1、Designation:D758416(Reapproved 2021)Standard Test Method forEvaluating the Resistance of the Surface of Wet Blue andWet White to the Growth of Fungi in an EnvironmentalChamber1This standard is issued under the fixed designation D7584;the number immediately following the designation indicates the yea
2、r 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.1.Scope1.1 This environmental chamber method measures the re-sistance of
3、the treated Wet Blue and Wet White to thegermination of spores and subsequent vegetative growth over aperiod of four weeks.The test method is useful in estimatingthe performance of fungicides and should assist in the predic-tion of storage time of Wet Blue and Wet White before fungalgrowth begins.Th
4、e apparatus is designed so it can be easilybuilt or obtained by any interested party and duplicate thenatural environment in which Wet Blue and Wet White isinoculated with fungal spores.Spores that germinate on un-treated or treated Wet Blue and Wet White can produce fungalgrowth,resulting in disfig
5、urement or discoloration,or both,ofthe Wet Blue and Wet White.1.2The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresp
6、onsibility 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.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-izat
7、ion 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:2D3273 Test Method for Resistance to Growth of Mold on theS
8、urface of Interior Coatings in an Environmental Cham-berE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 Definitions:3.1.1 fungichemoorganotrophic eukaryotic organ
9、isms liv-ing mainly under aerobic conditions and generating energy bythe oxidation of organic materials.3.1.2 molda macroscopic discoloration of the surface ofwet blue.Mold also a sign of the presence of microscopicfungal growth in the form of usually clear to white fungalhyphae,spores of various co
10、lors,and other structures.Coloredspots,probably due to the presence of a colored pigmentproduced by the fungus,have been observed on the surface ofwet blue in places where fungal growth has occurred and thenstopped.Fungal structures such as hyphae and spores may beviewed by simply using a 10 hand le
11、ns.3.1.3 Wet Bluehide or skin,or split of a hide or skin,tanned with basic chromium sulfate,containing approximately50%moisture and an acidic pH.3.1.4 Wet Whitehide or skin that has been processed withtanning as the terminal step by using organic or non-organictanning agents.Chromium or iron contain
12、ing agents andvegetable extracts will be excluded from use in Wet White.3.1.5 Fungi of Importance in the Tannery:3.1.5.1 Filamentous Fungi:(1)A wide variety of fungi have been identified in thetannery,but commonly encountered species include Aspergil-lus spp.,Paecilomyces spp.,and Penicillium spp.(2
13、)Aspergillus niger produces black spores and Penicil-lium luteum produces yellow-green colored spores.(3)Trichoderma viride produces green spores.3.1.5.2 YeastMany yeasts are cream colored,but pig-mented ones may also be encountered including Rhodotorulaspp.which is pigmented red.1This test method i
14、s under the jurisdiction of ASTM Committee D31 on Leatherand is the direct responsibility of Subcommittee D31.02 on Wet Blue.Current edition approved Sept.1,2021.Published October 2021.Originallyapproved in 2010.Last previous edition approved in 2016 as D7584 16.DOI:10.1520/D7584-16R21.2For referenc
15、ed 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 Conshohocke
16、n,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.13.1.5.3 Factors Favoring the Growth of Fungi in the Tan-nery:(1)Wet Blue and Wet White contain nutrients beneficial tofungal growth.(2)Favorable environment