Broadcast and wireless communications facilities are designed to minimize the RF power density in uncontrolled areas. However, the equipment that reads the increasingly popular RFID tags (those large loops on either side of the exits at many stores or panel antenna in “EzPass” lanes at toll booths) must illuminate the tag with RF in order to read it. The amount of RF used to read the tags is small, but there is concern it could interfere with the operation of medical devices.
RF safety expert Richard Strickland has noted cases where these devices interfered with pacemakers. You may be surprised to learn that there is currently no published, standardized, repeatable methodology that RFID equipment or medical device manufacturers can use to assess the impact electromagnetic interference on these devices.
The Georgia Tech Research Institute recently began developing testing protocols for RFID technology in the health care setting. AIM Global, the international trade association representing automatic identification and mobility technology solution providers is overseeing test protocol development.
“A comprehensive set of test protocols, which are sufficiently precise to permit repeatable results, is required to understand if there is an interaction between various types of RFID systems and active implantable medical devices, electronic medical equipment, in vitro diagnostic equipment and biologics,” said Craig K. Harmon, president and CEO of Q.E.D. Systems and chairman of AIM Global's RFID Experts Group. “Only after the protocols are developed will we be able to investigate the cause of any interactions, the result of any interactions, and ways manufacturers might eliminate or mitigate interactions.”
The director of the Georgia Tech Research Institute’s Medical Device Test Center, Ralph Herkert, observed that no since no two medical devices are constructed in the same manner, their response to external electromagnetic fields can be quite different.
“The internal components, firmware and hardware of every company’s devices are different, meaning that each device can respond differently to the same electromagnetic environment,” Herkert said. “Since there have been various preliminary tests and publications from different organizations indicating that there may or may not be issues with RFID system environments and these devices, it is important to standardize the way to test such devices.”
More information is available in the Georgia Tech Research news release.
As Richard Strickland points out in his RF Safety seminars, broadcasters need to be aware that RF can interfere with medical devices and take steps to make sure employees and visitors using medical devices are not harmed. Do you know which employees use medical devices that could be affected by RF? Here’s another tip: should you see someone collapse when walking between the RFID loops at store, the first response should be to pull them away from the loops.
