ASTM D6818-21

Standard Test Method for Tensile Properties of Rolled Erosion Control Products

SIGNIFICANCE AND USE
5.1 The strip test in this test method is considered satisfactory for acceptance testing (that is, conformance to a specification) of commercial shipments of rolled erosion control products, since the method has been used extensively in the trade for acceptance testing.  
5.1.1 In case of disagreement arising from differences in reported test values when using this test method for acceptance testing of commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. At a minimum, the two parties should take a group of test specimens which are as homogeneous as possible and are from a lot of material of the type in question. The test specimens should then be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using Student's t-test for unpaired data and an acceptable probability level chosen by the two parties before testing is begun. If bias is found, either its cause must be found and corrected, or the purchaser and the supplier must agree to interpret future results in the light of the known bias.
SCOPE
1.1 This test method covers strip test procedures for determining the tensile properties of rolled erosion control products (RECPs).  
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information purposes only.  
1.3 This standard does not apply to RECPs made of composite materials where the component providing the reinforcement cannot be tested for tensile strength with the procedure herein described. In this case, the established ASTM testing method which is most appropriate for that material shall be used instead.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 14-Feb-2021
• ICS: 83.120 - Reinforced plastics
• Technical Committee: D35 - Geosynthetics
• Drafting Committee: D35.05 - Geosynthetic Erosion Control

Relations

• Refers: ASTM D4439-24 - Standard Terminology for Geosynthetics
• Effective Date: 01-Feb-2024
• Refers: ASTM D4354-12(2020) - Standard Practice for Sampling of Geosynthetics and Rolled Erosion Control Products (RECPs) for Testing
• Effective Date: 01-May-2020
• Refers: ASTM D4439-18 - Standard Terminology for Geosynthetics
• Effective Date: 15-Apr-2018
• Refers: ASTM D4439-17 - Standard Terminology for Geosynthetics
• Effective Date: 01-Aug-2017
• Refers: ASTM D123-17 - Standard Terminology Relating to Textiles
• Effective Date: 01-Mar-2017
• Refers: ASTM D123-15b - Standard Terminology Relating to Textiles
• Effective Date: 15-Sep-2015
• Refers: ASTM D123-15a - Standard Terminology Relating to Textiles
• Effective Date: 01-Sep-2015
• Refers: ASTM D4439-15a - Standard Terminology for Geosynthetics
• Effective Date: 01-Sep-2015
• Refers: ASTM D4439-15 - Standard Terminology for Geosynthetics
• Effective Date: 01-Jul-2015
• Refers: ASTM D123-15 - Standard Terminology Relating to Textiles
• Effective Date: 01-Apr-2015
• Refers: ASTM E177-14 - Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods
• Effective Date: 01-May-2014
• Refers: ASTM D4439-14 - Standard Terminology for Geosynthetics
• Effective Date: 01-Mar-2014
• Refers: ASTM D123-13ae1 - Standard Terminology Relating to Textiles
• Effective Date: 15-Jun-2013
• Refers: ASTM D123-13a - Standard Terminology Relating to Textiles
• Effective Date: 15-Jun-2013
• Refers: ASTM D123-13 - Standard Terminology Relating to Textiles
• Effective Date: 15-May-2013

Overview

ASTM D6818-21: Standard Test Method for Tensile Properties of Rolled Erosion Control Products sets forth a widely recognized strip test procedure for determining the tensile properties of rolled erosion control products (RECPs). Developed by ASTM International, this standard outlines methods crucial for evaluating RECP performance, supporting quality assurance, specification conformance, and comparative product assessment in geotechnical and civil engineering applications. The method focuses primarily on non-composite RECPs, ensuring results are consistent, reproducible, and suitable for acceptance testing of commercial shipments.

Key Topics

• Scope and Applicability

  • Applies to rolled erosion control products (RECPs) not made from composite materials whose reinforcing components cannot be separately tested for tensile strength.
  • Sets SI units as the standard (with measurements in parentheses for reference only).
  • Requires users to independently ensure safety, health, and environmental compliance.

• Strip Test Methodology

  • Utilizes a strip test, where the full width of RECP specimens is gripped and subjected to tensile loading until rupture.
  • Results include values for breaking force (maximum applied force before specimen rupture) and elongation (percentage extension of specimen before failure).

• Sampling and Reporting

  • Details robust sampling procedures to ensure that the test specimens represent the bulk product and eliminate biases from outer layers or specimen distortion.
  • Specifies random assignment of specimens for interlaboratory comparisons if disputes arise between supplier and purchaser test results.
  • Recommends a minimum of five specimens when a reliable statistical estimate is not available.

