ASTM_D_3274_-_09_2021.pdf

Designation:D327409(Reapproved 2021)Standard Test Method forEvaluating Degree of Surface Disfigurement of Paint Filmsby Fungal or Algal Growth,or Soil and Dirt Accumulation1This standard is issued under the fixed designation D3274;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 Fungal growth,frequently referred to as mildew in thepaint industry,causes defacement of paint film exposed out-doors.The visual rating of paint surface disfigurement due tofungal or algal attack is required in order to compare theperformance of different coatings.1.2 This method of rating mildew evaluation is intended tobe used on exterior exposed paint films.This method may beused to rate interior fungal or algal growth,but it should benoted that the growth patterns on interior surfaces are differentthan exterior due to the lack of weathering influences.It isprimarily intended for test specimens,but can also be used forrating mildew growth on larger structures such as entirehouses.If this is used for large areas,the project should bebroken down into smaller sections.1.3 This method is intended for field use for the macrorating of surface disfigurement only.The visual scales aremeant to be used by the unaided eye to rate algal,fungal,or dirtdisfigurement on larger surface areas such as test panels,sidingboards,or entire buildings.Techniques are included for thedifferentiation of soil and dirt.1.4 Fungi will grow on most paint films exposed outdoorsthat are located in conditions favorable to growth.Test proce-dures such as Practices D1006,D3456,and G7 are availabledescribing natural exposure tests that can be used to exposepaint films,in order to create fungal or algal growth.1.5 The pictorial references available for use with this testmethod provide a numerical basis for rating the degree offungal or algal growth on paint films.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D1006 Practice for Conducting Exterior Exposure Tests ofHand and Factory Applied Paints on Wood and WoodComposite MaterialsD3456 Practice for Determining by Exterior Exposure Teststhe Susceptibility of Paint Films to MicrobiologicalAttackD4610 Guide for Determining the Presence of and Remov-ing Microbial(Fungal or Algal)Growth on Paint andRelated CoatingsG7 Practice for Natural Weathering of Materials3.Terminology3.1 Types of Fungal GrowthDuring examination of a paintfilm,it may be possible to distinguish between the severaltypes of fungal or algal growth.If required,it may be necessaryto note the type of fungal or algal growth found.Undermagnification,and with some identification training,it ispossible to be able to distinguish growth types.The followingdefinitions are some growth types that may be found.3.2 hyphae,nthread-like,tubular fungal filaments thatcompose the mycelium.3.3 mildew,na popular term for the conglomerations offungi that grow on and disfigure paint films.3.4 mycelium,nvegetative mass of hyphae forming thebody of a fungus.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.28 on Biodeterioration.Current edition approved Nov.1,2021.Published November 2021.Originallyapproved in 1973.Last previous edition approved in 2017 as D3274 09(2017).DOI:10.1520/D3274-09R21.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1?3.5 sporean asexual reproductive cell capable of develop-ing into a mature fungus witho