ASTM D4821-03a

Standard Guide for Carbon Black—Validation of Test Method Precision and Bias

SCOPE
1.1 This guide covers a procedure for using ASTM Standard Reference Blacks (SRBs) to continuously monitor the precision of those carbon black test methods for which standard values have been established. It also offers guidelines for troubleshooting various test methods.
1.2 This guide establishes the x-chart control limits to be used when continuously monitoring those tests listed in Section 2. Alternatively, these control limits may be used as a basis for comparison to testing precision computed within a laboratory.
1.3 This guide uses statistical control chart methodology as discussed in STP-15-D to determine if a laboratory's test results differ significantly from the accepted values of the SRBs.
1.4 This guide provides a statistical procedure for improving test reproducibility when a laboratory cannot physically calibrate its apparatus to obtain the standard values of the ASTM SRBs, within the ranges given in the precision statement of the test method.
1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.6 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.

General Information

• Status: Historical
• Publication Date: 30-Nov-2003
• ICS: 83.040.20 - Rubber compounding ingredients
• Technical Committee: D24 - Carbon Black
• Drafting Committee: D24.61 - Carbon Black Sampling and Statistical Analysis

Relations

• Replaces: ASTM D4821-03 - Standard Guide for Carbon Black—Validation of Test Method Precision and Bias
• Effective Date: 01-Dec-2003
• Replaced By: ASTM D4821-04 - Standard Guide for Carbon Black—Validation of Test Method Precision and Bias
• Effective Date: 01-Jun-2004
• Referred By: ASTM D8466-22 - Standard Guide for Recovered Carbon Black—Carbon Black Test Methods for Testing rCB
• Effective Date: 01-Dec-2003
• Referred By: ASTM D1510-23 - Standard Test Method for Carbon Black—Iodine Adsorption Number
• Effective Date: 01-Dec-2003
• Referred By: ASTM D8043-20 - Standard Guide for Carbon Black—Shelf Life
• Effective Date: 01-Dec-2003
• Referred By: ASTM D6915-23 - Standard Practice for Carbon Black—Evaluation of Standard Reference Blacks
• Effective Date: 01-Dec-2003
• Referred By: ASTM D3265-23 - Standard Test Method for Carbon Black—Tint Strength
• Effective Date: 01-Dec-2003
• Referred By: ASTM D2414-23 - Standard Test Method for Carbon Black—Oil Absorption Number (OAN)
• Effective Date: 01-Dec-2003
• Referred By: ASTM D3493-21 - Standard Test Method for Carbon Black—Oil Absorption Number of Compressed Sample (COAN)
• Effective Date: 01-Dec-2003

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D 4821 – 03a
Standard Guide for
Carbon Black—Validation of Test Method Precision and
1
Bias
This standard is issued under the fixed designation D 4821; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope D 1510 Test Method for Carbon Black—Iodine Adsorption
Number
1.1 This guide covers a procedure for using ASTM Standard
2
D 1765 Classification System for Carbon Blacks Used in
Reference Blacks (SRBs) to continuously monitor the preci-
Rubber Products
sion of those carbon black test methods for which standard
D 2414 Test Method for Carbon Black—Oil Absorption
values have been established. It also offers guidelines for
Number
troubleshooting various test methods.
D 3265 Test Method for Carbon Black—Tint Strength
1.2 This guide establishes the x-chart control limits to be
D 3493 Test Method for Carbon Black—Oil Absorption
used when continuously monitoring those tests listed in Section
Number of Compressed Sample
2. Alternatively, these control limits may be used as a basis for
D 6556 Test Methods for Carbon Black—Total and Exter-
comparison to testing precision computed within a laboratory.
nal Surface Area by Nitrogen Adsorption
1.3 This guide uses statistical control chart methodology as
3
discussed in STP-15-D to determine if a laboratory’s test
3. Significance and Use
results differ significantly from the accepted values of the
3.1 One of the major causes of poor test precision is the lack
SRBs.
of calibration or standardization of instruments, apparatus,
1.4 This guide provides a statistical procedure for improv-
reagents, and technique among laboratories. The sum of all
ing test reproducibility when a laboratory cannot physically
sources of testing error is unique for an individual laboratory.
calibrate its apparatus to obtain the standard values of the
A least-squares regression of a laboratory’s actual test values
ASTM SRBs, within the ranges given in the precision state-
for reference materials to the established mean values will
ment of the test method.
result in a unique least-squares regression line (and equation)
1.5 The values stated in SI units are to be regarded as the
for that laboratory. Generally, there are two reasons for using
standard. The values given in parentheses are for information
the SRBs in testing: (1) to monitor testing performance (see
only.
Section 4) to ensure that no systematic error or bias is affecting
1.6 This standard does not purport to address all of the
the test results, or (2) to establish a statistical calibration (see
safety concerns, if any, associated with its use. It is the
Section 5) when the correction of assignable causes (see
responsibility of the user of this standard to establish appro-
Section 6) does not yield in-control test results.
priate safety and health practices and determine the applica-
3.2 In addition to the calibration of a test method by
bility of regulatory limitations prior to use.
physicochemical means, a statistical method for achieving
2. Referenced Documents calibration of a test method is presented.
4 3.3 This guide outlines the use of control charts to graphi-
2.1 ASTM Standards:
cally present calibration test data determined for the ASTM
SRBs for those test methods given in Section 2. All laborato-
1
This guide is under the jurisdiction of ASTM Committee D24 on Carbon Black
ries are encouraged to utilize statistical control charts and the
and is the direct responsibility of Subcommittee D24.61 on Carbon Black Sampling
SRBs because this allows a comparison of testing precision
and Statistical Analysis.
within a laboratory to the “industry average” values found in
Current edition approved Dec. 1, 2003. Published January 2004. Originally
Table 1.
approved in 1988. Last previous edition approved in 2003 as D 4821 – 03.
2
Standard Reference Blacks are available from Laboratory Standards & Tech-
3.4 The techniques of this guide can be used to continuously
nologies, Inc., 227 Somerset St., Borger, TX 79007. Phone/fax: [phone].
monitor testing execution and precision for other tests that are
E-mail: jwbal@infinitytx.net.
3
not listed in Section 2 or for materials that fall outside the range
Symposium on Manual on Presentation of Data and Control Chart Analysis,
ASTM STP 15D, ASTM, 1976. of the SRBs for those tests listed in Section 2. In these cases,
4
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
each laboratory will have to establish the applicable mean and
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
control limit values for the “local reference.” The mo
...