Neodymium Magnet Dangers
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Health Hazards
Neodymium magnets should always be handled carefully. Some that are slightly larger than the size of a penny are powerful enough to lift over 10 kilograms. Strong magnetic fields can disrupt the operation of some internal medical devices such as pacemakers. While most solid state electronic devices are not affected by magnetic fields, some medical devices are not manufactured to mitigate the effects of strong magnetic fields. These design flaws can be hazardous to patients using these devices. If swallowed, neodymium magnets can cause lethal conditions by joining up inside the intestine.
An NIB's magnetic force increases with the size of the piece of ferromagnetic metal and larger neodymium magnets can severely pinch skin or fingers, or even break bones when suddenly attracted to a magnetic object. Operating a large neodymium magnet close to smaller magnetic objects (keys, pens, etc.) and larger magnetic surfaces (radiator or a car, for example) can be dangerous if the person is caught between the magnet and the magnetic object or surface.
Neodymium magnets are made with special powders and coatings, so they are very fragile. They are often plated with a metal such as nickel. The magnets can fracture at temperatures over 150 °C, or under impact as a result of their own acceleration. When this happens, in some cases the magnets may break apart so suddenly that flying pieces can cause injury.
Other dangers
Caution must be taken when using neodymium magnets. A neodymium magnet is powerful enough to destroy the contents of a floppy disk to such an extent that the information is unrecoverable, a guarantee not present with techniques such as formatting the disk. In regards to the information contained on the magnetic stripes of credit cards, neodymium magnets are amongst the only materials that can successfully erase this data. Neodymium magnets are often strong enough to not only magnetize color CRT shadow masks, but also physically deform the mask itself. Such damage is typically not repairable by degaussing.
