1、Designation: E 1548 09Standard Practice forPreparation of Aerospace Contamination Control Plans1This standard is issued under the fixed designation E 1548; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、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 is intended to assist in the preparation offormal plans for contamination control, especially of aerospacecritical surf
3、aces. Requirements may be established at thesystems level, either by the customer or the systems integrator,or at the subsystem level. Subsystem requirements may beimposed by the responsible subsystem supplier or they may beflowed down from the systems organization (4.7). The extentof detail and lev
4、el of cleanliness required can vary with theparticular application and type of hardware being built, but allaspects of contamination control must be included in a finalplan. Therefore, each of the following elements must beconsidered for inclusion in a contamination control plan(CCP):1.1.1 Cleanline
5、ss requirements for deliverable hardwareaddressing particulate, molecular, or biological contaminantsor combination thereof. Specify contamination limits and anybudget allocations.1.1.2 Implementation plans to achieve, verify, and maintainthe specified cleanliness requirements. Specify material andp
6、rocess controls, cleaning techniques, verification tests, pro-tection and prevention plans, transportation controls, andcorrective action for discrepancies.1.1.3 Environmental controls including clean facilities tobe used, facility maintenance, and monitoring schedule.1.1.4 Personnel and operational
7、 controls including operat-ing procedures, restrictions, training, motivation, and organi-zational responsibilities including the organization or indi-vidual for implementation and verification of the CCP.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement
8、are included in thisstandard.2. Referenced Documents2.1 ASTM Standards:2E 595 Test Method for Total Mass Loss and CollectedVolatile Condensable Materials from Outgassing in aVacuum EnvironmentE 1216 Practice for Sampling for Particulate Contaminationby Tape LiftE 1235 Test Method for Gravimetric Det
9、ermination of Non-volatile Residue (NVR) in Environmentally ControlledAreas for SpacecraftE 1549 Specification for ESD Controlled Garments Re-quired in Cleanrooms and Controlled Environments forSpacecraft for Non-Hazardous and Hazardous OperationsE 1559 Test Method for Contamination Outgassing Chara
10、c-teristics of Spacecraft MaterialsE 2042 Practice for Cleaning and Maintaining ControlledAreas and Clean RoomsE 2217 Practice for Design and Construction of AerospaceCleanrooms and Contamination Controlled AreasF50 Practice for Continuous Sizing and Counting of Air-borne Particles in Dust-Controlle
11、d Areas and Clean RoomsUsing Instruments Capable of Detecting Single Sub-Micrometre and Larger ParticlesF 303 Practices for Sampling for Particles in AerospaceFluids and ComponentsF 312 Test Methods for Microscopical Sizing and CountingParticles from Aerospace Fluids on Membrane Filters2.2 Governmen
12、t Standards:FED-STD-209E Airborne Particulate Cleanliness Classes inCleanrooms and Clean Zones3,41This practice is under the jurisdiction of ASTM Committee E21 on SpaceSimulation and Applications of Space Technology and is the direct responsibility ofSubcommittee E21.05 on Contamination.Current edit
13、ion approved April 1, 2009. Published April 2009. Originallyapproved in 1993. Last previous edition approved in 2003 as F 1548 03.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume informat
14、ion, refer to the standards Document Summary page onthe ASTM website.3Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.4FED-STD-209 has been superceded by ISO 14644-1 and -2. It may continue tobe used if mutually agreed
15、 to by customer and supplier.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.USAF Tech Order 00-25-203 Contamination Control ofAerospace Facilities, U.S. Air Force32.3 International Standards:5ISO 14644-1 Cleanrooms and Associated Co
16、ntrolled Envi-ronments, Classification of Air CleanlinessISO 14644-2 Cleanrooms and Associated ControlledEnvironmentsSpecifications for testing and monitoringto prove continued compliance with ISO 14644-1ISO 15388 Space SystemsContamination and CleanlinessControl2.4 IEST Standards:IEST-STD-CC1246D P
