Thisvehiclehasanimmunitylevelof 20v/mwhichshouldprotectitfrom
ElectromagneticInterference(EMI)from
Radio
Wave
SourcesTherapid
developmentofelectronics,especiallyintheareaof communications,has
saturatedourenvironment
with
electromagnetic(radio)wavesthatareemitted
bytelevision,radioandcommunicationsignals.
These
EMwavesareinvisible
andtheirstrengthincreasesasoneapproachesthesource.Allelectrical
conductorsactasantennastotheEMsignalsand,tovaryingdegrees,allpower
wheelchairsandscootersaresusceptibletoelectromagneticinterference
(EMI).
Thisinterferencecouldresultinabnormal,unintentionalmovementand/orerratic
control
ofthevehicle.TheUnitedStates
Food
and
Drug
Administration(FDA)
suggeststhatthefollowingstatementbeincorporatedtotheuser'smanualforall
electhc
scooters:
Poweredwheelchairsandelectricscooters(inthis
text,
both
will
bereferredtoas
poweredwheelchairs)maybesusceptibletoelectromagneticinterference
(EMI),
which
is interferingelectromagneticenergyemittedfromsourcessuchasradio
stations,
TVstations,amateurradio(HAM)transmitters,two-wayradiosand
cellular
phones.Theinterference(fromradiowavesources)cancausethe
poweredwheelchairtoreleaseitsbrakes,
move
by
itself
or
move
inunintended
directions.
Itcanalsopermanently
damage
thepoweredwheelchair'scontrol
system.TheintensityoftheEMenergycanbemeasuredinvoltspermeter
(V/m).
Each
poweredwheelchaircanresistEMIuptoa certainintensity.Thisis
called
the"immunitylevel."Thehighertheimmunitylevel,thegreaterthe
protection.
Atthistime,currenttechnologyiscapableofprovidingatleast20V/m
ofimmunitylevelwhichwouldprovideusefulprotectionagainstcommonsources
ofradiatedEMI.
Followingthewarningslistedbelowshouldreducethechanceofunintended
brakereleaseorpoweredwheelchairmovementthatcouldresultinserious
injury:
1)Donotturnonhand-heldpersonalcommunicationdevicessuchascitizens
band
(CB)radiosandcellular
phones
whilethepoweredwheelchairis turned
on.
2)BeawareofnearbytransmitterssuchasradioorTVstationsandtrytoavoid
comingclosetothem.