Regulation No. 30-02

Name:Regulation No. 30-02
Description:Tyres.
Official Title:Uniform Provisions Concerning the Approval of: Pneumatic Tyres for Motor Vehicles and their Trailers.
Country:ECE - United Nations
Date of Issue:1975-04-01
Amendment Level:02 Series, Supplement 18
Number of Pages:34
Vehicle Types:Car, Component, Light Truck, Trailer
Subject Categories:Steering, Wheels and Tyres
Available on InterRegs.NET

Our online subscription service, offering immediate access to our extensive library of global vehicle regulations, standards and legislation. A fully searchable, accurate, user-friendly resource for consolidated regulations that are updated quickly and frequently.

Tell me more | Already a subscriber

Available on SelectRegs.com

Our fast and easy means of purchasing up-to-date global vehicle and component standards and regulations on a pay-as-you-go basis. Pay securely by credit card and your documents are delivered directly and immediately to your computer as PDF files.

Tell me more | Go straight to site

Keywords:

tyre, speed, tyres, approval, regulation, test, load, maximum, paragraph, rim, means, diameter, type, series, annex, section, amendments, width, tread, manufacturer, supplement, nominal, symbol, date, force, rating, entry, case, designation, index, outer, category, flat, production, number, measuring, run, size, structure, temporary, equal, pressure, speeds, marking, requirements, diagonal, markings, conformity, approved, height

Text Extract:

All InterRegs documents are formatted as PDF files and contain the full text, tables, diagrams and illustrations of the original as issued by the national government authority. We do not re-word, summarise, cut or interpret the regulatory documents. They are consolidated, published in English, and updated on a regular basis. The following text extract indicates the scope of the document, but does not represent the actual PDF content.

E/ECE/324
) Rev.1/Add.29/Rev.3/Amend.4
E/ECE/TRANS/505 )
February 22, 2017
STATUS OF UNITED NATIONS REGULATION
ECE 30-02
UNIFORM PROVISIONS CONCERNING THE APPROVAL OF:
PNEUMATIC TYRES FOR MOTOR VEHICLES AND THEIR TRAILERS
Incorporating:
Supplement 9 to the 02 series of amendments
Date of Entry into Force: 06.02.99
Supplement 10 to the 02 series of amendments
Date of Entry into Force: 13.01.00
Corr. 1 to Supplement 10 to the 02 series of amendments
Dated: 13.05.04
Supplement 11 to the 02 series of amendments
Date of Entry into Force: 28.12.00
Supplement 12 to the 02 series of amendments
Date of Entry into Force: 20.02.02
Corr. 1 to Supplement 12 to the 02 series of amendments
Dated : 01.08.02
Supplement 13 to the 02 series of amendments
Date of Entry into Force: 26.02.04
Supplement 14 to the 02 series of amendments
Date of Entry into Force: 18.01.06
Supplement 15 to the 02 series of amendments
Date of Entry into Force: 10.11.07
Supplement 16 to the 02 series of amendments
Date of Entry into Force: 17.03.10
Supplement 17 to the 02 series of amendments
Date of Entry into Force: 27.01.13
Corr. 1 to Amendment 3 to Revision 3
Dated : 27.08.14
(Erratum by the Secretariat)
Supplement 18 to the 02 series of amendments
Date of Entry into Force: 09.02.17

REGULATION No. 30
UNIFORM PROVISIONS CONCERNING THE APPROVAL OF
PNEUMATIC TYRES FOR MOTOR VEHICLES AND THEIR TRAILERS
CONTENTS
REGULATION
1. Scope
2. Definitions
3. Markings
4. Application for Approval
5. Approval
6. Requirements
7. Modifications of the type of pneumatic tyre and extension of approval
8. Conformity of production
9. Penalties for non-conformity of production
10. Production definitely discontinued
11. Transitional provisions
12. Names and addresses of technical services responsible for conducting approval tests and of type
approval authorities
ANNEXES
Annex 1 –
Annex 2 –
Annex 3 –
Annex 4 –
Annex 5 –
Annex 6 –
Annex 7 –
Communication concerning the approval or extension or refusal or withdrawal of approval or
production definitely discontinued of a type of pneumatic tyre for motor vehicles pursuant to
Regulation No. 30
Example of the arrangement of the approval mark
Arrangement of tyre markings
Load-capacity indices
Tyre size designation and dimensions
Method of measuring pneumatic tyres
Procedure for load/speed performance tests