• Measurement Precision

  • Defines procedures for ensuring repeatability within a single laboratory and reproducibility across laboratories.
  • Establishes use of accepted statistical methods, such as Student’s t-test, for data analysis and bias detection between different laboratories.
  • Recognizes no absolute bias due to the absence of reference materials, but provides guidance for comparative testing and data interpretation.

Applications

• Product Development and Quality Control

  • Manufacturers use ASTM D6818-21 to verify product consistency, tensile strength, and suitability for specific erosion control purposes before releasing products to market.
  • Enables standardization in product performance claims and facilitates specification compliance for procurement.

• Construction and Civil Engineering

  • Specifiers and contractors rely on the tensile property data obtained per this standard to select appropriate RECPs for use in soil stabilization, slope protection, channel lining, and other erosion-prone environments.
  • Test results aid in identifying the best-fit erosion control products for challenging site conditions and ensure that installed materials meet performance expectations.

• Procurement and Regulatory Compliance

  • Purchasers, regulatory agencies, and auditors reference ASTM D6818-21 to confirm product performance meets contract requirements and industry standards.
  • The method supports effective dispute resolution through prescribed interlaboratory comparison processes, fostering fair and reliable product acceptance.

Related Standards

• ASTM D76/D76M - Specification for Tensile Testing Machines for Textiles
• ASTM D123 - Terminology Relating to Textiles
• ASTM D4354 - Practice for Sampling of Geosynthetics and Rolled Erosion Control Products for Testing
• ASTM D4439 - Terminology for Geosynthetics
• ASTM E177 - Practice for Use of the Terms Precision and Bias in ASTM Test Methods
• ASTM E691 - Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method

Keywords: tensile properties, rolled erosion control products, ASTM D6818-21, RECPs, strip test, breaking force, elongation, geosynthetics, product acceptance, quality control

