This article is from the Static Electromagnetic Fields and Cancer FAQ, by John Moulder firstname.lastname@example.org and the Medical College of Wisconsin with numerous contributions by others.
Effects on cardiac pacemakers have been reported for fields as low as
1.7 mT . The most common effect was triggering of the asynchronous
mode; the effect is very model and orientation dependent, and in the
models tested normal operation resumed when the pacemaker was removed
from the field . Some pacemakers also exhibited significant torque
was exposed . For this reason current static field guidelines
restrict exposures for wearers of cardiac pacemakers to 0.5 mT
[50,58,59]. It would be prudent to apply this restriction to other
implanted electronic devices, and to prosthetic devices as well,
although not all standards are explicit on this point.