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for all scooters like the PT7 and PF7. Motorized scooters 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 and cellular phones. The
interference (from radio wave sources) can cause the powered wheelchair 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.
TURN OFF YOUR POWERED SCOOTER AS SOON AS POSSIBLE WHEN EXPERIENCING
THE FOLLOWING:
‧ Unintentional scooter movements
‧ Unintended or uncontrollable direction.
‧ Unexpected brake release
The FDA has written to the manufacturers of power scooters asking them to test new products to be
sure they provide a reasonable degree of immunity against EMI. The FDA requires that a powered
wheelchair should have an immunity level at least 20 V/m, which provides a reasonable degree of
protection against more common sources of EMI. The higher the immunity level, the greater the
protection. Your powered scooter has an immunity level of 20 V/m which should protect against
common sources of EMI.
