1、Designation: C 390 08Standard Practice forSampling and Acceptance of Thermal Insulation Lots1This standard is issued under the fixed designation C 390; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A nu
2、mber in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This standard provides criteria for establishing theacc
3、eptability of lots of shipments of preformed board, pre-formed block and pipe, and batts and blanket thermal insula-tion based on sampling and inspection.1.2 This standard is intended for use in conjunction withappropriate ASTM material specifications that classify anddescribe the specific physical
4、requirements for the product interms of qualification requirements and inspection require-ments. Determination of nonconformity shall be based on thetolerances for individual sample test values prescribed in thematerial specification.1.3 This standard may require inspection substantially dif-ferent
5、from that performed in the normal course of production.If the purchaser requires sampling and acceptance inspection inaccordance with this practice, he shall so specify in the order orcontract.1.4 The vales stated in inch-pound units are to be regardedas standard. The values given in parentheses are
6、 mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.5 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 a
7、nd health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 168 Terminology Relating to Thermal InsulationE 2234 Practice for Sampling a Stream of Product byAttributes Indexed by AQL3. Terminology3.1 Definitions:3.1.1 accep
8、table quality level (AQL)when a continuousseries of lots is considered, the quality level which for purposesof sampling inspection is the limit of a satisfactory processaverage. The listed AQL (AQL=10%) is the maximum percentdefective level accepted 95% of the time by the sampling plan.3.1.2 accepta
9、nce numberthe maximum number of thenonconformities or nonconforming units in the sample that willpermit acceptance of the inspected lot or batch.3.1.3 inspectionthe process of measuring, examining,testing, gaging, or otherwise comparing the unit with theapplicable requirements.3.1.4 inspection lota
10、collection of units of product fromwhich a sample is drawn and inspected to determine conform-ance with the acceptability criteria.3.1.4.1 DiscussionAn inspection lot may differ from a lotdefined for other purposes.3.1.5 inspection, normalinspection that is used in accor-dance with an acceptance sam
11、pling scheme when a process isconsidered to be operating at, or slightly better than, itsacceptable quality level.3.1.6 inspection, tighteneda feature of a sampling schemeusing stricter acceptance criteria than those used in normalinspection. Tightened inspection is used in some samplingschemes as a
12、 protective measure to increase the probability ofrejecting lots when experience shows the level of submittedquality has deteriorated significantly.3.1.6.1 DiscussionIt is expected that the higher rate ofrejections inherent with tightened inspection will lead thesupplier to improve the quality of th
13、e submitted product. Thecriteria for determining when quality has deteriorated signifi-cantly must be defined in objective terms for any givensampling scheme.3.1.7 lot (batch)a definite quantity of some productmanufactured under conditions of production that are consid-ered uniform.1This practice is
14、 under the jurisdiction of ASTM Committee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.31 on Chemical andPhysical Properties.Current edition approved April 15, 2008. Published May 2008. Originallyapproved in 1957. Last previous edition approved 2003 as C 390 03.2For
15、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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700,
16、 West Conshohocken, PA 19428-2959, United States.3.1.8 lot sizethe number of units in a lot or inspection lot.3.1.9 nonconforming unita unit of product or servicecontaining at least one nonconformity.3.1.10 nonconformitya departure of a quality characteris-tic from its intended level or state that o
17、ccurs with a severitysufficient to cause the product or service not to meet aspecification requirement.3.1.11 samplea group of units, portion of material, orobservations taken from the inspection lot that serves toprovide information that may be used as a basis for making adecision concerning the lo
