ASTM D5064-16a(2021)

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: D5064 − 16a (Reapproved 2021)
Standard Practice for
Conducting a Patch Test to Assess Coating Compatibility
This standard is issued under the fixed designation D5064; 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 D4138 Practices for Measurement of Dry Film Thickness of
Protective Coating Systems by Destructive, Cross-
1.1 This practice covers the procedures for assessing coat-
Sectioning Means
ing compatibility when maintenance of an in-place coating
D4414 Practice for Measurement of Wet Film Thickness by
system is being contemplated. It does not address procedures
Notch Gages
for assessing the integrity of the existing coating to determine
D4541 Test Method for Pull-Off Strength of Coatings Using
if it can be repainted, nor does it establish the compatibility of
Portable Adhesion Testers
the maintenance coating system with the substrate or corrosion
D6132 Test Method for Nondestructive Measurement of Dry
products. The practice is intended for use in the field.
Film Thickness of Applied Organic Coatings Using an
SSPC-TU 3 discusses the risks associated with the mainte-
Ultrasonic Coating Thickness Gage
nance painting practice known as overcoating.
D6677 Test Method for Evaluating Adhesion by Knife
NOTE 1—Pass-Fail Criteria (for example, adhesion requirements) are
D7091 Practice for Nondestructive Measurement of Dry
not established by this practice.These should be established by the user or
Film Thickness of Nonmagnetic Coatings Applied to
specifier with input from the coating manufacturer.
Ferrous Metals and Nonmagnetic, Nonconductive Coat-
1.2 The values stated in SI units are to be regarded as the
ings Applied to Non-Ferrous Metals
standard. The values given in parentheses are for information
D7234 Test Method for Pull-OffAdhesion Strength of Coat-
only.
ings on Concrete Using Portable Pull-Off Adhesion Tes-
1.3 This standard does not purport to address all of the ters
safety concerns, if any, associated with its use. It is the
2.2 SSPC Standards:
responsibility of the user of this standard to establish appro- TU 3 Technology Update No. 3 Overcoating
priate safety, health, and environmental practices and deter-
3. Terminology
mine the applicability of regulatory limitations prior to use.
3.1 Definitions—For definitions of terms used in this
1.4 This international standard was developed in accor-
dance with internationally recognized principles on standard- practice, refer to Terminology D16.
ization established in the Decision on Principles for the
4. Summary of Test Method
Development of International Standards, Guides and Recom-
4.1 The materials under test are applied to the previously
mendations issued by the World Trade Organization Technical
painted surface after surface preparation.After the appropriate
Barriers to Trade (TBT) Committee.
time has elapsed, the test patch is examined for visual defects
and adhesion is assessed.
2. Referenced Documents
2.1 ASTM Standards:
5. Significance and Use
D16 TerminologyforPaint,RelatedCoatings,Materials,and
5.1 In performing maintenance of a coating system, the new
Applications
coating being applied must be compatible with the existing
D3359 Test Methods for Rating Adhesion by Tape Test
coating. While general guides exist which indicate compatibil-
ity of different generic types of coatings, differences in
manufacturer’s formulation and the condition of the in-place
This practice is under the jurisdiction of ASTM Committee D01 on Paint and
coating system may affect compatibility.
Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.46 on Industrial Protective Coatings.
6. Procedure
Current edition approved June 1, 2021. Published June 2021. Originally
approved in 1990. Last previous edition approved in 2016 as D5064 – 16a. DOI:
6.1 Select test locations for evaluation that adequately
10.1520/D5064-16AR21.
characterize differences in configuration of the structure and
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on Available from Society for Protective Coatings (SSPC), 800 Trumbull Drive,
the ASTM website. Pittsburgh, PA 15205, http://www.sspc.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5064 − 16a (2021)
less the average thickness of the in-place coating.
the exposure environment; that is, vertical versus horizontal
surfaces; sheltered versus unsheltered exposure; atmospheric
6.9 A sufficient test duration and inspection frequency
verses splash zone or immersion. Additional factors must be
should be agreed upon between the purchaser and seller prior
considered for previously immersed areas. For these cases
to evaluation.The test duration should be long enough to allow
consult the coating manufacturer. A minimum of three test
the coating to cure and weather prior to evaluation. Test
locations with one test patch in each is recommended.
durations are defined as long term and short term. Long-term
test durations
...