582 6-1. Specifications
Tire related termMeaning
PlyA layer of rubber-coated parallel cords
Ply separationA parting of rubber compound between
adjacent plies
Pneumatic tire
A mechanical device made of rubber,
chemicals, fabric and steel or other materials,
that, when mounted on an automotive wheel,
provides the traction and contains the gas or
fluid that sustains the load
Radial ply tire
A pneumatic tire in which the ply cords that
extend to the beads are laid at substantially 90
degrees to the centerline of the tread
Reinforced tire
A tire designed to operate at higher loads and
at higher inflation pressures than the
corresponding standard tire
Section width
The linear distance between the exteriors of
the sidewalls of an inflated tire, excluding
elevations due to labeling, decoration, or
protective bands
SidewallThat portion of a tire between the tread and
bead
Sidewall separationThe parting of the rubber compound from the
cord material in the sidewall
Snow tire
A tire that attains a traction index equal to or
greater than 110, compared to the ASTM E-
1136 Standard Reference Test Tire, when
using the snow traction test as described in
ASTM F-1805-00, Standard Test Method for
Single Wheel Driving Traction in a Straight Line
on Snow-and Ice-Covered Surfaces, and which
is marked with an Alpine Symbol ( ) on at
least one sidewall
Te s t r i m
The rim on which a tire is fitted for testing, and
may be any rim listed as appropriate for use
with that tire