By adhering to ASTM D6818-21, stakeholders in the erosion control sector can ensure reliable, consistent, and comparable evaluation of the tensile properties of rolled erosion control products, supporting informed decision-making in specification, procurement, and field performance assessment.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D6818 − 21
Standard Test Method for
Tensile Properties of Rolled Erosion Control Products
This standard is issued under the fixed designation D6818; 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.
1. Scope E177 Practice for Use of the Terms Precision and Bias in
ASTM Test Methods
1.1 This test method covers strip test procedures for deter-
E691 Practice for Conducting an Interlaboratory Study to
mining the tensile properties of rolled erosion control products
Determine the Precision of a Test Method
(RECPs).
3. Terminology
1.2 The values stated in SI units are to be regarded as the
standard. The values given in parentheses are provided for
3.1 Definitions:
information purposes only.
3.1.1 constant rate of extension (CRE) tensile testing
1.3 This standard does not apply to RECPs made of com- machine—a testing machine in which the rate of increase of
specimen length is uniform with time.
posite materials where the component providing the reinforce-
ment cannot be tested for tensile strength with the procedure
3.1.2 elongation, n—the ratio of the extension of a material
herein described. In this case, the established ASTM testing
to the length of the material prior to stretching. (Compare
method which is most appropriate for that material shall be
extension.)
used instead.
3.1.3 extension, n—the change in length of a material due to
1.4 This standard does not purport to address all of the
stretching. (Compare elongation.)
safety concerns, if any, associated with its use. It is the
3.1.4 rupture, v—the act of bursting.
responsibility of the user of this standard to establish appro-
3.1.5 strip test, n—in RECP testing, a tensile test in which
priate safety, health, and environmental practices and deter-
the full width of the specimen is gripped in the clamps.
mine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accor- 3.2 For definitions of other terms used in this test method,
dance with internationally recognized principles on standard-
refer to Terminology D123 or Terminology D4439.
ization established in the Decision on Principles for the
4. Summary of Test Method
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
4.1 A test specimen is clamped in a tensile testing machine
Barriers to Trade (TBT) Committee.
and a force applied to the specimen until it breaks. Values for
the breaking force and elongation of the test specimen are
2. Referenced Documents
obtained from machine scales, dials, autographic recording
charts, or a computer interfaced with the testing machine.Also,
2.1 ASTM Standards:
points along the stress-strain curve can be reported.
D76/D76M Specification for Tensile Testing Machines for
Textiles
5. Significance and Use
D123 Terminology Relating to Textiles
5.1 The strip test in this test method is considered satisfac-
D4354 Practice for Sampling of Geosynthetics and Rolled
tory for acceptance testing (that is, conformance to a specifi-
Erosion Control Products (RECPs) for Testing
cation) of commercial shipments of rolled erosion control
D4439 Terminology for Geosynthetics
products, since the method has been used extensively in the
trade for acceptance testing.
This test method is under the jurisdiction of ASTM Committee D35 on
5.1.1 In case of disagreement arising from differences in
Geosynthetics and is the direct responsibility of Subcommittee D35.05 on Geosyn-
reported test values when using this test method for acceptance
thetic Erosion Control.
testing of commercial shipments, the purchaser and the sup-
Current edition approved Feb. 15, 2021. Published February 2021. Originally
plier should conduct comparative tests to determine if there is
approved in 2002. Last previous edition approved in 2018 as D6818 – 18a. DOI:
10.1520/D6818-21.
statistical bias between their laboratories. Competent statistical
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
assistance is recommended for the investigation of bias. At a
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
minimum, the two parties should take a group of test speci-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. mens which are as homogeneous as possible and are from a lot
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6818 − 21
of material of the type in question. The test specimens should obtained. Exclude the inner and outer layers or wraps of the
then be randomly assigned in equal numbers to each laboratory roll or any material containing folds, crushed areas, or other
for testing. The average results from the two laboratories distortions not representative of the sampled lot.
should be compared using Student’s t-test for unpaired data
7.3 Remove test specimens from the laboratory sample so
and an acceptable probability level chosen by the two parties
that each specimen will contain different machine and cross-
beforetestingisbegun.Ifbiasisfound,eitheritscausemustbe
machineelements,withnospecimentakennearerthan100mm
found and corrected, or the purchaser and the supplier must
(4 in.) from the roll sides or ends, unless otherwise specified.
agree to interpret future results in the light of the known bias.
7.4 Cut specimens with their long dimension parallel either
6. Apparatus
to the machine direction or to the cross-machine direction, or
cut specimens for testing both directions as required. Unless
6.1 Tensile Testing Machine, of the constant rate of exten-
otherwise specified, take specimens no nearer to the machine
sion (CRE) type conforming to Specification D76/D76M with
direction edge of the RECP than one tenth of the width of the
respect to force indication, working range, capacity, and
RECP. Cut each specimen 100 mm (4 in.) wide, by at least
elongation indicator and designed for operation at a speed of
150 mm (6 in.) long.
300 6 10 mm/min (12 6 0.5 in./min).
6.2 Clamps and Jaw Faces—Each jaw face shall be smooth,
NOTE 2—The length of the specimen depends on the type of clamps
being used.
flat, and with a metallic or other agreed-upon surface. The
NOTE 3—The specimens may be taped across the width on each side of
faces shall be parallel and have machining centers with respect
