Banana Skins – July 2023 (#429-432)

429. Interference with critical auto systems

One car manufacturer found that the craze for CB radio caused more than a jamming of the airwaves. They found that if a CB was operated in close proximity to their car, the central locking engaged, locking the passengers within the vehicle! On a slightly more serious note, another prestige car manufacturer found that whenever the vehicle passed by an operating ambulance or fire station, the air bags activated.

(Extract from “Critical Nature of EMC,” Schaffner, Components in Electronics, May 2000, page 22.)

430. Mobile threat to drivers

Mobile phone makers and car manufacturers are investigating claims that handsets can cause car safety airbags to inflate and interfere with automatic braking systems. Tests carried out by Volvo in Sweden found that phones operating independently of car electrics can trigger airbags and interfere momentarily with control systems.

(Extracts from: “Mobile Threat to Drivers,” Computer Weekly, August 12, 1993, page 1.)

431. Interference examples from 1996

• A semi-submersible oil exploration platform moving off-station when its global positioning by satellite system was disrupted by the signal from a portable radio. This was due to poor shielding on an interconnection cable.
• Police cars’ central locking systems operating during use of their mobile radios.
• Vehicle anti-lock braking devices operating when a radio transmitter beaming across a highway five miles away, was used.
• A fatality when electromagnetic interference (EMI) caused a computer-controlled crane to drop its load.
• Two fatalities when robots went out of control in a factory.
• Failure of a portable gas detector, monitoring toxic gases while personnel repaired a sewer, when a hand-portable radio was used near it.
• Proximity devices operating due to EMI.
• A train operated abnormally when its rear locomotive developed a computer fault which caused it to be affected by radio emissions as it passed an airport (18^th September 1995, 06:45, Birmingham New Street to London Euston).
• A ladle making an incorrect stroke and burning a die-casting machine operator, possibly caused by EMI.
• A radio controlled crane going out of control, possibly due to EMI.
• An electron beam welding machine interfering with radio transmissions.
• A computer-aided drawing system malfunctioning because of electric trains three miles away.
• A hydraulic pump in a nearby building causing errors in a tensile testing machine.
• An expensive process shutting down due to the use of an X-ray techniques in a nearby building site to monitor the quality of welded pipes.
• Nearby fluorescent luminaires affecting the operation of radio receiving equipment. 
• A PC network regularly ‘crashed’ at dusk, found to be due to the switching on of nearby fluorescent street lighting.
• ‘And then there was the North Sea oil platform whose IT systems crashed on random occasions throughout the day for no apparent reason. The problem there was identified as visiting helicopters, the rotor blades of which were acting as giant Van Der Graff generators, accumulating enormous static charges that were discharged on landing.’¹¹

(Extracts from “Coping with the EMC Regulations,” P. Ridley, IEEE Engineering Management Journal, April 1996, page 101. Some of these incidents have also been reported by others in other Banana Skins.)

432. Pacemakers unaffected by stun guns

According to a study carried out by the Cleveland Clinic and published in Eurospace by the European Society of Cardiology®, a standard electrical discharge from a TASER® X26 electronic control device or stun gun, does not affect the integrity of implantable pacemakers and defibrillators and did not trigger an implanted cardioverter defibrillator (ICD) shock in devices programmed to the standard non-committed shock delivery mode.

The impact of electromagnetic interference on cardiac devices has been a long-standing concern and, in some instances, has been known to cause damage to internal circuitry, over-sensing, under-sensing, failure to pace, failure to capture, triggering of elective placement indicators, and inappropriate defibrillation shocks.

(Extracts from: “Study: Pacemakers Unaffected by Energy from Stun Guns,” EMC News, Interference Technology, May 2007.)  

The regular “Banana Skins” column was published in the EMC Journal, starting in January 1998. Alan E. Hutley, a prominent member of the electronics community, distinguished publisher of the EMC Journal, founder of the EMCIA EMC Industry Association and the EMCUK Exhibition & Conference, has graciously given his permission for In Compliance to republish this reader-favorite column. The Banana Skin columns were compiled by Keith Armstrong, of Cherry Clough Consultants Ltd, from items he found in various publications, and anecdotes and links sent in by the many fans of the column. All of the EMC Journal columns are available at: https://www.emcstandards.co.uk/emi-stories, indexed both by application and type of EM disturbance, and new ones have recently begun being added. Keith has also given his permission for these stories to be shared through In Compliance as a service to the worldwide EMC community. We are proud to carry on the tradition of sharing Banana Skins for the purpose of promoting education for EMI/EMC engineers.