Responsible Wireless Communication

Picking up signals, and picking them up accurately, is the subject of much discussion these days. As wireless communication becomes more prevalent, it is imperative—especially in the medical field— that signals are not disrupted or corrupted. In health care facilities, where wireless transmissions provide physicians with critical patient information, accuracy is of the utmost importance. Wireless means freedom, but with freedom comes a responsibility to monitor systems and equipment to keep them secure and operating safely.

In November 2005, the United States FDA issued a notification regarding the increased risk of electromagnetic interference with medical telemetry systems operating in the 460–470 MHz frequency bands after December 31, 2005.

The FDA explained that in 2000, the FCC dedicated a portion of the radio spectrum for wireless medical telemetry. This part of the spectrum, known as the Wireless Medical Telemetry Service, included 608–614MHz, 1395–1400MHz, and 1427–1432 MHz bands. With a spectrum now designated for medical telemetry use, the FCC intended to grant new licenses to higher-power mobile radio users in the 460–470MHz band. Due to the potential for serious interference with existing medical telemetry systems, the FCC delayed implementing this change in order to allow time for medical facilities to move out of the 460–470MHz band.

This freeze expired on December 31, 2005. Most of the new radio users in this band will include handheld and other mobile transmitters, such as those operated by police; fire and rescue; taxis; and commercial trucks—all likely operators in and around hospitals.

According to tests conducted by the FDA, the transmitters operating in this frequency band can interfere with medical telemetry systems, which could lead to lapses in patient monitoring and missed alarm events, putting patients at risk. The anticipated interference will not be limited to urban areas, as any medical facility in the vicinity of a mobile radio could be affected.

Therefore, if health care facilities have not already addressed this potential problem, the FDA recommends numerous safeguards, including determining in which frequency your current wireless medical telemetry systems are operating; migrating out of the 460–470MHz band and moving to less vulnerable frequencies, such as the WMTS bands; and assessing and managing the risks for all medical telemetry systems.

As advanced technology increasingly surrounds us and we spend more of our time in front of computers, let’s not forget the ultimate examples of wireless communication—human beings. Even in the “wireless” communication between us all, there are plenty of opportunities for signal interference and misinterpretation, and it is up to each of us to keep the communication frequencies between us open and clear.

jkirst@ascendmedia.com