Just read this warning from a Miele induction hob technical detail
Danger!
An electro-magnetic field is developed in the immediate surrounding area of an induction hob when it is switched on. Under certain circumstances this could affect the correct operation of a heart artificial pacemaker. In case of any doubt, contact the pacemaker manufacturer or your doctor.
Danger!
When checking induction hobs for correct operation do not leave superfluous metal objects on the ring. The magnetic field developed could cause such objects to heat excessively and lead to a risk of burning.
Warning!
Calculators, computer disks, credit cards or other magnetic data storage media should not be brought into the immediate proximity of the induction hob when it is switched on as there is a risk of data loss.
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