ASTM D5682-18 (2023) PDF

Full title and description

Standard Test Methods for Electrical Resistivity of Liquid Paint and Related Materials — designation D5682 − 18 (reapproved 2023). The document specifies two test methods for measuring the specific electrical resistance (resistivity) of liquid paints, solvents and related fluids, using (A) a paint application test assembly and (B) a conductivity meter.

Abstract

This standard provides repeatable procedures to determine the specific resistance (resistivity) of liquid coatings and related materials over a wide resistivity range. It describes required apparatus, calibration (cell constant), test conditions (including comments on temperature and humidity), measurement ranges and units, and two alternative measurement arrangements — an application/test assembly and a bench conductivity meter — to support quality control and electrostatic spray compatibility assessments.

General information

• Status: Active (reapproved 2023).
• Publication date: Originally issued 2018; reapproved June 2023 (D5682-18R23).
• Publisher: ASTM International.
• ICS / categories: 87.040 — Paints and varnishes.
• Edition / version: D5682-18 (Reapproved 2023).
• Number of pages: 4 pages.

Scope

The test methods cover determination of specific resistance (resistivity) of liquid paints, solvents and other fluids in the approximate range 0.6 to 2640 MΩ·cm. Test Method A uses a paint application test assembly (representative of electrostatic spray application), while Test Method B uses a conductivity meter; the standard also addresses probe/cell constant determination, measurement ranges and instrument standardization. The standard is intended for laboratory and production control measurements to assess electrostatic spray compatibility and related electrical properties.

Key topics and requirements

• Definition and units for specific resistance (resistivity) of liquid coatings (MΩ·cm range).
• Test Method A — paint application test assembly configuration and procedure (simulates electrostatic application).
• Test Method B — conductivity meter procedure and dual-range measurement guidance.
• Cell constant determination and standardization procedures (including recommended routine K value guidance).
• Environmental considerations: recommended test temperature (25 °C) and notes on humidity/water pickup effects on repeatability.
• Reporting requirements, instrument ranges, and limitation notes for low/high resistivity measurements.

Typical use and users

Used by paint and coatings manufacturers, formulation and R&D laboratories, quality control technicians, electrostatic spray applicators, and testing laboratories to verify electrical properties of liquid coatings and solvents for safe and effective electrostatic application, process control, and product specification. It supports troubleshooting of spray deposition issues and specification of anti‑static or conductive formulations.

Related standards

Relevant standards for electrical resistance/resistivity measurements and electrostatic handling include ASTM D257 (DC resistance or conductance and volume/surface resistivity of insulating materials). Other ASTM test methods and guidance on electrostatic spray compatibility and coating physical properties may be used alongside D5682 for comprehensive evaluation.

Keywords

electrical resistivity; specific resistance; conductivity meter; paint application test assembly; electrostatic spray compatibility; cell constant; MΩ·cm; liquid paint; solvents; ASTM D5682-18R23.

FAQ

Q: What is this standard?

A: ASTM D5682-18 (reapproved 2023) is a small test-method standard that specifies procedures to measure the electrical resistivity (specific resistance) of liquid paints, solvents and related fluids, using either a paint application assembly or a conductivity meter.

Q: What does it cover?

A: It covers measurement ranges (approximately 0.6 to 2640 MΩ·cm), apparatus descriptions, calibration/ cell‑constant determination, environmental considerations (temperature and humidity), two alternative test methods (A and B), and reporting rules to ensure repeatable resistivity results.

Q: Who typically uses it?

A: Paint/coatings manufacturers, QC and R&D labs, independent test labs, and application engineers concerned with electrostatic spray processes and the electrical behavior of liquid coatings.

Q: Is it current or superseded?

A: The 2018 edition was reapproved in 2023 (documented as D5682-18R23); it is listed as active/current following the 2023 reapproval. Users should confirm the status with ASTM for any later revisions.

Q: Is it part of a series?

A: It is a standalone test-method under ASTM Committee D01 (Paint and Related Coatings, Materials, and Applications), Subcommittee D01.24 (physical properties of liquid paints and paint materials). It is commonly used alongside other electrical-resistivity and coating test standards (for example ASTM D257).

Q: What are the key keywords?

A: electrical resistivity; specific resistance; conductivity meter; application test assembly; electrostatic spray; MΩ·cm; cell constant; liquid coatings.