ASTM D5590-17(2021)
(Test Method)Standard Test Method for Determining the Resistance of Paint Films and Related Coatings to Fungal Defacement by Accelerated Four-Week Agar Plate Assay
Standard Test Method for Determining the Resistance of Paint Films and Related Coatings to Fungal Defacement by Accelerated Four-Week Agar Plate Assay
SIGNIFICANCE AND USE
4.1 Defacement of paint and coating films by fungal growth (mold, mildew) is a common phenomenon, and defacement by algal growth can also occur under certain conditions. It is generally known that differences in the environment, lighting, temperature, humidity, substrate pH, and other factors in addition to the coating composition affect the susceptibility of a given painted surface. This test method attempts to provide a means to comparatively evaluate different coating formulations for their relative performance under a given set of conditions. It does not imply that a coating that resists growth under these conditions will necessarily resist growth in the actual application. The method is not intended to simulate or replace indoor or outdoor exposure of paint films or related coatings.
Note 1: It is hoped that a ranking of relative performance would be similar to that ranked from outdoor exposures. Paint designated for service in exterior conditions should be pre-conditioned by laboratory accelerated weathering prior to exposure to fungi. All pre-conditioning must be detailed in the final report. This test method however, should not be used as a replacement for exterior exposure (that is, Practice D3456) since many other factors, only a few of which are listed will affect those results.
4.2 Familiarity with microbiological techniques is required. This test method should not be used by persons without at least basic microbiological training.
SCOPE
1.1 This test method covers an accelerated method for determining the relative resistance of two or more paints or coating films to fungal growth.
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
Relations
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: D5590 − 17 (Reapproved 2021)
Standard Test Method for
Determining the Resistance of Paint Films and Related
Coatings to Fungal Defacement by Accelerated Four-Week
Agar Plate Assay
This standard is issued under the fixed designation D5590; 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 D4708 Practice for Preparation of Uniform Free Films of
Organic Coatings
1.1 This test method covers an accelerated method for
D6132 TestMethodforNondestructiveMeasurementofDry
determining the relative resistance of two or more paints or
Film Thickness of Applied Organic Coatings Using an
coating films to fungal growth.
Ultrasonic Coating Thickness Gage
1.2 The values stated in SI units are to be regarded as the
D6695 Practice for Xenon-Arc Exposures of Paint and
standard. The values given in parentheses are for information
Related Coatings
only.
G21 Practice for Determining Resistance of Synthetic Poly-
1.3 This standard does not purport to address all of the
meric Materials to Fungi
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3. Summary of Test Method
priate safety, health, and environmental practices and deter-
3.1 This test method outlines a procedure to (1) prepare a
mine the applicability of regulatory limitations prior to use.
suitable specimen for testing, (2) inoculate the specimen with
1.4 This international standard was developed in accor-
the proper fungal species, (3) expose the inoculated samples
dance with internationally recognized principles on standard-
under the appropriate conditions for growth, and (4) provide a
ization established in the Decision on Principles for the
schedule and guidelines for visual growth ratings. This test
Development of International Standards, Guides and Recom-
method is not designed to include all the necessary procedures
mendations issued by the World Trade Organization Technical
to maintain the proper microbiological techniques required to
Barriers to Trade (TBT) Committee.
provide the most accurate results.
2. Referenced Documents
4. Significance and Use
2.1 ASTM Standards:
4.1 Defacement of paint and coating films by fungal growth
D1005 Test Method for Measurement of Dry-Film Thick-
(mold, mildew) is a common phenomenon, and defacement by
ness of Organic Coatings Using Micrometers
algal growth can also occur under certain conditions. It is
D3273 TestMethodforResistancetoGrowthofMoldonthe
generally known that differences in the environment, lighting,
Surface of Interior Coatings in an Environmental Cham-
temperature, humidity, substrate pH, and other factors in
ber
addition to the coating composition affect the susceptibility of
D3456 Practice for Determining by Exterior Exposure Tests
a given painted surface. This test method attempts to provide a
theSusceptibilityofPaintFilmstoMicrobiologicalAttack
meanstocomparativelyevaluatedifferentcoatingformulations
D4587 Practice for Fluorescent UV-Condensation Expo-
for their relative performance under a given set of conditions.
sures of Paint and Related Coatings
It does not imply that a coating that resists growth under these
conditions will necessarily resist growth in the actual applica-
tion. The method is not intended to simulate or replace indoor
This test method is under the jurisdiction of ASTM Committee D01 on Paint
or outdoor exposure of paint films or related coatings.
and Related Coatings, Materials, andApplications and is the direct responsibility of
Subcommittee D01.28 on Biodeterioration.
NOTE 1—It is hoped that a ranking of relative performance would be
Current edition approved Nov. 1, 2021. Published November 2021. Originally
similartothatrankedfromoutdoorexposures.Paintdesignatedforservice
approved in 1994. Last previous edition approved in 2017 as D5590 – 17. DOI:
in exterior conditions should be pre-conditioned by laboratory accelerated
10.1520/D5590-17R21.
weathering prior to exposure to fungi. All pre-conditioning must be
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
detailed in the final report. This test method however, should not be used
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 as a replacement for exterior exposure (that is, Practice D3456) since
the ASTM website. many other factors, only a few of which are listed will affect those results.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5590 − 17 (2021)
4.2 Familiarity with microbiological techniques is required. Society, where such specifications are available. Other grades
This test method should not be used by persons without at least may be used, provided they are first ascertained to be of
basic microbiological training. sufficiently high purity to permit use without decreasing the
accuracy of the determination.
