Keep out of reach of children
Although magnets can be wonderful toys and highly educational, these are 'adult' toys, and not for children. Small children should not be allowed to handle any of our magnets at all! Older children should handle them only under adult supervision, and wearing proper safety equipment (depending on the size and power of the magnets being used). Small magnets pose very little hazard, but large magnets should be handled with extreme caution.
Pacemakers and Defibrillators
Pacemakers and defibrillators can be sensitive to strong magnetic fields. If you or someone in your household has a pacemaker or defibrillator, or has health issues which require that you wear electronics of any sort, avoid magnets completely until you consult your doctor!
Pinch and Eye Hazard
Strong magnets can pose a serious pinch hazard due to their attractive force on each other and to any metal object containing iron. Usually surprise is an issue--they can jump out of your hands and snap together from a surprising distance before you realize what is happening. Though small magnets are quite safe, larger sizes are strong enough that they can pinch you like a pair of pliers, and be very difficult to remove from your fingers without help.
Damage to magnetic storage media
Magnetic fields can cause damage to magnetic storage media. These include: cassette tapes, floppy disks, credit cards, video tapes, and computer hard drives. As mentioned in the FAQ, we have never damaged or deactivated a credit card or phone in years of testing. When not in use, we recommend storing them in the included plastic vial away from your wallet and phone just to be safe.
Damage to Electronics
Certain electronic devices are sensitive to magnetic fields and may be damaged permanently or temporarily disabled if exposed to a magnetic field that is too strong. Any video screen or television will become distorted and/or discolored if exposed to a strong magnetic field. While damaged screens can usually be demagnetized, it's often tricky and may require qualified service technicians to do so. Other electronic devices like cellphones and pagers can also be damaged. Store your magnets in a safe place away from electronics of any kind.
Although there are no known health risks involving the handling of permanent magnets of the sizes we sell, just to be on the safe side we would advise pregnant women to avoid any exposure to strong magnetic fields.