ASTM D7308-17(2022)

Standard Practice for Sample Preparation of Thermoplastic Pavement Marking Materials

SIGNIFICANCE AND USE
5.1 This practice provides a standard procedure for the preparation of thermoplastic pavement marking material test specimens prior to testing for various properties as called for in the governing specification. Specimens that are prepared using this standard methodology yield test results that are consistent with the material from which it was sampled. Test results from specimens can be used to determine compliance of the thermoplastic pavement marking material to the specification. This practice can also be used by manufacturers of these materials to prepare specimens for testing to determine the uniformity of thermoplastic pavement marking materials from batch to batch.  
5.2 This practice does not address any issues related to specific testing of the thermoplastic pavement marking materials for any physical or chemical property.
SCOPE
1.1 This practice covers the proper preparation of test specimens of thermoplastic pavement marking materials obtained to ensure test results are representative of the material being tested.  
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.  
1.3 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.  
1.4 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: 30-Nov-2022
• ICS: 93.080.30 - Road equipment and installations
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.44 - Traffic Coatings

Relations

• Refers: ASTM D7307-06(2011) - Standard Practice for Sampling of Thermoplastic Traffic Marking Materials
• Effective Date: 01-Nov-2006
• Refers: ASTM D7307-06 - Standard Practice for Sampling of Thermoplastic Traffic Marking Materials
• Effective Date: 01-Nov-2006

Overview

ASTM D7308-17(2022), Standard Practice for Sample Preparation of Thermoplastic Pavement Marking Materials, establishes a systematic procedure for preparing test specimens of thermoplastic pavement marking materials. Developed by ASTM International, this standard ensures that samples used for testing accurately represent the material properties intended for evaluation, including quality control, specification compliance, and uniformity across production batches. By providing a consistent approach to sample preparation, ASTM D7308-17(2022) supports reliable testing and trustworthy results, serving as a critical reference for laboratories, manufacturers, and regulatory authorities involved in traffic coatings and pavement marking evaluations.

Key Topics

• Scope of Application: ASTM D7308-17(2022) details the preparation of test specimens from thermoplastic pavement marking materials to ensure that testing results reflect the true characteristics of the material batch.
• Consistent Sample Preparation: The practice outlines melting and agitation processes, specifying apparatus such as a heating mantle or hot plate and the use of mechanical stirring to simulate actual field application. This ensures test specimens maintain the same qualities as the material applied on road surfaces.
• Minimum Sample Size & Representativeness: The standard emphasizes the importance of obtaining a representative sample, referencing ASTM D7307 for sampling procedure, and advises minimum sample sizes to achieve reliable test outcomes.
• Flexibility for Specification Requirements: Procedures allow for adaptation based on the governing specification's requirements, including extended heating or immediate sample preparation, to assess heat history impacts.
• Safety and Environmental Considerations: The document addresses the need for appropriate safety, health, and environmental practices when preparing and handling heated thermoplastic materials.
• Standardization Principles: Developed in line with World Trade Organization (WTO) best practices, the standard promotes international consistency and reliability in material testing.

Applications

ASTM D7308-17(2022) is widely used in several practical contexts:

• Quality Control: Manufacturers utilize this standard to prepare specimens for batch-to-batch consistency evaluation, ensuring uniformity of thermoplastic pavement marking products.
• Compliance Testing: Testing laboratories apply the procedures to determine if thermoplastic pavement marking materials meet required specifications, supporting road safety and regulatory compliance.
• Research and Development: Formulators and developers leverage this standardized method to compare new product formulations and assess their properties reliably.
• Regulatory Oversight: Agencies responsible for road infrastructure rely on standardized sample preparation to verify that marking materials used in public projects fulfill durability and visibility requirements.
• Field Simulation: The specified sample preparation procedures closely simulate field conditions, improving the relevance of laboratory testing to actual pavement marking performance.

Related Standards

• ASTM D7307: Practice for Sampling of Thermoplastic Pavement Marking Materials - provides procedures for obtaining representative samples from materials to be prepared in accordance with ASTM D7308.
• ASTM Standards for Pavement Markings: ASTM D7308-17(2022) aligns with other ASTM D01 Committee standards addressing paints, coatings, and materials for road marking applications.

---

Keywords: ASTM D7308-17(2022), thermoplastic pavement marking materials, sample preparation, test specimens, quality control, compliance testing, traffic coatings, standard practice, laboratory sample preparation, ASTM standards.

