the RFID chip inside credit cards and passports. Such wallets and portfolios may sell for $50 or more, depending on the product and retailer, and are marketed as the go-to products for securing your private data emitted by RFID technology.

The push for such protective measures comes from the ease in which criminals could "skim" your personal information in public places. Identity thieves and hackers have been known to amble around in public places with an RFID receiver concealed somewhere, such as in a briefcase. The thief attempts to get close to persons, hoping that the concealed RFID receiver will pick up RFID data transmitted by chips embedded in consumers' credit cards or passports. If successful, thieves could then use the stolen information to duplicate credit cards or passports.

Consumer Reports magazine reported in June 2011 that while shields or wallets marketed as RFID-blocking devices can make it more difficult for someone with an electronic reader to read consumer credit cards or passports, they don’t entirely block transmission of card data. A reporter even made her own RFID-blocking wallet comprised partly of duct tape lined with aluminum foil, and it proved more effective than a stainless steel-lined wallet selling for around $60. So while stainless steel has proven at least partly effective at blocking RFID emissions, it can't be said that it disables RFID completely or consistently, or even better than any other material.