ASTM F1806-97(2008)
(Practice)Standard Practice for Tire Testing Operations-Basic Concepts and Terminology for Reference Tire Use
Standard Practice for Tire Testing Operations-Basic Concepts and Terminology for Reference Tire Use
SCOPE
1. Scope
1.1 This practice presents some basic concepts for tire testing and a standard set of terms relating to the use of reference tires frequently used for comprehensive tire testing programs. The tests may be conducted in a laboratory on various dynamometer wheels or other apparatus as well as at outdoor proving ground facilities. The overall objective of this practice is to develop some elementary principles for such testing and standardize the terms used in these operations. This will improve communication among those conducting these tests as well as those using the results of such testing.
1.2 In addition to the basic concepts and terminology, a statistical model for tire testing operations is also presented in . This serves as a mathematical and conceptual foundation for the terms and other testing concepts; it will improve understanding. The annex can also serve for future consultation as this practice is expanded to address additional aspects of the testing process.
1.3 This overall topic requires a comprehensive treatment with a sequential or hierarchical development of terms with substantial background discussion. This cannot be accommodated in Terminology F 538.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
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Designation: F1806 − 97(Reapproved 2008)
Standard Practice for
Tire Testing Operations–Basic Concepts and Terminology
for Reference Tire Use
This standard is issued under the fixed designation F1806; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope F538Terminology Relating to the Characteristics and Per-
formance of Tires
1.1 This practice presents some basic concepts for tire
F1082Practice for Tires—Determining Precision for Test
testing and a standard set of terms relating to the use of
Method Standards (Withdrawn 2005)
reference tires frequently used for comprehensive tire testing
F1650Practice for Evaluating Tire Traction Performance
programs. The tests may be conducted in a laboratory on
Data Under Varying Test Conditions
various dynamometer wheels or other apparatus as well as at
outdoor proving ground facilities.The overall objective of this
3. Significance and Use
practice is to develop some elementary principles for such
3.1 Tire testing operations usually consist of a sequence of
testingandstandardizethetermsusedintheseoperations.This
tests that involve special “reference” tires in addition to the
will improve communication among those conducting these
candidate tires being evaluated for their performance charac-
tests as well as those using the results of such testing.
teristics. Reference tires serve as an “internal benchmark”
1.2 In addition to the basic concepts and terminology, a
which may be used to adjust for variation in test results to give
statistical model for tire testing operations is also presented in
improved comparisons among the candidate tires. Numerous
Annex A1. This serves as a mathematical and conceptual
approaches have been adopted using different terminology for
foundation for the terms and other testing concepts; it will
such testing. This causes confusion and the purpose of this
improve understanding. The annex can also serve for future
practice is to standardize some of the elementary concepts and
consultation as this practice is expanded to address additional
terminology on this topic.
aspects of the testing process.
4. Summary of the Practice
1.3 This overall topic requires a comprehensive treatment
with a sequential or hierarchical development of terms with
4.1 Elementary testing concepts, terms, and definitions are
substantial background discussion. This cannot be accommo-
developed in hierarchical or sequential order beginning with
dated in Terminology F538.
basic testing operations. Each definition may be accompanied
1.4 This standard does not purport to address all of the byaspecificdiscussionorexpandedtextsectionappropriateto
safety concerns, if any, associated with its use. It is the general definitions. Many of the terms could be defined as
responsibility of the user of this standard to establish appro- adjectives; however, as recommended by ASTM policy, the
priate safety and health practices and determine the applica- word “tire” is included in each definition avoiding the compli-
bility of regulatory limitations prior to use. cation of defining adjectives. The definitions apply equally to
items or objects other than tires.