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: D7308 − 17 (Reapproved 2022)
Standard Practice for
Sample Preparation of Thermoplastic Pavement Marking
Materials
This standard is issued under the fixed designation D7308; 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 4. Summary of Practice
1.1 This practice covers the proper preparation of test
4.1 The thermoplastic pavement marking material is pre-
specimens of thermoplastic pavement marking materials ob-
pared for the testing of various physical and chemical proper-
tained to ensure test results are representative of the material
ties as outlined in the governing specification by melting a
being tested.
sample of the traffic marking material to its application
temperature under continuous agitation. Depending upon the
1.2 The values stated in SI units are to be regarded as the
requirements of the governing specification the sample can
standard. The values given in parentheses are for information
then be exposed to the required heating time and conditions
only.
prior to the preparation of the test specimens or the test
1.3 This standard does not purport to address all of the
specimens may be prepared immediately after the material has
safety concerns, if any, associated with its use. It is the
reached application temperature.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
4.2 If required by the governing specification that the
mine the applicability of regulatory limitations prior to use.
sample be subjected to an extended period of heating prior to
1.4 This international standard was developed in accor-
the preparation of the test specimen in order to determine the
dance with internationally recognized principles on standard-
effect of heat history upon various physical or chemical
ization established in the Decision on Principles for the
properties, the sample must be melted down in the prescribed
Development of International Standards, Guides and Recom-
manneroutlinedinthispracticepriortobeingsubjectedtosuch
mendations issued by the World Trade Organization Technical
conditions.
Barriers to Trade (TBT) Committee.
5. Significance and Use
2. Referenced Documents
2 5.1 This practice provides a standard procedure for the
2.1 ASTM Standards:
preparation of thermoplastic pavement marking material test
D7307 Practice for Sampling of Thermoplastic Pavement
specimens prior to testing for various properties as called for in
Marking Materials
the governing specification. Specimens that are prepared using
this standard methodology yield test results that are consistent
3. Terminology
with the material from which it was sampled. Test results from
3.1 Definitions of Terms Specific to This Standard:
specimens can be used to determine compliance of the ther-
3.1.1 thermoplastic pavement marking material, n—a
moplastic pavement marking material to the specification. This
highly filled 100 % total solids highway marking material that
practice can also be used by manufacturers of these materials
when heated to a molten state can be extruded or sprayed onto
to prepare specimens for testing to determine the uniformity of
a road surface and when cooled forms a solid, durable
thermoplasticpavementmarkingmaterialsfrombatchtobatch.
delineator.
5.2 This practice does not address any issues related to
specific testing of the thermoplastic pavement marking mate-
This practice is under the jurisdiction of ASTM Committee D01 on Paint and
rials for any physical or chemical property.
Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.44 on Traffic Coatings.
Current edition approved Dec. 1, 2022. Published December 2022. Originally 6. Apparatus
approved in 2007. Last previous edition approved in 2017 as D7308 – 17. DOI:
10.1520/D7308-17R22. 6.1 Procedure A (Preferred):
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
6.1.1 Stainless Steel 4000 ml Beaker, 150 mm by 230 mm
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
diameter high. Alternatively an unlined 0.95 L (1 qt) or 3.48 L
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. (1 gal) can may be used depending on the sample size.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7308 − 17 (2022)
6.1.2 Heating Mantle of sufficient size. Note that aluminum troller in accordance with the manufactures instructions.
foil may be used to serve as somewhat of a gasket if an unlined Mount the controller-indicator in a panel that can be wall
metal can is to be used in the heating mantle in place of the mounted to keep the unit away from heat, dirt, and vibrations.
stainless steel beaker. When the unit is ready for operation, make a test melt in order
6.1.3 Temperature Indicator. to set the proportional band and other adjustment to give a
6.1.4 Thermocouple, iron. controlled temperature of 218 °C 6 1 °C (425 °F 6 2 °F), or to
6.1.5 Mechanical Stirrer, capable of stirring. The stirrer an alternate temperature as called for in the governing speci-
should consist of two impellers with a diameter of approxi- fication.
mately 63.5 mm mounted on a 7.95-mm diameter shaft of 8.2.1.2 Place one-third to one-half of the granular sample
sufficient length. into the container residing in the heating mantle. Attach the
6.1.6 Aluminum Lid to cover the top of the container with a stirring shaft to the mechanical stirrer.
slot to clear the shaft of the mechanical stirrer and the 8.2.1.3 Turn on the power to the heating mantle and the
thermocouple.
controller. Start the variable speed mechanical sti
...