GUIDE TO INSPECTIONS OF ELECTROMAGNETIC
COMPATIBILITY ASPECTS OF MEDICAL DEVICE
APPENDIX A - DEFINITIONS
ELECTROMAGNETIC COMPATIBILITY (EMC) - the ability of a device to function a) properly in its intended energy environment and b) without introducing excessive electromagnetic energy that may interfere with other devices.
ELECTROMAGNETIC DISTURBANCE (EMD) - any electromagnetic phenomenon which may degrade the performance of equipment (e.g., devices). Examples include electromagnetic fields (radiated emissions), electrostatic discharges, and conducted emissions.
ELECTROMAGNETIC INTERFERENCE (EMI) - degradation of the performance of a piece of equipment, transmission channel, or system (e.g., medical devices) caused by an electromagnetic disturbance.
ELECTROSTATIC DISCHARGE - the rapid transfer of electrostatic charge between bodies of different electrostatic potential, either in proximity in air (air discharge) or through direct contact (contact discharge).
EMC - See Electromagnetic Compatibility.
EMD - See Electromagnetic Disturbance.
EMI - See Electromagnetic Interference.
CONDUCTED EMISSIONS - electromagnetic energy introduced into a product through a conductor by means of resistance, inductance or capacitance. Conductors include AC power cords, metallic enclosures of a subsystem, or cables interconnecting subsystems or the patient to the product. Conducted emissions include power line anomalies, harmonics, surges, EFTs (electrical fast transients), and radiofrequencies, especially 150kHz to 80 MHz.
RADIATED EMISSIONS - electromagnetic energy emanating from a device and propagating through space or a medium (which can affect the distance and direction of propagation).
ESD - See Electrostatic Discharge.
IMMUNITY - the ability of an electrical or electronic product to operate as intended without performance degradation in the presence of an electromagnetic disturbance.
RECALL - a firm's removal or correction of a marketed product that (1) the FDA considers to be inviolation of the laws it administers and against which the FDA would initiate legal action or (2) where the FDA finds that there is a reasonable probability that the device would cause serious, adverse health consequences or death. This is contrasted with a device upgrade, defined below.
RADIOFREQUENCY - a frequency in the portion of the electromagnetic spectrum that is between the audio and the infrared portions. Commonly used radio frequencies range from 9 kHz to 100 GHz.
RFI - Radio Frequency Interference; one type of EMD, resulting from radiated emissions from broadcast antennas or electronic emitters.
SUSCEPTIBILITY - the potential for equipment (e.g. devices) to respond to an electromagnetic disturbance.
UPGRADE - an action taken voluntarily by a device manufacturer to improve or enhance the performance or safety of a device when there is no violation of the FD&C Act and it would not cause serious, adverse health consequences or death. An upgraded device would still perform as it was originally designed and labeled to do, in accordance with its premarket clearance specifications. The design change may be brought about due to user recommendations, improved technology, compliance with government or industry standards, or may be a natural evolutionary development. A product upgrade may or may not result in the return of the device to a facility to institute the retrofit/upgrade.
VULNERABILITY - See susceptibility.