2. Referenced Documents
5. Basic Testing Concepts and Terms
2.1 ASTM Standards:
5.1 Background on Testing:
E1136Specification for P195/75R14 Radial Standard Refer-
5.1.1 Despite the adoption of standardized testing
ence Test Tire
procedures, test result variation influences data generated in
any type of testing. As outlined in Annex A1, there are two
1 main categories: [1] variation inherent in the production
This practice is under the jurisdiction of Committee F09 on Tires and is the
direct responsibility of Subcommittee F09.94 on Terminology. process for a group of nominally identical objects or tires and
Current edition approved May 1, 2008. Published June 2008. Originally
[2] variation due to the measurement operation. Each of these
´1
approved in 1997. Last previous edition approved in 2001 as F1806–97 (2001) .
twosourcesmaybefurtherdividedintotwotypesofvariation;
DOI: 10.1520/F1806-97R08.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on The last approved version of this historical standard is referenced on
the ASTM website. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1806 − 97(Reapproved 2008)
[1]
F1806 − 97 (2008)
systematic or bias variation (the variation causing one labora- 5.4 sample, n—a selected number of n test objects that
tory to be consistently different from another laboratory) and accurately represent the lot or population of interest.
[2]randomerrorvariation.Bothtypescanexistsimultaneously 5.4.1 Discussion—Alotisafinitenumberofobjectssuchas
for either of the main categories. a limited period of tire production at a given facility or a
selected number of tires of a particular commercial market
5.1.2 Random variation can be reduced to a low level by
appropriate replication and sampling procedures, but bias type.Apopulation is the collection (or potential collection) of
all objects produced by a given process or operation.
variation cannot be so reduced. Bias variation can be reduced
or eliminated by the appropriate use of reference objects or
5.5 sampling, v—the act of selecting samples.
tires. This is the major rationale for their use in testing
5.5.1 Discussion—The primary purpose of sampling is the
operations (see Annex A1).
reduction of random production process variation. See Annex
5.1.3 Bias variation can also be reduced or eliminated by
A1 for details.
comprehensive programs to sort out causes of such perturba-
5.6 replicate, n—either (1) an individual test object from a
tions and eliminate these causes.
sample of n objects or (2) one of m individual test values for a
5.2 Elementary Testing Terms:
test object.
5.2.1 test (or testing), n—a procedure performed on an
5.6.1 Discussion—Each test object of a set of replicates is
object (or set of nominally identical objects) using specified
nominally identical to all other objects from that particular
equipment that produces data unique to the object (or set).
source. Nominally identical implies that in long run testing all
5.2.1.1 Discussion—Test data are used to evaluate or model
objects would give essentially identical average test values.
selected properties or characteristics of the object (or set of
5.7 replication, v—the act of selecting and testing a number
objects). The scope of testing depends on the decisions to be
of replicates.
madeforanyprogram,andsamplingandreplicationplans(see
5.7.1 Discussion—The primary purpose of replication is the
definitions below) need to be specified for a complete program
reduction of random measurement variation. See Annex A1
description.
(A1.3.6) for additional discussion on types of replication.
5.2.2 test tire, n—a tire used in a test.
5.2.3 test program, n—an ordered series of tests grouped
6. Reference Tire Concepts and Terms
together using a predefined plan.
6.1 In this section a basic term, reference tire, is defined.A
5.2.3.1 Discussion—A test program may include multiple
number of terms, each describing a special type of reference
test repetitions over an extended time period.
tire, are derived from the basic term. Reference tires usually
5.2.4 testtireset,n—oneormoretesttiresasrequiredbythe
havespecialcharacteristicsuniquetoaparticulartestprogram.
test equipment or procedure, to perform a test, thereby produc-
However, for some testing programs the same reference tire
ing a single test result.
may be used for more than one purpose.
5.2.4.1 Discussion—The four nominally identical tires re-
6.1.1 reference tire, n—a special tire included in a test
quiredforvehiclestoppingdistancetestingconstituteatesttire
program;thetestresultsforthistirehavesignificanceasabase
set. In the discussion below where the test tire is mentioned, it
value or internal benchmark.
is assumed that test tire set may be substituted for test tire, if a
6.1.2 There are two types of reference tires or objects that
test tire set is required for the testing.
may be used in any test program.
5.2.5 candidate tire, n—a test tire that is part of a test
6.1.2.1 Type 1 (reference tire), n—tires subject to produc-
program.
tion, composition, and often, performance specifications; they
5.2.5.1 Discussion—The term “candidate object” may be
aredesignedtohaveminimalvariationandtobestableintheir
used in the same sense as candidate tire.
characteristic properties for an extended period of time.
