Will Permanent Magnets Damage Electronic Devices?
That depends on the type of device. Permanent magnets might cause damage to some electronic devices like phone cards, smart watches, and credit cards, while cameras, smartphones, CDs, and DVDs are unaffected. Magnetic fields can disrupt the device’s programming and stored information. Therefore, please keep your electronic equipment away from strong magnets, and be careful when you are around a strong magnetic field. You can check the following table to see if your devices are safe or not.
Table 1 Permanent Magnets’ Effect on Electronic Devices
|Danger||Phone cards, smart watches, SD/storage Cards, credit cards, computer equipment, video and audio tapes, pacemaker, and heart defibrillator|
|Unaffected||Cameras, mobile phones, smartphones (No danger for storage medium)
Vehicle keys, USB sticks, memory cards, CDs, DVDs
Table 2 Recommended Safe Distances for Permanent Magnets
|Nd-Fe-B||Magnetic field damaging at:||S-45-30-N
(strength 69 kg)
(strength 11 kg)
|Credit card, ATM card||40mT (=400G)||46mm||19mm|
|Parking garage, admission ticket||3mT(= 30G)||134mm||55mm|
|Pacemaker||1mT(= 10 G)||201mm||82mm|
Precautions in Daily Life
Strong magnets can be dangerous to the human body if we do not use them with caution. There are several aspects you need to pay attention to in everyday life to avoid injuries and damage.
Pinching: Strong magnets attract each other and might cause severe injuries. So take care when using strong permanent magnets like the Nd-Fe-B magnets.
Children: Keep magnets out of kids’ reach. If a child swallows a strong magnet, the injury will be rather serious because the mutual attraction of the magnets in the body would cause intestinal perforation in the body.
Pacemakers: Persons with pacemakers or defibrillators must avoid magnets completely since these devices are sensitive to strong magnetic fields. They are not allowed to be in an environment above 0.5mT (5 gauss).
Precautions While Using
Operators need to take care of the handling of magnets to avoid potential dangers as well.
They should learn about the magnets they are going to deal with. For instance, take good command of magnetic properties such as the dimensions, shapes, and environment. Check such information in advance.
They need to know about the criteria for using these magnets in case they are damaged or demagnetized. Avoid using magnets in hot and humid environments. Also, it might lose its magnetism if the magnet is heated near the Curie point. Thus, take care of these conditions during operation.
Take precautions according to the magnet types. The rare earth magnets need a coating on the surface to prevent oxidization. Ferrite magnets should be used under lower temperatures to avoid demagnetization. Take note of different magnets’ features for better performance.