Bead means that part of the tire made of steel wires, wrapped or reinforced by ply cords, that is shaped to fit the rim.
Bead separation means a breakdown of bond between components in the bead area.
Bias ply tire means a pneumatic tire in which the ply cords that extend to the beads are laid at alternate angles substantially less than 90° to the centerline of the tread.
Carcass means the tire structure, except tread and sidewall rubber.
Chunking means the breaking away of pieces of the tread or sidewall.
Cord means the strands forming the plies in the tire.
Cord separation means cords parting away from adjacent rubber compounds.
Cracking means any parting within the tread, sidewall, or innerliner of the tire extending to cord material.
Groove means the space between two adjacent tread ribs.
Innerliner means the layer(s) forming the inside surface of a tubeless tire that contains the inflating medium within the tire.
Innerliner separation means the parting of the innerliner from cord material in the carcass.
Load rating means the maximum load a tire is rated to carry for a given inflation pressure.
Maximum permissible inflation pressure means the maximum cold inflation pressure to which a tire may be inflated.
Maximum load rating means the load rating at the maximum permissible inflation pressure for that tire.
Open splice means any parting at any junction of tread, sidewall, or innerliner that extends to cord material.
Overall width means the linear distance between the exteriors of the sidewalls of an inflated tire, including elevations due to labeling, decorations, or protective bands or ribs.
Ply means a layer of rubber-coated parallel cords.
Ply separation means a parting of rubber compound between adjacent plies.
Pneumatic tire means a mechanical device made of rubber, chemicals, fabric and steel or other materials, which, when mounted on an automotive wheel, provides the traction and contains the gas or fluid that sustains the load.
Radial ply tire means a pneumatic tire in which the ply cords which extend to the beads are laid at substantially 90° to the centerline of the tread.
Rim means a metal support for a tire or a tire and tube assembly upon which the tire beads are seated.
Section width means the linear distance between the exteriors of the sidewalls of an inflated tire, excluding elevations due to labeling, decoration, or protective bands.
Sidewall means that portion of a tire between the tread and the bead.
Sidewall separation means the parting of the rubber compound from the cord material in the sidewall.
Test rim means, with reference to a tire to be tested, any rim that is listed as appropriate for use with that tire in accordance with S4.4. For purposes of this section and § 571.110 , each rim listing shall include dimensional specifications and a diagram of the rim.
Tread means that portion of a tire that comes into contact with the road.
Tread rib means a tread section running circumferentially around a tire.
Tread separation means pulling away of the tread from the tire carcass.
Tire and Rim Association
The European Tyre and Rim Technical Organization
Japan Automobile Tyre Manufacturers Association, Inc.
Tyre and Rim Association of Australia
Associacao Latino Americana de Pneus e Aros (Brazil)
South African Bureau of Standards
W=[(F * P)/2] * 10*3 (joules)
Where
W = Energy, in joules;
F = Force, Newtons; and
P = Penetration, mm; or
W=[(F * P)/2]
Where
W = Energy, inch-pounds;
F = Force, pounds; and
P = Penetration, inches.
The loads for the following periods are the specified percentage of the maximum load rating marked on the tire sidewall:
Percent | |
4 hours | 85 |
6 hours | 90 |
24 hours | 100 |
Figures for FMVSS No. 109
Wheel size | Dimension "A" for tires with maximum inflation pressure | |||
Other than 60 psi (in) | Other than 420 kPa | 60 psi (in) | 420 kPa | |
20 | 13.50 | 345 | ||
19 | 13.00 | 330 | 12.00 | 305 |
18 | 12.50 | 318 | 11.40 | 290 |
17 | 12.00 | 305 | 10.60 | 269 |
16 | 11.50 | 292 | 9.90 | 251 |
15 | 11.00 | 279 | 9.40 | 239 |
14 | 10.50 | 267 | 8.90 | 226 |
13 | 10.00 | 254 | 8.40 | 213 |
12 | 9.50 | 241 | ||
11 | 9.00 | 229 | ||
10 | 8.50 | 216 | ||
320 | 8.50 | 216 | ||
340 | 9.00 | 229 | ||
345 | 9.25 | 235 | ||
365 | 9.75 | 248 | ||
370 | 10.00 | 254 | ||
390 | 11.00 | 279 | ||
415 | 11.50 | 292 |
Appendix A-Federal Motor Vehicle Safety Standard No. 109
The following tables list tire sizes and tire constructions with proper load and inflation values. The tables group tires of related constructions and load/inflation values. Persons requesting the addition of new tire sizes to the tables or the addition of tables for new tire constructions may, when the additions requested are compatible with existent groupings, or when adequate justification for new tables exists, submit five (5) copies of information and data supporting the request to the Vehicle Dynamics Division, Office of Crash Avoidance Standards, National Highway Traffic Safety Administration, 400 Seventh Street SW., Washington, DC 20590.