18、t being inspected.3.1.12 sample sizethe number of units in a sample or thenumber of observations in a sample.3.1.13 unitan object on which a measurement or obser-vation may be made.3.2 Descriptions of Terms Specific to This Standard:3.2.1 lotan inspection lot as defined in 3.1.4.3.2.2 shipping packa
19、gethe smallest discrete package ofthermal insulation for purposes of shipping. Typically, ashipping package is one roll, bundle, bag, or carton of thermalinsulation.3.2.3 unita shipping package as described in 3.2.2.4. Significance and Use4.1 The sampling and inspection prescribed in this standardaf
20、ford the purchaser a practical level of quality assurance onincoming material. They are based on cost/risk relationshipsconsidered typical for preformed thermal insulations offeredfor general use. In all cases, the purchaser should review thisstandard and determine its suitability in terms of his sp
21、ecificneeds.4.2 This procedure is intended primarily for the inspectionof a continuing stream of lots, and there is not a highprobability of rejecting occasional off lots. Consumer protec-tion is based on economic pressure on the producer, throughgreater risk of lot rejection, to maintain the proces
22、s average at90 % conformance or better. Operating characteristic curvesfor the sampling plans employed can be found in PracticeE 2234, Table X-C through Table X-F.4.3 It is not the intent of this procedure to estimate lotquality, control the quality of production, relieve the supplier ofresponsibili
23、ty for the quality of material offered, or determinethe disposition of material found to be defective after receipt bythe purchaser.5. Classification of Requirements5.1 ASTM material specifications shall classify physicalrequirements in two categories:5.1.1 Qualification RequirementsThose requiremen
24、tswhich establish the general suitability of the product but are notjudged necessary, or practical, for routine inspection. Theserequirements usually relate to the inherent properties of thematerial, involve high inspection costs, require long-term tests,or are controlled indirectly by other require
25、ments.5.1.2 Inspection RequirementsThose requirements whichcan and should be monitored on a routine basis. Theserequirements are characterized by a high benefit/cost ratio.They may include visual and dimensional requirements, re-quirements for properties with potentially high variability, orrequirem
26、ents providing indirect control of performance char-acteristics.6. Acceptance for Qualification Requirements6.1 The suppliers certificate of compliance or a thirdpartys certificate of compliance shall be sufficient basis foracceptance of the lot for qualification requirements.6.1.1 The certificate s
27、hall state that compliance to thequalification requirements has been verified by actual inspec-tion of material manufactured within the past three years usingthe same basic ingredients and manufacturing process as thematerial offered.6.1.2 The supplier shall furnish an inspection report uponrequest.
28、7. Acceptance for Inspection Requirements7.1 The acceptance of a lot for inspection requirements shallbe based on the sampling plans and acceptance criteriaprescribed in Table 1 (preformed board, and preformed blockand pipe) and Table 2 (batts and blanket). Single Inspection andAQL = 10 % shall be u
29、sed.7.2 Sampling and inspection shall be carried out as de-scribed in Section 8. Test sample shall be randomly selectedfrom the lot.7.3 For preformed board, and preformed block and pipe lotsof 150 units or less, or batts and blanket lots of 16 146ft2(1500 m2) or less, not subject to tightened inspec
30、tion, thesuppliers certificate of compliance or a third partys certificateof compliance shall be sufficient basis for acceptance of the lotfor inspection requirements.TABLE 1 Sampling Plan and Acceptance Criteria for Inspection RequirementsA(Preformed Board, and Preformed Block and Pipe)Lot Size (Sh
31、ipping Units)Normal Inspection Tightened InspectionSample Size(Shipping Packages)Acceptance Number,Maximum Number ofNonconforming UnitsSample Size(Shipping Packages)AcceptanceNumber,Maximum NumberofNonconformingUnits150 or less see 7.3 see 7.3 51151 to 1200 5 1 8 11201 to 35 000 8 2 8 135 000 and ov
32、er 13 3 13 2AThe plan for normal inspection of lot sizes of 151 units and over, and the entire plan for tightened inspection are taken from Practice E 2234, using Special InspectionLevel S-2, AQL = 10 %.C3900827.3.1 The certificate shall state that compliance to inspec-tion requirements has been ver
