The industrial, scientific and medical (ism) radio bands are radio bands (portions of the radio spectrum) reserved internationally for the use of radio frequency (rf) energy for industrial, scientific and medical purposes other than telecommunications. examples of applications in these bands include radio-frequency process heating, microwave ovens, and medical diathermy machines. the powerful emissions of these devices can create electromagnetic interference and disrupt radio communication using the same frequency, so these devices were limited to certain bands of frequencies. in general, communications equipment operating in these bands must tolerate any interference generated by ism equipment, and users have no regulatory protection from ism device operation. despite the intent of the original allocations, and because there are multiple allocations, in recent years the fastest-growing uses of these bands have been for short-range, low power communications systems. cordless phones, bluetooth devices, near field communication (nfc) devices, and wireless computer networks all use frequencies allocated to low power communications as well as ism, although these low power emitters are not considered ism.