1、Designation: D 4610 98 (Reapproved 2004)Standard Guide forDetermining the Presence of and Removing Microbial(Fungal or Algal) Growth on Paint and Related Coatings1This standard is issued under the fixed designation D 4610; the number immediately following the designation indicates the year oforigina
2、l adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide describes techniques used for determiningthe presence
3、of fungal or algal growth on paint and relatedcoatings and methods for removal of such growth prior torecoating.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety
4、concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 2022 Test Methods of Sampling and
5、 Chemical Analysisof Chlorine-Containing BleachesD 3274 Test Method for Evaluating Degree of SurfaceDisfigurement of Paint Films by Microbial (Fungal orAlgal) Growth or Soil and Dirt Accumulation3. Significance and Use3.1 Microbial growth is a major cause of discoloration anddeterioration of paint f
6、ilms. This guide describes techniquesused to distinguish fungi and algae from other surface con-taminants.3.2 Repainting a surface contaminated with fungi or algaegenerally causes more rapid infestation of the new paint thanrepainting a surface from which fungal or algal growth hasbeen removed. In a
7、ddition, poor adhesion, staining/bleeding,and many other problems may result. This guide describesmethods for removing fungal or algal growth prior to repaint-ing.NOTE 1It is extremely important that all steps and notes be read andfollowed. In particular the washing steps outlined in 5.2.2 and 5.2.4
8、 mustbe fully carried out, since residual sodium hypochlorite (bleach) can causemany of the same problems, or even loss of coloration after repainting,and residual phosphate detergents can encourage further fungal and algalgrowth.NOTE 2This procedure is intended for use when recoating the surface.Re
9、ports of using this procedure to remove fungi and algae withoutrecoating necessitate inclusion of a warning about the adverse effects ofbleach on a coating film. The oxidative effects of bleach can degrade filmproperties, including particularly the “bleaching” (loss of color) in filmscontaining orga
10、nic coloring pigments (such as quinacridones, etc.), loss ofgloss, chalking, etc. A small patch must be tested prior to use of thisprocedure for that purpose.4. Reagents4.1 Sodium Hypochlorite, approximately 5 % aqueous(NaOCl) as commercial household bleach. Because sodiumhypochlorite decomposes on
11、exposure to heat and sunlight andbecomes ineffective, use only fresh material. See Test MethodsD 2022 for methods of sampling and chemical analysis.4.2 Phosphate-Free, non-ammonia-containing detergent orcommercial cleaner recommended for washing paint.5. Procedures5.1 Determining the Presence of Fun
12、gal or Algal Growth onPaint:5.1.1 ChemicalApply a drop of 5 % aqueous sodiumhypochlorite solution (common household bleach) to the areasuspected of being contaminated with fungal or algal growth.Fungal or algal discoloration will normally bleach within 60 s.Discoloration that does not bleach is prob
13、ably dirt. For furtherconfirmation do visual and subculture tests.5.1.2 The following procedures should preferably be usedby persons who have had basic microbiological training:5.1.2.1 VisualExamine the surface using magnificationfrom 10 to 1003 to distinguish among fungal, algal, or dirtdisfigureme
14、nt in accordance with Test Method D 3274.5.1.2.2 SubcultureApply a prepared petri dish containinga raised convex surface of nutrient agar culture medium3directly to the surface to be sampled and exert moderatepressure. Replace the cover and incubate for at least 72 h at35C (95F). Examine the agar su
15、rface visually as in 5.1.2.1.1This guide is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.28 on Biodeterioration.Current edition approved June 1, 2004. Published June 2004. Originallyapproved
16、 in 1986. Last previous edition approved in 1998 as D 4610 98.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website
17、.3Agar available from various microbiological supply companies.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.NOTE 3The culture medium must contain the nutrients necessary forgrowth of algae and fungi.5.2 Removal of Fungal and Algal
18、 Growth on Paint:5.2.1 Wash the surface with a solution of approximately 2 %phosphate-free detergent in water.NOTE 4The term wash as it is used in 5.2.1 and 5.2.3 is defined asfirmly scrubbing the surface with a fully wet sponge or other suitableapplicator. Care should be taken to ensure the surface
19、 is thoroughly wetwith cleaning solution.5.2.2 Thoroughly rinse the surface with water to removeresidual detergent.5.2.3 Wash the surface with a solution of 1 part by volumeof sodium hypochlorite 5 % aqueous solution and 3 parts byvolume of water.NOTE 5See warnings in Note 1 and Note 2. Also be warn
20、ed thatoverspray of bleach can be detrimental to ornamental shrubs, plants orlawn, and can “bleach,” discolor, or otherwise degrade adjacent areas ifnot adequately protected from exposure. Adequate personal protectiveequipment should always be used.NOTE 6The solution should be allowed to remain on t
21、he surface from10 to 15 min.NOTE 7The sodium hypochlorite solution and the 2 % detergentsolution may be combined 1:1 by volume in one treatment if desired.5.2.4 Thoroughly rinse the surface with water to removeresidual sodium hypochlorite (see Note 1).5.2.5 If agreed upon by the parties involved, re
22、inspect thesurface in accordance with 5.1 to ensure that there has beenadequate removal. Refer to the coating manufacturers litera-ture for recommended drying time before recoating.6. Keywords6.1 algal; bleach; fungal; microbial; washASTM International takes no position respecting the validity of an
23、y patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to rev
24、ision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your
25、 comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyr
26、ighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 4610 98 (2004)2
