Short answer
Chip cards and phones are not affected by the small magnets in a name badge, but magnetic stripe cards and older magstripe hotel keys can be wiped if they are held directly against the magnet. Keep stripe cards out of the shirt pocket behind the badge.
| Item | Risk from direct contact |
|---|---|
| Chip or tap credit cards | Chip unaffected; the stripe on the back can be wiped |
| Magstripe hotel keys | Can be wiped |
| RFID key cards and badges | Generally unaffected |
| Smartphones | Generally unaffected; can interfere with the compass briefly |
| Pacemakers and ICDs | Keep magnets about 6 inches away |