5.2.6 candidate tire set—a set of candidate tires.
6.1.2.2 Type 2 (reference tire), n—tires appropriately se-
5.3 Tire testing may be divided into two major categories:
lected from a lot by a process that ensures minimal variation
5.3.1 localtesting,n—testingconductedatonelaboratoryor
characteristic properties for the duration of any test program.
test site for the purpose of comparing a number of candidate
6.1.3 Discussion—Type2referencetiresmaybeselectedon
tires for selected characteristic properties.
anadhocbasisandwhenthetestprogramiscompletetheyare
5.3.1.1 Discussion—Atire manufacturer’s internal develop-
no longer considered as reference objects.
ment programs and proving ground testing conducted by a 6.1.4 control tire, n—a reference tire used in a specified
contract testing organization to compare commercial market
manner throughout a test program.
tires are two examples of local testing.
6.1.4.1 Discussion—Acontroltiremaybeofeithertypeand
5.3.2 global testing, n—testing conducted at two or more typical tire use is the reference (control) tire in Practice F1650
laboratoriesortestsitesforthepurposeofcomparingcandidate
that provides algorithms for correcting (adjusting) test data for
tire performance at each location for selected characteristic bias trend variations (See Practice F1650 and Annex A1).
properties.
6.1.5 surface monitoring tire, n—a reference tire used to
evaluate changes in a test surface over a selected time period.
5.3.2.1 Discussion—Producer-usertestingorinterlaboratory
comparisons for such properties as rolling resistance, endur- 6.1.6 standard reference test tire (SRTT), n—a tire that
ance, or high speed dynamometer wheel performance are meets the requirements of Specification E1136, commonly
examples of global testing. used as control tire or a surface monitoring tire.
F1806 − 97 (2008)
6.1.6.1 Discussion—This is a Type 1 reference tire. 7.3 Repeatability and Reproducibility:
6.1.7 witness tire, n—a reference tire with an extended
7.3.1 The terms repeatability and reproducibility are fre-
period of stability for specified characteristic properties.
quently used when discussing testing and the results of testing
6.1.7.1 Discussion—A Type 1 reference tire is typical for
programs. Some interpretations of these terms are different
this application.
than the standard definitions given in Practice F1082.
6.1.8 master set, n—a selected group of witness tires, each
7.3.1.1 repeatability, n—an established value, below which
different test response characteristics to provide a range of
the absolute difference between two “within-laboratory” or
values for the measured property or properties.
“within test site” test results may be expected to lie, with a
6.1.8.1 Discussion—A master set is frequently tested to
specified probability (Practice F1082).
determineifatestdeviceisfunctioninginanormalorintended
7.3.1.1.1 Discussion—Thetwotestresultsareobtainedwith
manner. If certain known or expected relationships are not
the same method on nominally identical test materials under
found among the witness tires constituting the set, remedial
the same conditions (same operator, apparatus, laboratory,
action is required for the testing equipment. Master sets are
location,andspecifiedtimeperiod),andintheabsenceofother
frequently used for global testing.
indications,thespecifiedprobabilityis0.95(thatis,95%).The
6.1.9 test matrix, n—a group of candidate tires usually
established value also may be called a “critical difference.”
specifiedreferencetires;alltestsarenormallyconductedinone
7.3.1.2 reproducibility, n—an established value, below
test program.
which the absolute difference between two “between-
6.1.9.1 Discussion—A test matrix may be used in either a
laboratory” or “between test site” test results may be expected
local or global test program. See also candidate tire set.
to lie, with a specified probability (Practice F1082).
6.1.10 calibrationtire,n—awitnesstiredesignedtoprovide
7.3.1.2.1 Discussion—Thetwotestresultsareobtainedwith
a fixed or known test value for selected properties.
the same method on nominally identical test materials under
6.1.10.1 Discussion—Calibration tire test results can be
differentconditions(differentlaboratories,locations,operators,
usedasstandardvaluestodetermineacceptabilityoflaboratory
apparatus,andinaspecifiedtimeperiod),andintheabsenceof
or test site performance. If a specified performance level is not
other indications, the specified probability is 0.95 (that is,
found, certain instrument adjustments may be made to com-
95%). The essential characteristic of reproducibility is the
pensate for unavoidable biases in interlaboratory or between-
variability of test results among typical laboratories or test
site programs.
sites.