2.5. "Normal tyre" means a tyre intended for normal on-road use.
2.6. "Snow tyre" means a tyre whose tread pattern, tread compound or structure is primarily
designed to achieve in snow conditions a performance better than that of a normal tyre with
regard to its ability to initiate or maintain a vehicle motion.
2.7. "Special use tyre" means a tyre intended for mixed use both on- and off-road or for other
special duty. These tyres are primarily designed to initiate and maintain the vehicle in
motion in off-road conditions.
2.7.1. "Professional off-road tyre" is a special use tyre primarily used for service in severe
off-road conditions.
2.8. "Structure" of a tyre means the technical characteristics of the tyre's carcass. The following
structures are distinguished in particular;
2.8.1. "Diagonal" or "bias-ply" describes a tyre structure in which the ply cords extend to the
beads and are laid at alternate angles of substantially less than 90° to the centre line of the
tread;
2.8.2. "Bias-belted" describes a tyre structure of diagonal (bias-ply) type in which the carcass is
restricted by a belt comprising two or more layers of substantially inextensible cord material
laid at alternate angles close to those of the carcass;
2.8.3. "Radial" describes a tyre structure in which the ply cords extend to the beads and are laid
substantially at 90° to the centre line of the tread, the carcass being stabilised by an
essentially inextensible circumferential belt;
2.8.4. "Reinforced" or "Extra Load" means a tyre structure designed to carry more load at a
higher inflation pressure than the load carried by the corresponding standard version tyre at
the standard inflation pressure as specified in ISO 4000-1:2010;
2.8.5. "Temporary use spare tyre" means a tyre different from a tyre intended to be fitted to any
vehicle for normal driving conditions but intended only for temporary use under restricted
driving conditions;
2.8.6. "T-type temporary use spare tyre" means a type of temporary use spare tyre designed for
use at inflation pressures higher than those established for standard and reinforced tyres;
2.8.7. "Run flat tyre" or "Self supporting tyre" describes a tyre structure provided with any
technical solutions (for example, reinforced sidewalls, etc.) allowing the tyre, mounted on
the appropriate wheel and in the absence of any supplementary component, to supply the
vehicle with the basic tyre functions, at least, at a speed of 80km/h (50mph) and a distance
of 80 km when operating in flat tyre running mode.
2.9. "Bead" means the part of a tyre which is of such shape and structure as to fit the rim and
hold the tyre on it;
2.10. "Cord" means the strands forming the fabric of the plies in the tyre;

2.20.1. The values of the nominal rim diameters for code-designated rims expressed in millimetres
are shown below:
Nominal rim diameter code ("d" symbol)
Value of the "d" symbol expressed in mm
10 254
11 279
12 305
13 330
14 356
15 381
16 406
17 432
18 457
19 483
20 508
21 533
22 559
23 584
24 610
25 635
26 660
27 686
28 711
29 737
30 762
2.21. "Outer diameter" means the overall diameter of an inflated new tyre;
2.22. "Tyre-size designation" is
2.22.1. a designation showing:
2.22.1.1. the nominal section width. This width must be expressed in mm, except in the case of the
types of tyre for which the size designation is shown in the first column of the tables in
Annex 5 to this Regulation;
2.22.1.2. the nominal aspect ratio except in the case of certain types of tyre, for which the size
designation is shown in the first column of the tables in Annex 5 to this Regulation, or,
depending on the tyre design type, the nominal outer diameter expressed in mm;

2.34. "Speed category" means the maximum speed which the tyre can sustain, expressed by
speed category symbol (see table below).
2.34.1. The categories of speed are those indicated in the table below:
Speed-category symbol
L
M
N
P
Q
R
S
T
U
H
V
W
Y
Maximum speed (km/h)
120
130
140
150
160
170
180
190
200
210
240
270
300
2.35. Tread Pattern Grooves
2.35.1. "Principal grooves" means the wide circumference grooves positioned in the central zone
of the tyre tread, which have the tread-wear indicators located in the base.
2.35.2. "Secondary grooves" means the supplementary grooves of the tread pattern which may
disappear in the course of the tyre's life.
2.36. "Void to fill ratio" means the ratio between the area of voids in a reference surface and the
area of this reference surface calculated from the mould drawing.
2.37. "Maximum Load Rating" means the maximum mass the tyre is rated to carry;
2.37.1. for speed not exceeding 210km/h the maximum load rating shall not exceed the value
associated with the load capacity index of the tyre;
2.37.2. for speed higher than 210km/h, but not exceeding 240km/h, (tyres classified with Speed
Category Symbol "V") the maximum load rating shall not exceed the percentage of the value
associated with the load capacity index of the tyre, indicated in the table below, with
reference to the speed capability of the car to which the tyre is fitted.
Maximum speed (km/h) Maximum Load Rating (%)
215
220
225
230
235
240
98.5
97
95.5
94
92.5
91
For intermediate maximum speeds linear interpolations of the maximum load rating are
allowed.

