ASTM D3456-18

Standard Practice for Determining by Exterior Exposure Tests the Susceptibility of Paint Films to Microbiological Attack

SIGNIFICANCE AND USE
4.1 The growth of fungi and algae in and on the surface of paint films represents a major cause of discoloration or disfigurement of painted surfaces. This practice covers the preparation of coatings for testing, their application on substrates, and the arrangement of the coated panels on exterior test fences to determine the degree of microbiological attack that may occur on the surface of the coatings over a period of time. This practice is intended to provide guidelines for, and a discussion of, the various factors critical in selection of exterior coatings resistant to discoloration or disfigurement by algae and fungi.
SCOPE
1.1 This practice provides guidelines for determining the susceptibility of paint films to microbiological attack on exterior exposure. While it is recognized that various organisms may occur on an exposed coating, the specific types of organisms are mainly of academic interest. The degree to which microbiological discoloration occurs is the primary concern.  
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-Jun-2018
• ICS: 87.040 - Paints and varnishes
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.28 - Biodeterioration

Relations

• Refers: ASTM D1849-95(2019) - Standard Test Method for Package Stability of Paint
• Effective Date: 01-Apr-2019
• Referred By: ASTM D5590-17(2021) - Standard Test Method for Determining the Resistance of Paint Films and Related Coatings to Fungal Defacement by Accelerated Four-Week Agar Plate Assay
• Effective Date: 01-Jul-2018
• Referred By: ASTM D3322-23 - Standard Practice for Testing Primers and Primer Surfacers Over Preformed Metal
• Effective Date: 01-Jul-2018
• Referred By: ASTM D5324-16(2022) - Standard Guide for Testing Water-Borne Architectural Coatings
• Effective Date: 01-Jul-2018
• Referred By: ASTM E3152-23 - Standard Guide for Standard Test Methods and Practices Available for Determining Antifungal Activity on Natural or Synthetic Substrates Treated with Antimicrobial Agents
• Effective Date: 01-Jul-2018
• Referred By: ASTM D3274-09(2021) - Standard Test Method for Evaluating Degree of Surface Disfigurement of Paint Films by Fungal or Algal Growth, or Soil and Dirt Accumulation
• Effective Date: 01-Jul-2018
• Referred By: ASTM D6763-16(2022) - Standard Guide for Testing Exterior Wood Stains and Clear Water Repellents
• Effective Date: 01-Jul-2018
• Referred By: ASTM D5146-10(2019) - Standard Guide to Testing Solvent-Borne Architectural Coatings
• Effective Date: 01-Jul-2018

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: D3456 − 18
Standard Practice for
Determining by Exterior Exposure Tests the Susceptibility
1
of Paint Films to Microbiological Attack
This standard is issued under the fixed designation D3456; 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 Film Thickness of Applied Organic Coatings Using an
Ultrasonic Coating Thickness Gage
1.1 This practice provides guidelines for determining the
D7091 Practice for Nondestructive Measurement of Dry
susceptibility of paint films to microbiological attack on
Film Thickness of Nonmagnetic Coatings Applied to
exterior exposure. While it is recognized that various organ-
Ferrous Metals and Nonmagnetic, Nonconductive Coat-
isms may occur on an exposed coating, the specific types of
ings Applied to Non-Ferrous Metals
organisms are mainly of academic interest. The degree to
which microbiological discoloration occurs is the primary
3. Summary of Practice
concern.
3.1 Simple observation of a coated object subjected to
1.2 The values stated in SI units are to be regarded as the
exterior exposure is considered a practical and reliable method
standard. The values given in parentheses are for information
for determining the degree that microorganisms discolor the
only.
coating. However, this applies to a specific coated object
1.3 This standard does not purport to address all of the exposed under a given set of conditions. It should be recog-
safety concerns, if any, associated with its use. It is the nized that there are critical factors that influence the amount of
responsibility of the user of this standard to establish appro- fungal growth that may occur on the same coated object when
priate safety, health, and environmental practices and deter- exposed to other conditions. These factors include the geo-
mine the applicability of regulatory limitations prior to use. graphic location, local atmospheric conditions such as the dust
1.4 This international standard was developed in accor- and pollen content of the air, angle of exposure, degree to
dance with internationally recognized principles on standard- which the coating is subjected to weathering, effects of
ization established in the Decision on Principles for the moisture and sunlight, the substrates on which the coating is
Development of International Standards, Guides and Recom- applied, and the coatings in the paint system under test. The
mendations issued by the World Trade Organization Technical
latterfactorincludesthestabilityofthecoatingwhilepackaged
Barriers to Trade (TBT) Committee. in the container, as well as the composition of the coatings
included in the total system and the thickness of each coating
2. Referenced Documents
applied. Thus, while microorganisms occur on the surface of
2
the last film applied, the degree of microbiological growth that
2.1 ASTM Standards:
will occur is also influenced by the composition of the
D1006 Practice for Conducting Exterior Exposure Tests of
undercoats. All the above factors should be considered in the
Paints on Wood
selection of a coating resistant to discoloration by microorgan-
D1849 Test Method for Package Stability of Paint
isms.
D3274 Test Method for Evaluating Degree of Surface Dis-
figurement of Paint Films by Fungal or Algal Growth, or
4. Significance and Use
Soil and Dirt Accumulation
4.1 The growth of fungi and algae in and on the surface of
D6132 Test Method for Nondestructive Measurement of Dry
paint films represents a major cause of discoloration or
disfigurement of painted surfaces. This practice covers the
1
This practice is under the jurisdiction of ASTM Committee D01 on Paint and
preparation of coatings for testing, their application on
Related Coatings, Materials, and Applications and is the direct responsibility of
substrates,andthearrangementofthecoatedpanelsonexterior
Subcommittee D01.28 on Biodeterioration.
test fences to determine the degree of microbiological attack
Current edition approved July 1, 2018. Published July 2018. Originally approved
that may occur on the surface of the coatings over a period of
in 1975. Last previous edition approved in 2012 as D3456 – 86 (2012). DOI:
10.1520/D3456-18.
time. This practice is intended to provide guidelines for, and a
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
discussionof,thevariousfactorscriticalinselectionofexterior
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
coatings resi
...

