|MadSci Network: Computer Science|
These systems do not cause any sufficient Electro-Magnetic Force (EMF) that
can cause damage to a computer.
However the only way to make sure is to test it out. If you find that your monitor acts funny (the old CRT types, or have a TV placed on it, and you find unusual lines), then this magnetic field is sufficient to erase bits of your Hard Disk Drives or cause a sudden crash of your computer due to RAM erasures.
The above step is given only so that you will be sure. But typically, this contains a flexible heat coil that goes through the mat. It just heats up to a small degree, and so a very small current passes through it.
In any case, if you find that it interferes, just have a EMF shield bought for the CPU. The case can also be upgraded to one that has a complete metal cover. They are typically metal enclosures that do not have a direct visible contact to your CPU.
Hope this answers your questions. A reminder though: this forum does not let you ask questions relating business, and do not guaranty any accuracy of the answers provided. So if you really want something done, please contact an approved consultant (public engineer, in this case.)
Try the links in the MadSci Library for more information on Computer Science.