7. Evaluating Testing Precision 7.3.2 Both repeatability and reproducibility are to some
degree generic in their definition.Additional information must
7.1 As indicated in Annex A1, there are two categories of
be supplied before the terms can be used without ambiguity.
variation: production process and measurement. Each of these
Themostimportantissueisthebetween–testresulttimeperiod
may in turn have two subclassifications: basis deviations and
orfrequency;itmustbespecified.Whatconstitutesatestresult
randomdeviations.Thepotentialeffectofallthesesourcescan
mustbedefined.BothoftheseareaddressedinPracticeF1082.
exert a profound influence on the variability of test data. The
Other details on testing are also needed. It is important to
presence of these sources is the rationale for using reference
emphasize two details about repeatability and reproducibility;
tires and for designing comprehensive testing programs with
(1) both are statistical parameters; defined as 2.83× S, where S
appropriate replication t
...
This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
e1
Designation:F1806–97 (Reapproved 2001) Designation:F 1806–97 (Reapproved
2008)
Standard Practice for
Tire Testing Operations–Basic Concepts and Terminology
for Reference Tire Use
This standard is issued under the fixed designation F 1806; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval. e NOTE—Editorial corrections were made
throughout the document in December 2001.
1. Scope
1.1 This practice presents some basic concepts for tire testing and a standard set of terms relating to the use of reference tires
frequently used for comprehensive tire testing programs. The tests may be conducted in a laboratory on various dynamometer
wheels or other apparatus as well as at outdoor proving ground facilities. The overall objective of this practice is to develop some
elementaryprinciples for such testing and standardizethetermsusedintheseoperations.Thiswillimprovecommunicationamong
those conducting these tests as well as those using the results of such testing.
1.2 In addition to the basic concepts and terminology, a statistical model for tire testing operations is also presented in Annex
A1. This serves as a mathematical and conceptual foundation for the terms and other testing concepts; it will improve
understanding. The annex can also serve for future consultation as this practice is expanded to address additional aspects of the
testing process.
1.3 This overall topic requires a comprehensive treatment with a sequential or hierarchical development of terms with
substantial background discussion. This cannot be accommodated in Terminology F 538.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2.1 ASTM Standards:
E1136Specification for a Radial Standard Reference Test Tire
F538Terminology Relating to the Characteristics and Performance of Tires
F1082Practice for Tires–Determining Precision for Test Method Standards
F1650Practice for Evaluating Tire Traction Performance Data Under Varying Test Conditions
E 1136 Specification for A Radial Standard Reference Test Tire
F 538 Terminology Relating to the Characteristics and Performance of Tires
F 1082 Practice for TiresDetermining Precision for Test Method Standards
F 1650 Practice for Evaluating Tire Traction Performance Data Under Varying Test Conditions
3. Significance and Use
3.1 Tiretestingoperationsusuallyconsistofasequenceofteststhatinvolvespecial“reference”tiresinadditiontothecandidate
tires being evaluated for their performance characteristics. Reference tires serve as an “internal benchmark” which may be used
to adjust for variation in test results to give improved comparisons among the candidate tires. Numerous approaches have been
adopted using different terminology for such testing. This causes confusion and the purpose of this practice is to standardize some
of the elementary concepts and terminology on this topic.
4. Summary of the Practice
4.1 Elementary testing concepts, terms, and definitions are developed in hierarchical or sequential order beginning with basic
testing operations. Each definition may be accompanied by a specific discussion or expanded text section appropriate to general
This practice is under the jurisdiction of Committee F09 on Tires and is the direct responsibility of Subcommittee F09.94 on Terminology.
Current edition approved May 10, 1997. Published April 1998.
´1
Current edition approved May 1, 2008. Published June 2008. Originally approved in 1997. Last previous edition approved in 2001 as F 1806 – 97 (2001) .
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
, Vol 04.03.volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
F 1806–97 (2008)
definitions. Many of the terms could be defined as adjectives; however, as recommended by ASTM policy, the word “tire” is
included in each definition avoiding the complication of defining adjectives.The definitions apply equally to items or objects other
than tires.
