ASTM_D_6715_-_13.pdf

Designation:D671513Standard Practice forSampling and Preparation of Fresh or Salt-Preserved(Cured)Hides and Skins for Chemical and Physical Tests1This standard is issued under the fixed designation D6715;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.1.Scope1.1 This practice covers the sampling and preparation offresh or salt-preserved(cured)hides for physical and chemicaltests.The hides or skins to be tested are grouped into lots.Eachlot is randomly sampled in such a manner as to produce arepresentative sample of that lot.This lot sample may be usedto determine compliance of the lot with applicable specificationrequirements,and on the basis of results,the lot may beaccepted or rejected in its entirety.1.2 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Terminology2.1 Definitions:2.1.1 brine-curingpreserving by immersing flayed hidesinto concentrated/saturated salt(sodium chloride)solutionuntil sufficient salt has been absorbed by the hide,thus makingit temporarily resistant to bacterial action(cured).2.1.2 curecommonly used industry reference to salt pres-ervation.2.1.3 cured hides(salted hides)commonly used industryterm for salt-preserved hides.2.1.4 de-haired hidea fresh or salt-preserved hide with thehair removed.2.1.5 fresh hidea recently flayed hide or skin that has notbeen preserved(such as salt-cured).2.1.6 hair-on hidea fresh or salt-preserved hide with thehair not removed.2.1.7 laboratory termsany laboratory terms and defini-tions employed within this practice are commonly used innormal laboratory practice and require no special comment.2.1.8 lot(or batch)units of products from a single type,grade,class,size,and composition,manufactured under essen-tially the same conditions and time.2.1.8.1 DiscussionFresh or salt-preserved hides in formedlots should be produced from:(1)Units of product of similar size and type,(2)Fresh or salt-preserved hides obtained from the sameproducer(functionally equivalent),(3)A single product method,or(4)Sequential production batches.2.1.9 salt preservation(cure)is defined as the action ofapplying salt(typically sodium chloride)to flayed hides inorder to make them temporarily resistant to degradation bybacterial(enzymatic)action.Typically,this is achieved byeither brine-curing or wet-salting(salt-packing).2.1.10 salt-preserved(cured)hidesare defined as hidesthat have been processed into a condition that makes themtemporarily resistant to degradation by bacterial(enzymatic)action.This is achieved by the application of adequate salt(typically sodium chloride)to the hide.2.1.11 unitan item of fresh or salt-preserved hide in theform in which it is purchased,such as a single hide,skin,orany part thereof.2.1.12 wet-salting(salt-pack)the action of applying suffi-cient granular salt(sodium chloride)to flayed hides(normallyupon the flesh side)over sufficient time,in order to have thesalt absorbed by the hide,making it temporarily resistant tobacterial action(cured).3.Significance and Use3.1 The sampling procedures described in this practice havebeen designed to ensure random sampling of salt-preservedhides and skins for physical and chemical tests.Fresh orsalt-preserved hides are natural products and as such aresubject to extensive variability.The physical and chemicalproperties vary considerably depending on location on thatspecific hide,side,or skin from which the test sample is taken.Random sampling of specimens from a predefined location and1This practice is under the jurisdiction ofASTM Committee D31 on Leather andis the direct responsibility of Subcommittee D31.02 on Wet Blue.Current edition approved May 1,2013.Published June 2013.Originallyapproved in 2001.Last previous edition approved in 2008 as D6715-08.DOI:10.1520/D6715-13.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 orientation minimizes test bias and variability.This practicedefines these parameters.3.2 In general,tests carried out upon fresh or salt-preservedhides require composite lot samples generated using thepreparation methods described within this practice.Subsequenttests typically require those composite samples to be in twoforms:3.2.1 Expressed Hide Fluidwhere residual hide fluid ispressed from cleaned individual hair-on or de-haired hidesample,then equal volumes of