Electomagnetic Interference(Emi) - Heartway Medical Products S34 Pixi User Manual

ELECTROMAGNETIC INTERFERENCE (EMI)
The rapid development of electronics, especially in the area of communications, has saturated our environment
with electromagnetic (EM) radio waves that are emitted by television, radio and communication signals. These
EM wave are invisible and their strength increases as one approach the source. All electrical conductors act as
antennas to the EM signals and, to varying degrees, all power wheelchairs and scooters are susceptible to
electromagnetic interference (EMI). The interference could result in abnormal, unintentional movement and/or
erratic control of the vehicle. The United States Food and drug Administration (FDA) suggests that the
following statement be incorporated to the user's manual for all power scooter like the S34
may as susceptible to electromagnetic interference (EMI), which is interfering electromagnetic energy emitted
from sources such as radio stations, TV stations, amateur radio (HAN) transmitter, two-way radios, cellular
phones and alarm systems of shops. The interference (from radio wave sources) can cause the power scooter to
release its brakes, move by itself or move in unintended directions. It can also permanently damage the
powered scooter's control system. The intensity of the EM energy can be measured in volts per meter
(V/m).Each powered scooter can resist EMI up to a certain intensity. This is called "immunity level". The
higher the immunity level the greater the protection. At this time, current technology is capable of providing at
least 20 V/m of immunity level, which would provide useful protection against common sources of radiated
EMI.
Following the warnings listed below should reduce the chance of unintended brake release or powered scooter
movement that could result in serious injury:
1. Do not turn on hand-held personal communication devices such as citizens band (CB) radios and cellular
phones while the powered scooter is turned on.
2. Be aware of nearby transmitters such as radio or TV stations and try to avoid coming close to them.
3. If unintended movement or brake release occurs, turn the powered scooter off as soon as it is safe.
4. Be aware that adding accessories or components, or modifying the powered scooter, may make it more
susceptible to interference from radio wave sources (Note: It is difficult to evaluate the effect on the
overall immunity of the powered scooter).
5. Report all incidents of unintended movement or brake release to the powered scooter manufacturer, and
note whether there is a radio wave source nearby.
7
. Power scooters