Wireless Interference in Ambulance Causes Death

Wireless or electromagnetic interference (EMI) can disable life-saving medical equipment.

In one recent case, a heart attack victim was attached to a monitor/defibrillator on her way to the hospital. Unfortunately, the machine shut down every time the technician turned on the ambulance's radio transmitter to ask hospital staff for advice. As a result, the woman died.

Analysis showed that the ambulance's metal roof was recently replaced with fiberglass.  Additionally, the ambulance's radio was fitted with a new high-power, long-range antenna.

These two seemingly unrelated changes, taken together, had a catastrophic effect. The reduced shielding of the fiberglass roof, along with the strong radiated signal from the new antenna, was too much for the monitor/defibrillator to handle. The machine succumbed to the radio's electromagnetic interference (EMI). The patient died.

Problems like these can be avoided by consulting with an EMI expert before making substantial changes that could affect an electromagnetic environment.

EMI is complex. It can also be dangerous. Many factors can affect the level of interference. Additional factors can affect the impact of that interference. 

Discovery Engineering leads EMI investigations and helps clients understand how EMI may or may not relate to a specific case.  Learn more at www.DiscoveryEngineering.net.

(Originally reported in the Wall Street Journal)