5. Basic Testing Concepts and Terms
5.1 Background on Testing:
5.1.1 Despite the adoption of standardized testing procedures, test result variation influences data generated in any type of
testing. As outlined in Annex A1, there are two main categories: [1] variation inherent in the production process for a group of
nominally identical objects or tires and [2] variation due to the measurement operation. Each of these two sources may be further
dividedintotwotypesofvariation;[1]systematicorbiasvariation(thevariationcausingonelaboratorytobeconsistentlydifferent
from another laboratory) and [2] random error variation. Both types can exist simultaneously for either of the main categories.
5.1.2 Random variation can be reduced to a low level by appropriate replication and sampling procedures, but bias variation
cannot be so reduced. Bias variation can be reduced or eliminated by the appropriate use of reference objects or tires. This is the
major rationale for their use in testing operations (see Annex A1).
5.1.3 Bias variation can also be reduced or eliminated by comprehensive programs to sort out causes of such perturbations and
eliminate these causes.
5.2 Elementary Testing Terms:
5.2.1 test (or testing), n—a procedure performed on an object (or set of nominally identical objects) using specified equipment
that produces data unique to the object (or set).
5.2.1.1 Discussion—Testdataareusedtoevaluateormodelselectedpropertiesorcharacteristicsoftheobject(orsetofobjects).
The scope of testing depends on the decisions to be made for any program, and sampling and replication plans (see definitions
below) need to be specified for a complete program description.
5.2.2 test tire, n— a tire used in a test.
5.2.3 test program, n— an ordered series of tests grouped together using a predefined plan.
5.2.3.1 Discussion—A test program may include multiple test repetitions over an extended time period.
5.2.4 test tire set, n— one or more test tires as required by the test equipment or procedure, to perform a test, thereby producing
a single test result.
5.2.4.1 Discussion—The four nominally identical tires required for vehicle stopping distance testing constitute a test tire set.
In the discussion below where the test tire is mentioned, it is assumed that test tire set may be substituted for test tire, if a test tire
set is required for the testing.
5.2.5 candidate tire, n—a test tire that is part of a test program.
5.2.5.1 Discussion—The term “candidate object” may be used in the same sense as candidate tire.
5.2.6 candidate tire set—a set of candidate tires.
5.3 Tire testing may be divided into two major categories:
5.3.1 local testing, n— testing conducted at one laboratory or test site for the purpose of comparing a number of candidate tires
for selected characteristic properties.
5.3.1.1 Discussion—Atire manufacturer’s internal development programs and proving ground testing conducted by a contract
testing organization to compare commercial market tires are two examples of local testing.
5.3.2 global testing, n—testing conducted at two or more laboratories or test sites for the purpose of comparing candidate tire
performance at each location for selected characteristic properties.
5.3.2.1 Discussion—Producer-user testing or interlaboratory comparisons for such properties as rolling resistance, endurance,
or high speed dynamometer wheel performance are examples of global testing.
5.4 sample, n—a selected number of n test objects that accurately represent the lot or population of interest.
5.4.1 Discussion—Alot is a finite number of objects such as a limited period of tire production at a given facility or a selected
number of tires of a particular commercial market type. A population is the collection (or potential collection) of all objects
produced by a given process or operation.
5.5 sampling, v— the act of selecting samples.
5.5.1 Discussion—The primary purpose of sampling is the reduction of random production process variation. SeeAnnexA1 for
details.
5.6 replicate, n— either (1) an individual test object from a sample of n objects or (2) one of m individual test values for a test
object.
5.6.1 Discussion—Each test object of a set of replicates is nominally identical to all other objects from that particular source.
Nominally identical implies that in long run testing all objects would give essentially identical average test values.
5.7 replication, v— the act of selecting and testing a number of replicates.
5.7.1 Discussion—The primary purpose of replication is the reduction of random measurement variation. See Annex A1
(A1.3.6) for additional discussion on types of replication.