2.39. "Basic tyre functions" means the normal capability of an inflated tyre in supporting a given
load up to a given speed and transmitting the driving, the steering and the braking forces to
the ground on which it runs.
2.40. "Run flat system" or "Extended mobility system" describes an assembly of specified
functionally dependant components, including a tyre, which together provide the specified
performance granting the vehicle with the basic tyre functions, at least, at a speed of 80km/h
(50mph) and a distance of 80 km when operating in flat tyre running mode.
2.41. "Deflected section height" is the difference between the deflected radius, measured from
the centre of the rim to the surface of the drum, and one half the nominal rim diameter as
defined in ISO 4000-1.
3. MARKINGS
3.1. Tyres submitted for approval shall bear on both side walls in the case of symmetrical tyres
and at least on the outer side wall in the case of asymmetrical tyres:
3.1.1. The manufacturer's name or the Brand name/trademark;
3.1.2. The trade description/commercial name (see Paragraph 2.4. of this Regulation). However,
the trade description is not required when it coincides with the Brand name/trademark.
3.1.3. The tyre-size designation;
3.1.4. An indication of the structure as follows;
3.1.4.1. on diagonal (bias-ply) tyres, no marking, or the Letter "D" placed in front of the rim diameter
marking;
3.1.4.2. on radial-ply tyres, the Letter "R" placed in front of the rim-diameter marking and, optionally,
the word "RADIAL";
3.1.4.3. on bias-belted tyres, the Letter "B" placed in front of the rim-diameter marking, and in
addition the words "BIAS-BELTED";
3.1.4.4. on radial-ply tyres suitable for speeds in excess of 240km/h but not exceeding 300km/h
(tyres marked with the speed symbol “W” or “Y” as part of the service description), the
Letter "R", placed before the rim diameter code marking, may be replaced with the
inscription "ZR".
3.1.4.5. on "run-flat" or "self-supporting" tyres the Letter "F" placed in front of the rim diameter
marking.
3.1.5. An indication of the tyre's speed category symbol.
3.1.5.1. On tyres suitable for speeds in excess of 300km/h, the Letter "R" placed in front of the rim
diameter code marking shall be replaced by the inscription "ZR" and the tyre shall be
marked with a service description consisting of the speed symbol ‘Y’ and the corresponding
load index.. The service description shall be marked within brackets e.g.: '(95Y)'.
3.1.6. The inscription M+S or M.S. or M&S if the tyre is classified in the category of use "snow
tyre";

3.4. The markings referred to in Paragraph 3.1. and the approval mark prescribed in
Paragraph 5.4. of this Regulation shall be moulded on to or into the tyres. They shall be
clearly legible and situated in the lower area of the tyre on at least one of its side walls,
except for the inscription mentioned in Paragraph 3.1.1. and 3.1.12. above.
3.4.1. However, for tyres identified by the "tyre to rim fitment configuration"
(see Paragraph 3.1.10.), Symbol "A" or "U", the markings may be placed anywhere on the
outside sidewall of the tyre.
4. APPLICATION FOR APPROVAL
4.1. The application for approval of a type of tyre with regard to this Regulation shall be
submitted by the tyre manufacturer or by his duly accredited representative. It shall specify:
4.1.1. The tyre-size designation;
4.1.2. The manufacturer's name;
4.1.2.1. The Brand name(s)/trademark(s);
4.1.2.2. The trade description(s)/commercial name(s).
4.1.3. The category of use normal tyre or snow-tyre, or special use tyre, or for temporary use;
4.1.4. Structure: diagonal (bias ply), bias belted, radial, run flat tyre;
4.1.5. The speed category;
4.1.6. The load-capacity index of the tyre;
4.1.7. Whether the tyre is to be used with or without an inner tube;
4.1.8. Whether the tyre is "standard" or "reinforced" or "T-type temporary use spare tyre";
4.1.9. The ply-rating number of diagonal (bias-ply) tyres;
4.1.10. The overall dimensions: overall section width and outer diameter;
4.1.11. The rims on which the tyre can be mounted;
4.1.12. The measuring rim and test rim;
4.1.13. The test pressure where the manufacture requests the application of Annex 7,
Paragraph 1.3. to this Regulation;
4.1.14. The factor x referred to in Paragraph 2.22. above.
4.1.15. For tyres suitable for speeds in excess of 300km/h, the maximum speed permitted by the
tyre manufacturer and the load carrying capacity allowed for that maximum speed. The tyre
manufacturer must also specify these values in the technical literature for the tyre type.
4.1.16. The identification of the bead retention rim contours specific for the "flat tyre running mode"
of "run flat tyres".

