Sources of Electromagnetic Interference (EMI) at a Call Center. Finding and assessing electromagnetic fields (EMF) in the workplace. The affect of EMI on medical implants and a Programmable Hydrocephalus Shunt Valve.

1. MAY 23-25 | Nashville, TN | 1
Sources of Electromagnetic Interference (EMI)
at a Call Center
Stuart D Bagley, MS, CIH, CSP,
President,
IAQ-EMF Consulting Inc.

2. • IAQ-EMF Consulting Inc.
• President, 23 years
• Boynton Beach, Florida
• (800) 862-9655
• We serve the entire USA
MAY 23-25 | Nashville, TN | 2
Stuart D Bagley, MS, CIH, CSP

3. MAY 23-25 | Nashville, TN | 3
My Bio
Stuart D Bagley, MS, CIH, CSP
❖President of IAQ-EMF Consulting Inc (23 years)
❖30 years as an Industrial Hygienist
❖Compliance Officer for US-OSHA
❖EHS Manager General Electric Power Generation
❖EHS Manager General Dynamics Land Systems
❖EHS Manager Tenneco Packaging

4. MAY 23-25 | Nashville, TN | 4
An employee works at a call center in an office building
The Employee suffers from a condition known as Hydrocephalus

5. MAY 23-25 | Nashville, TN | 5
This drawing shows the medical condition known as
Hydrocephalus
Hydrocephalus is the buildup of fluid in the cavities (ventricles)
deep within the brain.

6. MAY 23-25 | Nashville, TN | 6
Treatment for Hydrocephalus
The most common treatment for hydrocephalus is the surgical
insertion of a drainage system, called a shunt. It consists of a long,
flexible tube with a valve that keeps fluid from the brain flowing in
the right direction and at the proper rate.

7. MAY 23-25 | Nashville, TN | 7
A Programmable Hydrocephalus Shunt
Valve looks like this…
These valves are
designed to be
adjusted by a
strong magnetic
field applied
externally.

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➢A Programmable Shunt
is subject to magnetic
field interference~~~.
➢Magnetic field
interference may cause
unintended changes to
the shunt valve settings
Magnetic Field Interference

9. MAY 23-25 | Nashville, TN | 9
The shunt valve is placed in areas within the patient’s
brain to regulate Cerebrospinal Fluid
Programmable Shunt Valve

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Electromagnetic Interference (EMI)
There were indications of electromagnetic interference
(EMI) with this device reported by his doctor.

11. MAY 23-25 | Nashville, TN | 11
Electromagnetic Interference (EMI)
Electromagnetic interference (EMI) is a
phenomenon that may occur when an electronic
device is exposed to an electromagnetic field. Any
device that has electronic circuitry can be
susceptible to EMI. This includes a programmable
hydrocephalus shunt.
)

12. MAY 23-25 | Nashville, TN | 12
Areas We Tested at the Call Center
✓ General Area
✓ Telephone
✓ Employee Headset
✓ Executive Kitchen
✓ Outside West
✓ Break Room
✓ Office 438
✓ VP Office
✓ East Wing
✓ East Main Corridor
✓ Lake Erie
✓ Conference Room
✓ Market OPS (5)
✓ SW Corner
✓ Analyst Area
✓ West Wing Corridor
✓ Main Reception
✓ Main Reception
✓ Office 429
✓ Outside North
✓ Outside East
✓ Outside South

13. • Hand Tools
• Cell Phones
• Tablet Devices
• Metal Detectors
• High Voltage Overhead Powerlines (> 480 Volts)
• Call Center Headphones
• Electronic Card Reader
• Microwave Ovens
MAY 23-25 | Nashville, TN | 13
Sources of Interference We Tested
at the Call Center

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Potential Sources of Electromagnetic
Interference (EMI)
Cell Phones

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Potential Sources of Electromagnetic
Interference (EMI)
Microwave
Oven

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Potential Sources of Electromagnetic
Interference (EMI) at a Call Center
Electrical Substation
Near the Call Center
Building seen from a
Window

17. MAY 23-25 | Nashville, TN | 17
Potential Sources of Electromagnetic
Interference (EMI)
Electronic Card Reader

18. MAY 23-25 | Nashville, TN | 18
Potential Sources of Electromagnetic
Interference (EMI)
Call Center
Employee
Headphone

19. MAY 23-25 | Nashville, TN | 19
What is the magnet in a an employee
headphone?
Embedded Magnet
Most headphones and earbuds have a magnet in them which can
affect an implanted device. The magnet and coil produce sound.

20. MAY 23-25 | Nashville, TN | 20
General Area
Specific
Location
Field
Measured:
P, RF Measurement Maximum Units
Exceeds
Published
Guidelines
Telephone
Headset
Earpiece
(foam side) P 0 inches 156 G Yes Pub 1
Telephone
Headset
Earpiece
(microphone
side) P 0 inches 10 G Yes
Executive
Kitchen
Frigidaire
Microwave RF 0 inches 2,720.0 V/m Yes
Executive
Kitchen
Frigidaire
Microwave RF 12 inches 1,535.0 V/m Yes
Executive
Kitchen
Frigidaire
Microwave RF 24 inches 107.1 V/m Yes
Outside West
Far South
Parking Lot
under Powerline E 24 ft. 6,900.0 V/m Yes
Break Room
FFCM 113415
Frigidaire
Microwave RF 0 inches 265.7 V/m Yes
Review of the EMI Data
• Publication 1: "Electromagnetic field hazards involving adjustable shunt valves in hydrocephalus" J Neurosurg., 2002 Feb
• Publication 2: "Magnetic field interactions in adjustable hydrocephalus shunts", Journal of Neurosurgery: Pediatrics, September 2008,
• HD: Implanted Heart Device

21. MAY 23-25 | Nashville, TN | 21
The headset is the most likely source of EMI ~~~
Magnetic field of 156
Gauss at the earpiece
exceeds a known
harmful limit

22. MAY 23-25 | Nashville, TN | 22
Magnetic Field Interference with Programmable CSF
Shunts
“People implanted with magnetic externally programmable CSF
shunt valves may have risk of experiencing an unintended
change in their valve setting when exposed to strong magnetic
fields from external magnetic sources…”
US FDA, Magnetic Field Interference with Programmable CSF Shunts, 2019

23. MAY 23-25 | Nashville, TN | 23
US FDA Recommendations
The US FDA suggests keeping products that contain
magnets two or more inches away from the location of
magnetic externally programmable CSF shunt valves.

24. MAY 23-25 | Nashville, TN | 24
One Solution: Use a Non-Magnetic Employee Headphone

25. MAY 23-25 | Nashville, TN | 25
How does it work?
Piezoelectric Headphones Do Not Have a Magnet
Instead a piezoelectric earphone produces sound by using a
piezoelectric crystal, a material that changes its shape when
electricity is applied to it and produces sound.

26. MAY 23-25 | Nashville, TN | 26
Stuart D Bagley, MS CIH CSP
IAQ-EMF Consulting Inc.
sbagley@emftesting.net
(800) 862-9655
The source of EMI was found.
Problem Solved!