33、ified by actual inspection ofmaterial of the same type, class, form, size, and thicknessmanufactured within the same production period as the mate-rial offered.7.3.2 The supplier shall furnish pertinent inspection recordsupon request.8. Procedure for Sampling and Inspection8.1 Establish the grouping
34、 of product to be considered thelot and determine the lot size:8.1.1 Unless otherwise specified in the material specifica-tion, order, or contract, the lot shall consist of all thermalinsulation of one type, class, form, size, and thickness pro-duced under the same conditions and procured at the sam
35、etime.8.1.2 The lot size shall be equal to the number of shippingpackages in the lot.8.2 Determine the required sample size from Table 1,expressed in terms of shipping units:8.2.1 Use normal inspection at the start of inspection and forany single lot.8.2.2 Shift from normal to tightened inspection w
36、hen two offive consecutive lots have been rejected.8.2.3 Shift from tightened to normal inspection after fiveconsecutive lots have been accepted.8.2.4 In the event that ten consecutive lots remain ontightened inspection, discontinue inspection under this stan-dard pending action to improve the quali
37、ty of submittedproduct.8.3 Select the sample from the lot:8.3.1 The sample shall consist of the number of shippingpackages determined as the sample size in 8.2.8.3.2 Select individual shipping packages from the entire lotat random and without regard to expected quality. Whenappropriate, select units
38、 from different sublots identified bysome rational criterion such as shipment or production group-ings.8.4 Perform the inspection called for in the ASTM materialspecification:8.4.1 From each shipping package in the sample, drawsufficient insulation material to perform the complete inspec-tion. This
39、may require a full shipping package or a portionthereof, as one or more pieces cut from a roll or one or moreboards or sections from a carton. Select the material at randomand without regard to quality.8.4.2 Inspect the insulation material drawn from each ship-ping package in the sample. Perform the
40、 number of determi-nations prescribed in the product specification or specified testmethods.8.5 Establish the number of nonconforming units in thesample:8.5.1 Compare the inspection results on the material drawnfrom each shipping unit to the requirements of the materialspecification.8.5.2 Classify t
41、he shipping unit as a nonconforming unit ifthe inspection results show one or more nonconformities to thematerial specification.8.6 Determine the acceptability of the lot:8.6.1 If the number of nonconforming units is equal to orless than the appropriate acceptance number in Table 1, acceptthe lot.8.
42、6.2 If the number of nonconforming units is greater thanthe acceptance number, reject the lot.9. Keywords9.1 batts; blanket; block; board; pipe; preformed; samplingand acceptance; thermal insulationTABLE 2 Sampling Plan and Acceptance Criteria for Inspection RequirementsA(Batts and Blankets)Lot Size
43、 (m2)BNormal Inspection Tightened InspectionSample Size(Shipping Packages)Acceptance Number,Maximum Number ofNonconforming UnitsSample Size(Shipping Packages)Acceptance Number,Maximum Number ofNonconforming Units1500 or less see 7.3 see 7.3 511501 to 2500 5 1 8 12501 to 5000 8 2 8 15001 to 9000 13 3
44、 13 29001 to 15 000 20 5 20 315 001 to 28 000 32 7 32 528 001 and over 50 10 50 8AThe plan for normal inspection of lot sizes of 1500 m2and over, and the entire plan for tightened inspection are taken from Practice E 2234, using Normal InspectionLevel II, AQL = 10 % and sample size based on 1080 ft2
45、(100 m2) per unit.BLot sizes for ft2are 16 146 or less, 16 417 to 26 911, 26 912 to 53 821, 53 822 to 96 878, 96 879 to 161 460, 161 461 to 301 399, and 301 400 and over.C390083ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item ment
46、ionedin 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 revision at any time by the responsible technical committee
47、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 comments will receive careful consideration at a meeting
48、 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 copyrighted by ASTM International, 100 Barr Harbor Drive, PO B
49、ox 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).C390084