the long dimension to maintain specimen integrity during specimen
to one another in the same clamp and to the corresponding jaw
preparation and positioning within the clamps during setup and testing.
face of the other clamp. The jaw faces shall measure at least
Any tape with sufficient strength, adhesion, and durability to withstand
10 mm (0.5 in.) wider than the specimen being tested and at
grip pressures and hold specimen components securely is acceptable. The
least 25 mm (1.0 in.) in height. tape should not extend into the test area (that is, between the clamps,
within the 3-in. gage length). See Fig. 1.
6.3 Cutting Dies—The cutting dies must be capable of
7.4.1 If necessary, centrally, draw two lines running the full
cutting specimen dimensions 100 mm (4 in.) by at least
width of the specimen, accurately perpendicular to the length
150 mm (6 in.).
dimension and separated by 75 mm (3 in.) to designate the
NOTE 1—Due to possible loss of loose internal components during
gage area (see 9.2). For some woven RECPs, it may be
cutting and handling of many RECPs, care should be exercised to
necessary to cut each specimen 110 mm (4.5 in.) wide and then
minimize these effects.
remove an equal number of yarns from each side to obtain the
7. Sampling, Test Specimens, and Test Units
100-mm (4.0-in.) finished dimension. This helps maintain
specimen integrity during the test.
7.1 Lot Sample—In the absence of other guidelines, divide
the product into lots and take lot samples in accordance with
7.5 Number of Specimens—Unless otherwise agreed upon,
Practice D4354.
as when provided in an applicable material specification, take
the number of test specimens per laboratory sample as follows:
7.2 Laboratory Sample—For the laboratory sample, take a
full-width sample of sufficient length in the machine direction 7.5.1 Reliable Estimate of v—When there is a reliable
so that the required size and number of specimens can be estimate of v based upon extensive part records for similar
FIG. 1 Taping of Specimens
D6818 − 21
materials tested in the user’s laboratory as directed in this test 9.4 Readandrecordthebreakingforceandelongation,from
method, calculate the required number of specimens as follows the mechanism provided for such purpose. Record machine
so that the user may expect at the 95 % probability level that and cross-machine direction results separately. If desired,
the test result is not more than 5.0 % of the average above or additional points along the stress-strain curve can be recorded
below the average of the sample: as well.
n 5 tv ⁄ A (1)
~ !
9.5 For some machines, data may be obtained using an
interfaced computer.
where:
n = number of test specimens (rounded upward to a whole 9.6 If a specimen slips in the jaws, breaks at the edge of or
number), in the jaws, or if for any reason the result falls markedly below
v = coefficient of variation of individual observations on
the average of the set of specimens, it is not considered
similar materials in the user’s laboratory under condi- acceptable; discard the result and take another specimen.
tions of single-operator precision, %,
Continue this until the required number of breaks has been
t = value of Student’s t for one-sided limits, a 95 %
obtained.
probability level, and the degrees of freedom associated
9.7 Repeat 9.1 – 9.6 until the required number of breaks has
with the estimate of v (see Table 1), and
been obtained.
A = 5.0 % of the average, the value of the allowable
NOTE 4—It is difficult to determine the precise reason that certain
variation.
specimens break near
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM 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.
Designation: D6818 − 18a D6818 − 21
Standard Test Method for
Ultimate Tensile Properties of Rolled Erosion Control
Products
This standard is issued under the fixed designation D6818; 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.
1. Scope
1.1 This test method covers strip test procedures for determining the tensile properties of rolled erosion control products (RECPs).
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information
purposes only.
1.3 This standard does not apply to RECPs made of composite materials where the component providing the reinforcement cannot
be tested for tensile strength with the procedure herein described. In this case, the established ASTM testing method which is most
appropriate for that material shall be used instead.
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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D76/D76M Specification for Tensile Testing Machines for Textiles
D123 Terminology Relating to Textiles
D4354 Practice for Sampling of Geosynthetics and Rolled Erosion Control Products (RECPs) for Testing
D4439 Terminology for Geosynthetics
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions:
3.1.1 breaking load, n—the maximum force applied to a specimen in a tensile test carried to rupture.
This test method is under the jurisdiction of ASTM Committee D35 on Geosynthetics and is the direct responsibility of Subcommittee D35.05 on Geosynthetic Erosion
Control.
Current edition approved June 1, 2018Feb. 15, 2021. Published June 2018February 2021. Originally approved in 2002. Last previous edition approved in 2018 as D6818
– 18.18a. DOI: 10.1520/D6818-18A.10.1520/D6818-21.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
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
D6818 − 21
3.1.1.1 Discussion—
Materials that are brittle usually rupture at the maximum force. Materials that are ductile usually experience a maximum force
before rupturing.
3.1.1 constant rate of extension (CRE) tensile testing machine—a testing machine in which the rate of increase of specimen length
is uniform with time.
3.1.2 elongation, n—the ratio of the extension of a material to the length of the material prior to stretching. (Compare extension.)
3.1.3 extension, n—the change in length of a material due to stretching. (Compare elongation.)
3.1.4 rupture, v—the act of bursting.
3.1.5 strip test, n—in RECP testing, a tensile test in which the full width of the specimen is gripped in the clamps.
3.1.7 tensile test, n—in geosynthetics, a test in which a geosynthetic material is stretched in one direction to determine the
force-elongation characteristics, the breaking force, or the breaking elongation.