5.4. There shall be affixed conspicuously to every tyre conforming to a type of tyre approved
under this Regulation, in the space referred to in Paragraph 3.2. above and in addition to the
markings prescribed in Paragraph 3.1. above, an international approval mark consisting of:
5.4.1. A circle surrounding the Letter "E" followed by the distinguishing number of the country
which has granted approval; and
5.4.2. An approval number.
5.5. The approval mark shall be clearly legible and be indelible.
5.6. Annex 2 to this Regulation gives an example of the arrangement of the approval mark.
6. REQUIREMENTS
6.1. Dimensions of tyres
6.1.1. Section Width of a Tyre
6.1.1.1. The section width shall be calculated by the following formula:
where
S =S + K(A − A ),
S
S
A
A
A
is the "section width" rounded to the nearest mm and measured on the measuring
rim;
is the "nominal section width" (in mm) as shown on the side wall of the tyre in the
designation of the tyre as prescribed;
is the width (expressed in mm) of the measuring rim, as shown by the manufacturer in
the descriptive note;
is the width (expressed in mm) of the theoretical rim.
shall be taken to equal S multiplied by the factor x, as specified by the manufacturer,
and K shall be taken to equal 0.4.

6.1.4.2.3. in addition, if the tyre has special protective ribs (or bands), the figures as increased by the
above tolerance may be exceeded by 8mm.
6.1.4.2.4. However, for tyres identified by the "tyre to rim fitment configuration"
(see Paragraph 3.1.10.) Symbol "A" or "U", the overall width of the tyre, in the lower area of
the tyre, equals the nominal width of the rim on which the tyre is mounted, as shown by the
manufacturer in the descriptive note, increased by 20mm.
6.1.5. Tyre Outer Diameter Specifications
The outer-diameter of a tyre must not be outside the values D
and D
obtained from the
following formulae:
D = d + 2 × H
D = d + 2 × H
where:
H = H × a rounded to the nearest mm
H = H × b rounded to the nearest mm
and
6.1.5.1. For sizes listed in Annex 5, and for tyres identified by the "tyre to rim fitment configuration"
(see Paragraph 3.1.11.) Symbol "A" or "U", the nominal section height H is equal to:
H = 0.5 (D - d) rounded to the nearest mm – for references see Paragraph 6.1.2.1.,
6.1.5.2. for other sizes, not listed in Annex 5, "H" and "d" are as defined in Paragraph 6.1.2.1.,
6.1.5.3. Coefficients "a" and "b" are respectively:
6.1.5.3.1. Coefficient "a" = 0.97
6.1.5.3.2.
Coefficient "b"
Radial, Run flat tyre
Diagonal and Bias Belted
for normal tyres
1.04
1.08
for special-use tyres
1.06
1.09
6.1.5.4. For snow tyres the overall diameter shall not exceed the following value
D = 1.01 × D rounded to the nearest mm
where D is the maximum outer diameter established in conformity with the above.

6.3.2. In order to be classified as a "professional off-road tyre", a tyre shall have all of the following
characteristics:
(a)
(b)
(c)
A tread depth ≥11mm;
A void-to-fill ratio ≥35%;
A maximum speed rating of ≤Q.
6.3.3. Tread-wear Indicators
6.3.3.1. The tyre shall include not less than six transverse rows of wear indicators, approximately
equally spaced and situated in the principal grooves of the tread. The tread-wear indicators
shall be such that they cannot be confused with the rubber ridges between the ribs or blocks
of the tread.
6.3.3.2. However, in the case of tyres of dimensions appropriate for mounting on rims of a nominal
diameter of 12 or less, four rows of tread-wear indicators shall be accepted.
6.3.3.3. The tread-wear indicators must provide a means of indicating, with a tolerance of
+ 0.60/− 0.00mm, when the tread grooves are no longer more than 1.6mm deep.
6.3.3.4. The height of tread-wear indicators is determined by measuring the difference between the
depth, from the tread's surface, to the top of the tread-wear indicator and to the bottom of
the tread groove close to the slope at the base of the tread-wear indicator.
7. MODIFICATIONS OF THE TYPE OF TYRE AND EXTENSION OF APPROVAL
7.1. Every modification of the type of tyre shall be notified to the administrative department which
approved the type of tyre. The department may then either:
7.1.1. Consider that the modifications made are unlikely to have an appreciable adverse effect and
that in any case, the tyre still complies with the requirements; or
7.1.2. Require a further test report from the technical service responsible for conducting the tests.
7.2. A modification of the tread pattern of the tyre shall not be considered to necessitate a
repetition of the tests prescribed in Paragraph 6 of this Regulation.
7.3. Confirmation or refusal of approval, specifying the alterations, shall be communicated by the
procedure specified in Paragraph 5.3. above to the Parties to the Agreement which apply
this Regulation.
7.4. The competent authority issuing the extension of approval shall assign a series number for
such an extension and inform thereof the other Parties to the 1958 Agreement applying this
Regulation by means of a communication form conforming to the model in Annex 1 to this
Regulation.

