ASTM D8162-20a (2025) PDF

Full title and description

Standard Test Method for Determination of the Apparent Viscosity of Thermoplastic Pavement Marking Materials using a Rotational Viscometer with Temperature Control Heating Unit (ASTM D8162-20a, current editorial history through 2025). This short test method describes specimen preparation, apparatus (rotational viscometer with temperature-controlled heating/thimble system and recommended "torpedo" spindles), and a procedure to determine apparent viscosity of thermoplastic pavement marking formulations at elevated temperatures relevant to application and processability.

Abstract

This test method provides a repeatable laboratory procedure to measure apparent viscosity of thermoplastic pavement marking materials under controlled elevated-temperature conditions using a rotational viscometer and temperature-controlled sample chamber. Results help manufacturers, specifiers, and quality-control laboratories characterize flow behaviour (including non-Newtonian effects) at application temperatures and compare formulations for suitability with specific application methods (screed extrusion, ribbon extrude, thin-film or spray).

General information

• Status: Active — designation D8162-20a with editorial history/updates recorded through 26 June 2025 (confirmed current editorial update).
• Publication date: Original designation year 2020 (D8162-20a); editorial/confirmation entries recorded in 2025 (document history last updated 26 June 2025).
• Publisher: ASTM International (Committee D01, Subcommittee D01.44).
• ICS / categories: 93.080.20 (Road construction materials / pavement markings).
• Edition / version: D8162-20a (with amendments/editorial history reflected through 2025).
• Number of pages: 5 pages (concise test method).

Scope

This test method covers sample preparation and the testing procedure required to determine the apparent viscosity of thermoplastic pavement marking formulations at elevated temperatures representative of application conditions. Values are stated in SI units (customary units provided as courtesy). The method describes recommended spindle geometry, temperature control, and practical considerations for formulations that contain glass beads or other fillers that affect spindle motion. It does not replace safety, health, or regulatory assessments for laboratory operations.

Key topics and requirements

• Apparent viscosity measurement of thermoplastic pavement marking formulations at elevated (application) temperatures.
• Use of a rotational viscometer with temperature-controlled heating/thimble chamber and recommended "torpedo" spindles; guidance on spindle diameter relative to thimble and on handling formulations containing glass beads.
• Sample preparation and testing procedure to produce repeatable viscosity values for comparison and quality control.
• Notes on non-Newtonian behaviour and the effect of shear rate (apparent viscosity depends on spindle and speed chosen; comparisons require similar test conditions).
• Significance for application methods (screed extrude, ribbon extrude, thin-film spray, standard spray) and processability decisions.

Typical use and users

Primary users are thermoplastic pavement marking manufacturers, R&D and QC laboratories, materials engineers, pavement-marking applicators, state and municipal DOT specification and test labs, and procurement/specification teams who need to confirm material flow properties for specific application equipment and temperatures. Results are used for product development, lot acceptance testing, troubleshooting application problems, and supporting product approvals.

Related standards

Standards commonly referenced alongside D8162 include ASTM test methods and guides for thermoplastic pavement markings and related properties — for example ASTM D8161 (impact resistance of thermoplastic pavement marking), ASTM D8584 (guide for testing preformed thermoplastic pavement marking material), and regional standards for road marking materials (EN/DIN series such as EN 1871 and EN 1423). These documents together cover mechanical, optical, and installation-related properties and laboratory/field test guidance.

Keywords

apparent viscosity; thermoplastic pavement marking; rotational viscometer; temperature-controlled thimble; torpedo spindle; sample preparation; non-Newtonian; application temperature; pavement marking quality control.

FAQ

Q: What is this standard?

A: ASTM D8162-20a is a short ASTM test method that specifies how to measure the apparent viscosity of thermoplastic pavement marking materials using a rotational viscometer with a temperature-controlled heating unit and recommended spindle geometry. It is intended to produce repeatable viscosity values at application-relevant temperatures.

Q: What does it cover?

A: The standard covers specimen preparation, apparatus requirements (rotational viscometer and temperature-controlled thimble), recommended spindle types and sizes (torpedo spindles), test procedure, and notes on interpreting apparent-viscosity results for non-Newtonian thermoplastic formulations. It does not substitute for safety or regulatory guidance for laboratory operation.

Q: Who typically uses it?

A: Thermoplastic marking manufacturers, QC and R&D labs, applicators, state and local DOT laboratories, and specification authors use this method to assess flow and processability at application temperatures and to support product approval and quality control.

Q: Is it current or superseded?

A: The D8162-20a designation originates from 2020; the document record shows editorial/confirmation activity through 2025 with the standard listed as current/active in ASTM's document history (last updated 26 June 2025). Users should consult ASTM International for the official status and any later amendments.

Q: Is it part of a series?

A: D8162 is part of the suite of ASTM standards and guides addressing pavement marking materials and properties (other related test methods and guides include D8161, D8584 and various specification documents dealing with application, optical performance, and durability). It is typically used in combination with those other methods to comprehensively evaluate thermoplastic pavement marking products.

Q: What are the key keywords?

A: Apparent viscosity; thermoplastic pavement marking; rotational viscometer; temperature-controlled chamber; torpedo spindle; non-Newtonian flow; application temperature; quality control.