Over the past 2 decades, there has been remarkable growth in the sources of RF energy. Twenty years ago, people did not have cell phones, pagers, or laptop computers with wireless modems installed.Over the years, many incidents of suspected electromagnetic interference (EMI) with medical devices have been documented. Defibrillators are one type of medical implant that has had problems due to electromagnetic interference that has been well-documented in medical journals. There is increased concern for the safe and effective use of devices in an environment that has become crowded with potential sources of electromagnetic interference (EMI).
Because of its concern for public health and safety, the Center for Devices and Radiological Health (CDRH), which is part of the Food and Drug Administration (FDA), in the US, has been at the forefront of examining medical device electromagnetic interference and providing solutions. Extensive laboratory testing by CDRH and others has revealed that many medical devices can be susceptible to problems caused by EMI.
According to the CDRH, the key to addressing electromagnetic interference (EMI) is the recognition that it involves not only the device itself, but also the environment in which it is used, and anything that may come into that environment. More than anything else, the concern with EMI must be viewed as a systems problem requiring a systems approach. In this case, the solution requires the involvement of the medical device industry, the EM source industry (e.g., power industry, telecommunications industry), and the clinical user and patient.
The public must also play a part in the overall approach to recognizing and dealing with EMI. Electromagnetic compatibility, or EMC, is essentially the opposite of EMI. EMC means that the device is compatible with (i.e., no interference caused by) its EM environment, and it does not emit levels of EM energy that cause EMI in other devices in the vicinity. The wide variation of medical devices and use environments makes them vulnerable to different forms of EM energy which can cause EMI: conducted, radiated, and electrostatic discharge (ESD). Further, EMI problems with medical devices can be very complex, not only from the technical standpoint but also from the view of public health issues and solutions.
It is important to make sure you have the right kind of EMI/RFI filtering for your medical devices and hospital equipment. RFI filters play an especially important role in high-frequency and medical equipment applications. The typical frequency filtered is 10,000Hz to 30,000,000Hz for noise picked up and conducted through external wires or power cords. 30,000,000Hz to 1GHz is the frequency filtered for noise that is radiating and being picked up through the air. Low-leakage filters are used for medical equipment and devices, as they provide low levels of leakage current to meet patient safety requirements.
Electromagnetic interference (EMI) and Radio Frequency interference (RFI) are disturbances that can affect the electrical circuit because of electromagnetic induction or electromagnetic radiation from external sources. These disturbances can interrupt, degrade and/or limit the performance of the circuit itself. Many countries have requirements for products to meet Electromagnetic Compatibility (EMC) standards.
MedWOW, the multilingual global medical equipment platform, offers medical equipment professionals a selection of RFI filters for a variety of different devices. If there is a particular RFI filter or part that you can’t find in MedWOW’s international inventories, you can post an RFI filter request or take advantage of MedWOW’s efficient part finder service. Currently filters are available from Siemens, GE Healthcare, Philips and more.