12. NAMES AND ADDRESSES OF TECHNICAL SERVICES RESPONSIBLE FOR
CONDUCTING APPROVAL TESTS AND OF TYPE APPROVAL AUTHORITIES
12.1. The Contracting Parties to the 1958 Agreement which apply this Regulation shall
communicate to the United Nations Secretariat the names and addresses of the technical
services responsible for conducting approval tests and, where applicable, of the Type
Approval Authorities which grant approval and to which forms certifying approval, or
extension of approval, or refusal of approval or withdrawal of approval or production
definitively discontinued, issued in other countries, are to be sent.
12.2. The Contracting Parties to the 1958 Agreement which apply this Regulation may designate
laboratories of tyre manufacturers as approved, test laboratories.
12.3. Where a Contracting Party to the 1958 Agreement applies Paragraph 12.2. above, it may, if
it so desires, be represented at the tests by one or more persons of its choice.
Explanatory figure
(See Paragraph 2. of the Regulation)

5. Technical service and, where applicable, test laboratory approved for purposes of approval or
of verification of conformity .............................................................................................................
6. Date of report issued by that service: .............................................................................................
7. Number of report issued by that service: ........................................................................................
8. Reason(s) of extension (if applicable): ............................................................................................
9. Any remarks: ...................................................................................................................................
10. Place ...............................................................................................................................................
11. Date .................................................................................................................................................
12. Signature .........................................................................................................................................
13. Annexed to this communication is a list of documents in the approval file deposited at the
Administrative services having delivered the approval and which can be obtained upon request.

ANNEX 3
ARRANGEMENT OF TYRE MARKINGS
1. Example of the markings to be borne by type of tyres placed on the market after the entry into
force of this regulation
b = 6mm (min.)
c = 4mm (min.)
These markings define a tyre:
(a) having a nominal section width of 185;
(b) having a nominal aspect ratio of 70;
(c)
of radial-ply structure (R);
(d) having a nominal rim diameter of 14;
(e)
(f)
(g)
(h)
having a load capacity of 580 kg, corresponding to load index 89 in Annex 4 to this
Regulation;
of speed category T (maximum speed 190km/h);
for fitting without an inner tube ("tubeless");
of "snow" type (M+S);
(i) manufactured during the twenty-fifth week of the year 2003.

ANNEX 4
LOAD-CAPACITY INDICES
Li = Load-capacity index
kg = Corresponding mass of the vehicle which is to be carried
Li kg Li kg Li kg Li kg

Table II. Millimetric Series - Radial (European Tyres)
Size
Measuring rim
width code
Overall
diameter mm
Tyre section
width mm
Nominal rim
diameter d' (mm)
125 R 10
145 R 10
3.5
4
459
492
127
147
254
254
125 R 12
135 R 12
145 R 12
155 R 12
3.5
4
4
4.5
510
522
542
550
127
137
147
157
305
305
305
305
125 R 13
135 R 13
145 R 13
155 R 13
165 R 13
175 R 13
185 R 13
3.5
4
4
4.5
4.5
5
5.5
536
548
566
578
596
608
624
127
137
147
157
167
178
188
330
330
330
330
330
330
330
125 R 14
135 R 14
145 R 14
155 R 14
165 R 14
175 R 14
185 R 14
195 R 14
205 R 14
215 R 14
225 R 14
3.5
4
4
4.5
4.5
5
5.5
5.5
6
6
6.5
562
574
590
604
622
634
650
666
686
700
714
127
137
147
157
167
178
188
198
208
218
228
356
356
356
356
356
356
356
356
356
356
356
125 R 15
135 R 15
145 R 15
155 R 15
165 R 15
175 R 15
185 R 15
195 R 15
205 R 15
215 R 15
225 R 15
235 R 15
3.5
4
4
4.5
4.5
5
5.5
5.5
6
6
6.5
6.5
588
600
616
630
646
660
674
690
710
724
738
752
127
137
147
157
167
178
188
198
208
218
228
238
381
381
381
381
381
381
381
381
381
381
381
381
175 R 16
185 R 16
205 R 16
5
5.5
6
686
698
736
178
188
208
406
406
406

