A practical procedure to prevent electromagnetic interference with electronic medical equipment
Hanada E, Takano K, Antoku Y, Matsumura K, Watanabe Y, Nose Y
J Med Syst 26(1):61-65, 2002
Problems involving electromagnetic interference (EMI) with electronic medical equipment are well-documented. However, no systematic investigation
of EMI has been done.
We have systematically investigated the causes of EMI.
The factors involved in EMI were determined as follows:
intensity induced by invasive radio waves from outside a hospital.
Residual magnetic-flux density at welding points in a building.
Electric-field intensity induced by conveyance systems with a linear motor.
4) The shielding capacity of hospital walls.
5) The shielding capacity of
commercial shields against a wide range frequency radio waves.
immunity of electronic medical equipment.
7) EMI by cellular telephone and
personal handy-phone system handsets.
From the results of our investigation,
we developed a following practical procedure to prevent EMI.
of electric-field intensity induced by invasive radio waves from outside the
hospital and industrial systems in the hospital.
2) Measurement of residual
magnetic-flux density at electric welding points of hospital buildings with
steel frame structures.
3) Control of the electromagnetic environment by
utilizing the shielding capacity of walls.
4) Measurement of the immunity of
electronic medical equipment. And
5) Installation of electronic gate
equipment at the building entrance to screen for handsets.