There should be no problem if someone wearing a necklace with a
magnetic clasp were to hug someone with an implanted placemaker or
defibrillator so long as the clasp of the necklace is not in the
front of the wearer where it would directly contact the device.
This topic keeps coming up from time to time. This time I decided to
go directly to the source for an answer. I called patient services
at Medtronic, one of the largest manufacturers of pacemakers and
implanted defibrillation devices. According to the woman with whom I
spoke, the safe distance for almost any magnet is six inches away
from the device. She said the small magnet in a necklace is okay so
long as a long chain does not slip around to the front and lay next
to the device. And she also recommended not sleeping with a necklace
having a magnetic clasp. Same with a bracelet with a magnetic clasp.
Just keep it 6 inches away from the device. The official info from
Medtronic is found at