ANNEX 6
METHOD OF MEASURING TYRES
1.1. Mount the tyre on the measuring rim specified by the manufacturer pursuant to
Paragraph 4.1.12. of this Regulation and inflate it to a pressure of 3 to 3.5 bar.
1.2. Adjust the pressure as follows:
1.2.1. in standard bias-belted tyres: to 1.7 bar;
1.2.2. in diagonal (bias-ply) tyres: to:
Pressure (bar)
Ply Rating
Speed Category
L, M, N P, Q, R, S T, U, H, V
4
6
8
1.7
2.1
2.5
2.0
2.4
2.8

2.6
3.0
1.2.3. in standard radial tyres: to 1.8 bar;
1.2.4. in reinforced tyres: to 2.2 bar;
1.2.5. in T-tyre temporary use spare tyres: to 4.2. bar.
2. Condition the tyre, mounted on its rim, at the ambient room temperature for not less than
24 hours, save as otherwise prescribed in Paragraph 6.2.3. of this Regulation.
3. Readjust the pressure to the level specified in Paragraph 1.2. above.
4. Measure the overall width by calliper at six equally-spaced points, taking the thickness of
the protective ribs or bands into account. The highest measurement so obtained is taken as
the overall width.
5. Determine the outer diameter by measuring the maximum circumference and dividing the
figure so obtained by π (3.1416).

2.2.3. the maximum load rating associated with a maximum speed of 270km/h for tyres with
Speed Symbol "W" (see Paragraph 2.34.3. of this Regulation).
2.2.4. the maximum load rating associated with a maximum speed of 300km/h for tyres with
Speed Symbol "Y" (see Paragraph 2.34.4. of this Regulation).
2.3. Throughout the test the tyre pressure must not be corrected and the test load must be kept
constant.
2.4. During the test the temperature in the test-room must be maintained at between 20° and 30°
or at a higher temperature if the manufacturer agrees.
2.5. Carry the test through, without interruption in conformity with the following particulars:
2.5.1. time taken to pass from zero speed to initial test speed: 10min;
2.5.2. initial test speed: prescribed maximum speed for the type of tyre (see Paragraph. 2.31.1 of
this Regulation), less 40km/h in the case of the smooth wheel having 1.70m ± 1% in
diameter or less 30km/h in the case of the smooth wheel having 2m ± 1% in diameter;
2.5.3. successive speed increments: 10km/h;
2.5.4. duration of test at each speed step except the last: 10min;
2.5.5. duration of test at last speed step: 20min;
2.5.6. maximum test speed: prescribed maximum speed for the type of tyre, less 10km/h in the
case of the smooth wheel having 1.7m ± 1% in diameter or equal to the prescribed
maximum speed in the case of the smooth wheel having 2m ± 1% in diameter.
2.5.7. however, for tyres suitable for maximum speed of 300km/h (Speed Symbol "Y"), the
duration of the test is 20min at the initial test speed step and 10min at the last speed step.
2.6. The procedure for the second test (see Paragraph 6.2.1.1.), to assess the performance of a
tyre suitable for speeds in excess of 300km/h, shall be as follows:
2.6.1. Apply to the test axle a load equal to 80% of the maximum load rating associated with the
maximum speed specified by the tyre manufacturer (see Paragraph 4.1.15. of this
Regulation).
2.6.2. The test shall be run without interruptions in accordance with the following:
2.6.2.1. 10min to build up from zero to the maximum test speed for the second test.
2.6.2.2. 5min at the maximum test speed for the second test.
2.6.2.3. maximum test speed for the second test: maximum speed specified by the tyre
manufacturer (see Paragraph 4.1.15. of this Regulation), less 10km/h in the case of the
smooth wheel having 1.7m ± 1% in diameter or equal to the maximum speed specified by
the tyre manufacturer in the case of the smooth wheel having 2m ± 1% in diameter.

Tyres.