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: D3456 − 86 (Reapproved 2012) D3456 − 18
Standard Practice for
Determining by Exterior Exposure Tests the Susceptibility
1
of Paint Films to Microbiological Attack
This standard is issued under the fixed designation D3456; 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 practice provides guidelines for determining the susceptibility of paint films to microbiological attack on exterior
exposure. While it is recognized that various organisms may occur on an exposed coating, the specific types of organisms are
mainly of academic interest. The degree to which microbiological discoloration occurs is the primary concern.
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 safety, health, and healthenvironmental 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.
2. Referenced Documents
2
2.1 ASTM Standards:
D1006 Practice for Conducting Exterior Exposure Tests of Paints on Wood
D1849 Test Method for Package Stability of Paint
D3274 Test Method for Evaluating Degree of Surface Disfigurement of Paint Films by Fungal or Algal Growth, or Soil and Dirt
Accumulation
D6132 Test Method for Nondestructive Measurement of Dry Film Thickness of Applied Organic Coatings Using an Ultrasonic
Coating Thickness Gage
D7091 Practice for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals
and Nonmagnetic, Nonconductive Coatings Applied to Non-Ferrous Metals
3. Summary of Practice
3.1 Simple observation of a coated object subjected to exterior exposure is considered a practical and reliable method for
determining the degree that microorganisms discolor the coating. However, this applies to a specific coated object exposed under
a given set of conditions. It should be recognized that there are critical factors that influence the amount of fungal growth that may
occur on the same coated object when exposed to other conditions. These factors include the geographic location, local atmospheric
conditions such as the dust and pollen content of the air, angle of exposure, degree to which the coating is subjected to weathering,
effects of moisture and sunlight, the substrates on which the coating is applied, and the coatings in the paint system under test. The
latter factor includes the stability of the coating while packaged in the container, as well as the composition of the coatings included
in the total system and the thickness of each coating applied. Thus, while microorganisms occur on the surface of the last film
applied, the degree of microbiological growth that will occur is also influenced by the composition of the undercoats. All the above
factors should be considered in the selection of a coating resistant to discoloration by microorganisms.
1
This practice is under the jurisdiction of ASTM Committee D01 on Paint and Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.28 on Biodeterioration.
Current edition approved Aug. 1, 2012July 1, 2018. Published August 2012July 2018. Originally approved in 1975. Last previous edition approved in 20082012 as
D3456 – 86 (2008).(2012). DOI: 10.1520/D3456-86R12.10.1520/D3456-18.
2
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’sstandard’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
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D3456 − 18
4. Significance and Use
4.1 The growth of fungi and algae in and on the surf
...