Tire Safety Information
Load rating The maximum load that a tire is rated to carry for a given inflation
pressure.
Maximum load rating The load rating for a tire at the maximum permissible
inflation pressure for that tire.
Maximum permissible inflation pressure The maximum cold inflation pressure
to which a tire may be inflated.
Maximum loaded vehicle weight The sum of curb weight, accessory weight,
vehicle capacity weight, and production options weight.
Measuring rim The rim on which a tire is fitted for physical dimension
requirements.
Non-pneumatic rim A mechanical device which, when a non-pneumatic tire
assembly incorporates a wheel, supports the tire, and attaches, either integrally or
separably, to the wheel center member and upon which the tire is attached.
Non-pneumatic spare tire assembly A non-pneumatic tire assembly intended for
temporary use in place of one of the pneumatic tires and rims that are fitted to a
passenger car in compliance with the requirements of this standard.
Non-pneumatic tire A mechanical device which transmits, either directly or
through a wheel or wheel center member, the vertical load and tractive forces from
the roadway to the vehicle, generates the tractive forces that provide the directional
control of the vehicle and does not rely on the containment of any gas or fluid for
providing those functions.
Non-pneumatic tire assembly A non-pneumatic tire, alone or in combination with
a wheel or wheel center member, which can be mounted on a vehicle.
Normal occupant weight This means 68 kilograms (150 lbs.) times the number
of occupants specified in the second column of Table I of 49 CFR 571.110.
Occupant distribution The distribution of occupants in a vehicle as specified in
the third column of Table I of 49 CFR 571.110.
Open splice Any parting at any junction of tread, sidewall, or innerliner that
extends to cord material.
Outer diameter The overall diameter of an inflated new tire.
Overall width The linear distance between the exteriors of the sidewalls of an
inflated tire, including elevations due to labeling, decorations, or protective bands
or ribs.
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