Electromagnetic Interference (Emi) From Radio Wave Sources - Heartway Medical Products HP7K User Manual

General
12. Always use a seat belt, and keep feet on the footplate at all the time.
13. For safety reasons, make sure that your weight does not exceed the recommended weight limit of
the wheelchair. Consult your dealer for the specified weight limits for your particular model.
14. Do not attempt to lift or move a power chair by any of its removable parts. Personal injury and
damage to the power chair may result.
15. Do not stand on the footplate directly.
16. Never try to use your wheelchair beyond its limitations as described in this manual.
17. Do not operate your vehicle if it is not functioning properly.
18. Do not connect any electrical or mechanical device to the vehicle. Failure to obey this instruction
may result in injury and will void the warranty.
19. Never use electronic radio transmitters such as CB, walkie -talkies, portable computers or
cellular phones while using the vehicle without first turning the vehicle off.
Use While Under the Influence Of Medication Or Alcohol
20. Check with your physician if you are taking any medication that may affect your ability to
operate your power wheelchair safely.
21. Do not operate your vehicle while you are under the influence of alcohol, as this may impair your
ability to operate your power chair in a safe manner.

Electromagnetic interference (EMI) from Radio Wave Sources

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 approaches
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 wheelchairs like the HP-7S. Power wheelchairs and
motorized scooters (in this section, both will be referred to as powered wheelchairs) 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 wheelchair's control system. The intensity of the EM energy can
be measured in volts per meter (V/m).Each powered wheelchair can resist EMI up to a certain
intensity. This is called "immunity level". The higher the immunity level is, the greater the protection
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