How do contactless cards work?

skybluesaver

Hi all, sorry if this question has been asked before.
I have a couple of contactless cards now. Like the speed and ease of use but do have some concerns around safety.
Do these cards constantly emit a signal and can they be a potential risk to human health if they are emitting a radio signal like a mobile phone for example?
Many Thanks.

Chino

skybluesaver wrote: »

Do these cards constantly emit a signal and can they be a potential risk to human health if they are emitting a radio signal like a mobile phone for example?

These cards only become active when placed within a couple of inches of a contactless terminal. The contactless terminal provides the card with power.

http://www.theukcardsassociation.org.uk/contactless_consumer/what_is_contactless.asp

eddddy

Contactless cards contain 'passive RFID chips'. 'Passive' means they have no internal power source.

The contactless reader emits an electromagnetic field. The RFID chip uses the electromagnetic field to create power - to emit a signal.

So the cards only power up and emit signals when they are in an electromagnetic field (e.g. near a contactless card reader)

So it's the card readers that will kill you, not the cards.


It's the same technology as security tags and the alarms by the shop doors.

That's why I always wear tin-foil underwear when I go to Tesco.

bigadaj

Lead pants would be better.

skybluesaver

eddddy wrote: »

Contactless cards contain 'passive RFID chips'. 'Passive' means they have no internal power source.

The contactless reader emits an electromagnetic field. The RFID chip uses the electromagnetic field to create power - to emit a signal.

So the cards only power up and emit signals when they are in an electromagnetic field (e.g. near a contactless card reader)

So it's the card readers that will kill you, not the cards.


It's the same technology as security tags and the alarms by the shop doors.

That's why I always wear tin-foil underwear when I go to Tesco.

Whatever floats your boat lol
Cheers folks.

Katgrit

Contactless cards can interfere with pacemakers. I don't know if it's ALL pacemakers or just some types. My Dads had a variety of cancers so he needed an MRI compatible pacemaker (if that's what makes the difference?) and was advised by the consultant he shouldn't use contactless cards. Trying to get a replacement non-contacless card from NatWest was a battle and half!!

(also advised not to use mobile phone on left ear as side of body closest to pacemaker, and not to keep mobile phone in shirt breast pocket as he had previously done)

agrinnall

Katgrit wrote: »

Contactless cards can interfere with pacemakers. I don't know if it's ALL pacemakers or just some types. My Dads had a variety of cancers so he needed an MRI compatible pacemaker (if that's what makes the difference?) and was advised by the consultant he shouldn't use contactless cards. Trying to get a replacement non-contacless card from NatWest was a battle and half!!

(also advised not to use mobile phone on left ear as side of body closest to pacemaker, and not to keep mobile phone in shirt breast pocket as he had previously done)

This article has some information on a study that some people believe could indicate the potential for RFID interference with medical equipment. I doubt very much if the low power of a contactless card (which wouldn't transmit unless in proximity to a reader anyway) would be much of a risk compared to a huge range of other transmitting equipment.

http://www.smartcard.co.uk/articles/RFIDStudy.php