The information should contain the following:
Table I-A-For Bias Ply Tires With Designated Section Width of 152 mm (6 Inches) and Above
Cord material | 32 psi | 36 psi | 40 psi | 240 kPa | 280 kPa | 300 kPa | 340 kPa |
Rayon: | |||||||
(in-lbs) | 1,650 | 2,574 | 3,300 | 1,650 | 3,300 | 1,650 | 3,300 |
(joules) | 186 | 291 | 373 | 186 | 373 | 186 | 373 |
Nylon or polyester: | |||||||
(in-lbs) | 2,600 | 3,900 | 5,200 | 2,600 | 5,200 | 2,600 | 5,200 |
(joules) | 294 | 441 | 588 | 294 | 588 | 294 | 588 |
Table I-B-For Bias Ply Tires With Designated Section Width Below 152 mm (6 Inches)
Cord material | 32 psi | 36 psi | 40 psi | 240 kPa | 280 kPa | 300 kPa | 340 kPA |
Rayon: | |||||||
(in-lbs) | 1,000 | 1,875 | 2,500 | 1,000 | 2,500 | 1,000 | 2,500 |
(joules) | 113 | 212 | 282 | 113 | 282 | 113 | 282 |
Nylon or polyester: | |||||||
(in-lbs) | 1,950 | 2,925 | 3,900 | 1,950 | 3,900 | 1,950 | 3,900 |
(joules) | 220 | 330 | 441 | 220 | 441 | 220 | 441 |
Table I-C-For Radial Ply Tires
Size designation | Maximum permissible inflation | |||||||
PSI | kPa | |||||||
32 | 36 | 40 | 240 | 280 | 300 | 340 | 350 | |
Below 160 mm: | ||||||||
(in-lbs) | 1,950 | 2,925 | 3,900 | 1,950 | 3,900 | 1,950 | 3,900 | 1,950 |
(joules) | 220 | 330 | 441 | 220 | 441 | 220 | 441 | 220 |
160 mm or above: | ||||||||
(in-lbs) | 2,600 | 3,900 | 5,200 | 2,600 | 5,200 | 2,600 | 5,200 | 2,600 |
(joules) | 294 | 441 | 588 | 294 | 588 | 294 | 588 | 294 |
Table I-D-For Tires With 420 kPa (60 psi) Maximum Permissible Inflation Pressure and Maximum Load Rating 399 kg (880 lb) and Above
Cord material | Inch-pounds joules (J) |
Rayon | 1,650 inch pounds 186 joules (J). |
Nylon or Polyester | 2,600 inch pounds 294 joules (J). |
Table I-E-For Tires With 420 kPa (60 psi) Maximum Permissible Inflation Pressure and Maximum Load Rating Below 399 kg (880 lb)
Cord material | Inch-pounds joules (J) |
Rayon | 1,000 inch pounds 113 joules (J). |
Nylon or Polyester | 1,950 inch pounds 220 joules (J). |
Table II-Test Inflation Pressures
[Maximum permissible inflation pressure to be used for the following test]
Test type | psi | kPa | |||||||
32 | 36 | 40 | 60 | 240 | 280 | 300 | 340 | 350 | |
Physical dimensions | 24 | 28 | 32 | 60 | 180 | 220 | 180 | 220 | 180 |
Bead unseating, tire strength, and tire endurance | 24 | 28 | 32 | 52 | 180 | 220 | 180 | 220 | 180 |
High speed performance | 30 | 34 | 38 | 58 | 220 | 260 | 220 | 260 | 220 |
Appendix to § 571.109
Persons requesting the addition of new tire sizes not included in S4.4.1(b) organizations may, upon approval, submit five (5) copies of information and data supporting the request to the Vehicle Dynamics Division, Office of Crash Avoidance Standards, National Highway Traffic Safety Administration, West Building, 1200 New Jersey Ave. SE., Washington, DC 20590.
The information should contain the following:
49 C.F.R. §571.109
For FEDERAL REGISTER citations affecting § 571.109, see the List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at www.govinfo.gov.