6. Reference Tire Concepts and Terms
6.1 In this section a basic term, reference tire, is defined. A number of terms, each describing a special type of reference tire,
F 1806–97 (2008)
are derived from the basic term. Reference tires usually have special characteristics unique to a particular test program. However,
for some testing programs the same reference tire may be used for more than one purpose.
6.1.1 reference tire, n—a special tire included in a test program; the test results for this tire have significance as a base value
or internal benchmark.
6.1.2 There are two types of reference tires or objects that may be used in any test program.
6.1.2.1 Type 1 (reference tire), n —tires subject to production, composition, and often, performance specifications; they are
designed to have minimal variation and to be stable in their characteristic properties for an extended period of time.
6.1.2.2 Type 2 (reference tire), n —tires appropriately selected from a lot by a process that ensures minimal variation
characteristic properties for the duration of any test program.
6.1.3 Discussion—Type 2 reference tires may be selected on an ad hoc basis and when the test program is complete they are
no longer considered as reference objects.
6.1.4 control tire, n— a reference tire used in a specified manner throughout a test program.
6.1.4.1 Discussion—A control tire may be of either type and typical tire use is the reference (control) tire in Practice F 1650
that provides algorithms for correcting (adjusting) test data for bias trend variations (See Practice F 1650 and Annex A1).
6.1.5 surface monitoring tire, n —a reference tire used to evaluate changes in a test surface over a selected time period.
6.1.6 standard reference test tire (SRTT), n—a tire that meets the requirements of Specification E 1136, commonly used as
control tire or a surface monitoring tire.
6.1.6.1 Discussion—This is a Type 1 reference tire.
6.1.7 witness tire, n— a reference tire with an extended period of stability for specified characteristic properties.
6.1.7.1 Discussion—A Type 1 reference tire is typical for this application.
6.1.8 master set, n— a selected group of witness tires, each different test response characteristics to provide a range of values
for the measured property or properties.
6.1.8.1 Discussion—Amastersetisfrequentlytestedtodetermineifatestdeviceisfunctioninginanormalorintendedmanner.
If certain known or expected relationships are not found among the witness tires constituting the set, remedial action is required
for the testing equipment. Master sets are frequently used for global testing.
6.1.9 test matrix, n— a group of candidate tires usually specified reference tires; all tests are normally conducted in one test
program.
6.1.9.1 Discussion—A test matrix may be used in either a local or global test program. See also candidate tire set.
6.1.10 calibration tire, n—a witness tire designed to provide a fixed or known test value for selected properties.
6.1.10.1 Discussion—Calibration tire test results can be used as standard values to determine acceptability of laboratory or test
site performance. If a specified performance level is not found, certain instrument adjustments may be made to compensate for
unavoidable biases in interlaboratory or between-site programs.
7. Evaluating Testing Precision
7.1 As indicated in Annex A1, there are two categories of variation: production process and measurement. Each of these may
in turn have two subclassifications: basis deviations and random deviations. The potential effect of all these sources can exert a
profound influence on the variability of test data. The presence of these sources is the rationale for using reference tires and for
designing comprehensive testing programs with appropriate replication to reduce the effect of such variations.
7.2 Evaluating Precision—Special programs to evaluate the magnitude of variability for any routine or special test operations
are part of the effort to reduce variability and improve test precision. Precision is defined in Practice F 1082 as “a measurement
(testing) concept that expresses the ability to generate test results that agree with each other in absolute magnitude.” The
parenthetical word “testing” is added to this definition for this purposes of this practice to indicate that is is the overall testing
process, which includes sampling and replication, that should be considered when discussing precision.
7.2.1 For local testing, this action usually consists of appropriate sampling and replication plans and the evaluation of
“test-to-test” variation for candidate tires. With a “test-to-test” standard deviation (or variance) obtained under the appropriate
conditions, decisions on statistical (and technical) differences between candidate tires can be made for a program at any specific
location.Forglobaltesting,programscanbeorganizedtoevaluateanother“test-to-test”standarddeviation,wherethisnowapplies
to between-lab as well as to between-test comparisons.
7.3 Repeatability and Reproducibility :
7.3.1 Thetermsrepeatabilityandreproducibilityarefrequentlyusedwhendiscussingtestingandtheresultsoftestingprograms.
Some int
...
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