5. Apparatus and Materials
6.2 Purity of Water—Unless otherwise indicated, references
5.1 Balance, capable of weighing to 0.10 g.
to water are understood to mean distilled water or water of
equal or higher purity.
5.2 Incubator, or other device capable of maintaining a
constant temperature between 25 and 30°C, relative humidity
6.3 PDAor MaltAgar plates can be purchased prepared, or
of ≥85 %.
the PDAand MaltAgar powder can be purchased and prepared
according to the instructions using standard microbiological
5.3 Refrigerator, or other device capable of maintaining a
techniques and equipment.
temperature of 4 6 2°C.
5.4 Petri Dishes, 100 by 15 mm (3.9 by 0.6 in.).
7. Preparation of the Fungal Spore Inocula
5.5 Autoclave, capable of producing 103 kPa (15 psi) of
7.1 Fungal Cultures—Use the following test fungi in pre-
5,6,7,8
steam pressure at 121°C and maintaining it for a minimum of
paring the inocula:
15 min. An autoclave is not necessary if pre-prepared media
5 6
Fungi ATCC # NRRL
plates are used.
Aspergillus niger 6275 334
Penicillium pinophilum 11797 3647
1 3
5.6 Paint Brush, coarse bristle, 12 to 19 mm ( ⁄2 to ⁄4 in.). 8
Aureobasidium pullulans 9348 62100
5.7 Substrate, Filter Paper (Glass fiber, Grade 391, 4.2 cm
NOTE 2—These organisms were selected based on the historical data
(1.65 in.)) or drawdown paper (unlaquered chart paper 216 by from use in Test Method D3273. Other organisms may be of specific
interest for certain applications or geographical areas. Such other pure
280 mm (8.5 by 11 in.), cut into ten 216 by 28-mm (8.5 by
cultures, or isolated wild strains, may be used as agreed upon by the
1.1-in.) strips.
parties involved.
5.8 Atomizer or Chromatography Sprayer.
7.2 Maintain stock cultures of these fungi separately on an
5.9 Sterile Glass Rods, Forceps, 250-mL Glass Erlenmeyer appropriate medium such as potato dextrose agar plates or
Flasks, Test Tubes, and other routine microbiological equip- slants. The stock culture may be kept for not more than 4
ment. months at approximately 3 to 10°C (37 to 50°F). Subculture
individual fungi onto slants or plates 7 to 20 days at 28 to 30°C
5.10 Potato Dextrose Agar (PDA) or Malt Agar.
(82 to 86°F) prior to each experiment, and use these subcul-
5.11 Nutrient-Salts Agar (as found in Practice G21).
tures in preparing the spore suspension.
5.11.1 Preparethismediumbydissolvingin1Lofwaterthe
7.3 Prepare a spore suspension of each of the test fungi by
designated amounts of the following reagents:
pouring into one subculture of each fungus a sterile 10-mL
Monopotassium phosphate (KH PO ) 0.7 g
2 4
portion of water, or of a sterile solution containing 0.05 g/L of
Mangnesium sulfate (MgSO ·7H O) 0.7 g
4 2
a nontoxic wetting agent such as sodium dioctylsulfosuccinate.
Ammonium nitrate (NH NO ) 1.0 g
4 3
Sodium chloride (NaCL) 0.005 g
Swirl or gently agitate the slant or plate to loosen the spores.
Ferrous sulfate (FeSO ·7H O) 0.002 g
4 2
Carefully aspirate the water and spore suspension with a sterile
Zinc sulfate (ZnSO ·7H O) 0.002 g
4 2
Manganese sulfate (MnSO ·H O) 0.001 g Pasteur pipet (trying to avoid obtaining mycelia).
4 2
Agar 15.0 g
7.4 Filter the shaken or ground suspension through a thin
Dipotassium phosphate (K HPO ) 0.7 g
2 4
layer of sterile glass wool in a glass funnel into a sterile flask
5.11.2 Sterilize the test medium by autoclaving at 121°C
in order to remove mycelial fragments.
(250°F) for 20 min.Adjust the pH of the medium so that after
sterilization the pH is between 6.0 and 6.5. 7.5 Dilute the spores suspension with sterile nutrient salts
solutionsuchthattheresultantsporesuspensioncontains0.8to
5.12 Nutrient-Salts Solution, (see 5.11 without agar).
1.2 by 10 spores/mL as determined with a counting chamber.
5.13 Counting Chamber (Hemocytometer).
7.6 Repeat this operation for each organism used in the test.
5.14 Glass Wool.
The A. pullulans spores should be maintained separately and
5.15 Laboratory Accelerated Weathering and Leaching
Equipment, if used.
Reagent Chemicals, American Chemical Society Specifications, American
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
listed by the American Chemical Society, see Analar Standards for Laboratory
6. Reagents and Materials
Chemicals, BDH Ltd., Poole, Dorset, U.K., an
...
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