3.2 For definitions of other terms used in this test method, refer to Terminology D123 or Terminology D4439.
4. Summary of Test Method
4.1 A test specimen is clamped in a tensile testing machine and a force applied to the specimen until it breaks. Values for the
breaking force and elongation of the test specimen are obtained from machine scales, dials, autographic recording charts, or a
computer interfaced with the testing machine. Also, points along the stress-strain curve can be reported.
5. Significance and Use
5.1 The strip test in this test method is considered satisfactory for acceptance testing (that is, conformance to a specification) of
commercial shipments of rolled erosion control products, since the method has been used extensively in the trade for acceptance
testing.
5.1.1 In case of disagreement arising from differences in reported test values when using this test method for acceptance testing
of commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is statistical bias
between their laboratories. Competent statistical assistance is recommended for the investigation of bias. At a minimum, the two
parties should take a group of test specimens which are as homogeneous as possible and are from a lot of material of the type in
question. The test specimens should then be randomly assigned in equal numbers to each laboratory for testing. The average results
from the two laboratories should be compared using Student’s t-test for unpaired data and an acceptable probability level chosen
by the two parties before testing is begun. If bias is found, either its cause must be found and corrected, or the purchaser and the
supplier must agree to interpret future results in the light of the known bias.
6. Apparatus
6.1 Tensile Testing Machine, of the constant rate of extension (CRE) type conforming to Specification D76/D76M, with respect
to force indication, working range, capacity, and elongation indicator and designed for operation at a speed of 300 6 10 mm/min
(12 6 0.5 in./min).
6.2 Clamps and Jaw Faces—Each jaw face shall be smooth, flat, and with a metallic or other agreed-upon surface. The faces shall
be parallel and have machining centers with respect to one another in the same clamp and to the corresponding jaw face of the
other clamp. The jaw faces shall measure at least 10 mm (0.5 in.) wider than the specimen being tested and at least 25 mm (1.0
in.) in height.
6.3 Cutting Dies—The cutting dies must be capable of cutting specimen dimensions 100 mm (4 in.) by at least 150 mm (6 in.).
NOTE 1—Due to possible loss of loose internal components during cutting and handling of many RECPs, care should be exercised to minimize these
effects.
D6818 − 21
7. SamplingSampling, Test Specimens, and Test Units
7.1 Lot Sample—In the absence of other guidelines, divide the product into lots and take lot samples in accordance with Practice
D4354.
7.2 Laboratory Sample—For the laboratory sample, take a full-width sample of sufficient length in the machine direction so that
the required size and number of specimens can be obtained. Exclude the inner and outer layers or wraps of the roll or any material
containing folds, crushed areas, or other distortions not representative of the sampled lot.
7.3 Remove test specimens from the laboratory sample so that each specimen will contain different machine and cross-machine
elements, with no specimen taken nearer than 100 mm (4 in.) from the roll sides or ends, unless otherwise specified.
7.4 Cut specimens with their long dimension parallel either to the machine direction or to the cross-machine direction, or cut
specimens for testing both directions as required. Unless otherwise specified, take specimens no nearer to the machine direction
edge of the RECP than one-tenth one tenth of the width of the RECP. Cut each specimen 100 mm (4 in.) wide, by at least 150 mm
(6 in.) long.
NOTE 2—The length of the specimen depends on the type of clamps being used.
NOTE 3—The specimens may be taped across the width on each side of the long dimension to maintain specimen integrity during specimen preparation
and positioning within the gripsclamps during setup and testing. Any tape with sufficient strength, adhesion, and durability to withstand grip pressures
and hold specimen components securely is acceptable. The tape should not extend into the test area (that is, between the grips,clamps, within the 3-in.
gage length). See Fig. 1.
7.4.1 If necessary, centrally, draw two lines running the full width of the specimen, accurately perpendicular to the length
dimension and separated by 75 mm (3 in.) to designate the gage area (see 9.2). For some woven RECPs, it may be necessary to
cut each specimen 110 mm (4.5 in.) wide and then remove an equal number of yarns from each side to obtain the 100-mm (4.0-in.)
finished dimension. This helps maintain specimen integrity during the test.
7.5 Number of Specimens—Unless otherwise agreed upon, as when provided in an applicable material specification, take the
number of test specimens per laboratory sample as follows:
7.5.1 Reliable Estimate of v—When there is a reliable estimate of v based upon extensive part records for similar materials tested
in the user’s laboratory as directed in this test method, calculate the required number of specimens as follows so that the user may
expect at the 95 % probability level that the test result is not more than 5.0 % of the average above or below the average of the
sample:
FIG. 1 Taping of Specimens
D6818 − 21
n 5 t v ⁄ A (1)
~ !
where:
n = number of test specimens (rounded upward to a whole number),
v = coefficient of variation of individual observations on similar materials in the user’s laboratory under conditions of
single-operator precision, %,
t = value of Student’s t for one-sided limits, a 95 % probability level, and the degrees of freedom associated with the estimate
of v (see Table 1), and
A = 5.0 % of the average, the value of the allowable variation.
7.5.2 No Reliable Estimate of v—When there is no reliable estimate of v for the user’s laboratory, measurements shall be made
on a minimum of five (5) specimens per laboratory sample.
8. Conditioning
8.1 Bring the specimens to the moisture and temperature equilibrium in the atmosphere for testing rolled erosion control products,
that is, a temperature of 21 6 2 °C (70 6 4 °F) and a relative humidity of 60 6 10 %.
9. Procedure
9.1 Set gage length to 75 mm.mm (3.0 in.).
9.2 Mount the specimen secur
...