17、roduct Cleanliness Levels and Con-tamination Control Program6NOTE 1The Institute of Environmental Sciences has several Recom-mended Practices which may also be useful in the preparation of a CCP.3. Terminology3.1 Definitions:3.1.1 bidirectional reflectance distribution function(BRDF)the scattering p
18、roperties of light reflected off sur-faces, expressed as the ratio of differential outputs of radiancedivided by differential inputs of radiance. Surface contami-nants scatter the incident radiation in all directions and withvariable intensities; BRDF is a method to quantify the spatialdistribution
19、of the scattered energy.3.1.2 biological contaminationliving material such asalgae, bacteria, fungus, and so forth, which is capable ofreproducing, thus being an increasing contaminant source.3.1.3 budget allocationthe itemized summary of contami-nation accumulation for a given critical hardware ite
20、m distrib-uted over all phases from manufacture through end of perfor-mance lifetime.3.1.4 cleanrooman environmentally conditioned areawhere temperature, humidity, and airborne contaminants arecontrolled by design and operation. High Efficiency ParticulateAir (HEPA) filters or better are usually req
21、uired to achieve theair cleanliness level. Air particulate cleanliness is classified inaccordance with ISO 14644-1.3.1.4.1 as-built cleanrooma cleanroom that is completeand ready for operation, with all services connected andfunctional, but without equipment or operating personnel in thecleanroom.3.
22、1.4.2 at-rest cleanrooma cleanroom that is completeand ready for operation, with all services connected andfunctional, and with equipment installed and operable, asspecified but without operating personnel in the cleanroom.3.1.4.3 operational cleanrooma cleanroom in normal op-eration, with all servi
23、ces functioning and with equipment andpersonnel, if applicable, present and performing their normalwork functions in the cleanroom.NOTE 2For batch operations, specific conditions and requirementsshould be noted for monitoring and control.3.1.5 clean zonea defined space in which the concentra-tion of
24、 airborne particles is controlled to meet a specifiedairborne particulate cleanliness class.3.1.6 controlled areaan area which does not require ahigh degree of temperature and humidity control but a semi-clean atmosphere is desired. Air conditioning is standardcommercial design except that filtratio
25、n is rated to 80-85 % for1.0 micrometer (m) and larger particles to control airbornecontaminants. These areas shall not exceed the airborne par-ticle concentration of Class 8.5 (FED-STD-209E Class300,000) at 0.5 m and Class 8 (Class 100,000) at 5.0 m perISO 14644-1 (FED-STD-209E). Reference USAF Tec
26、h Order00-25-203.3.1.7 facilitythe total real property required to accomplishthe environmental control and operation of cleanrooms, cleanzones, and controlled areas as well as administrative andpersonnel support.NOTE 3This includes the cleanroom proper, air locks, change rooms,parts cleaning, storag
27、e, HVAC equipment, offices, and so forth.3.1.8 HVACHeating, Ventilating, and Air Conditioning.3.1.9 image analysisthe measurement of size, shape,number, position, orientation, brightness, and other parametersof small objects using the combination of an autofocusingmicroscope, an imaging sensor, and
28、a dedicated computersystem. Can be used to perform particle counts or measureparticle dimensions automatically, with far greater accuracythan manual techniques.3.1.10 molecular contaminationnonparticulate matter inthe form of droplets or thin films which adversely affectscomponent or system performa
29、nce.3.1.11 nonvolatile residue (NVR)soluble material remain-ing after evaporation of a filtered volatile fluid or precipitatefrom a gas phase, usually reported in milligrams per unit area(or volume).3.1.12 particulate contaminationsmall discrete mass ofsolid matter, usually measured in micrometers (
30、m), whichadversely affects component or system performance.3.1.13 precision cleaningcleaning of hardware surfacesby approved engineering methods to meet specific cleanlinesscriteria.3.1.14 visibly cleanabsence of particulate or molecularcontaminants when viewed from a specified distance withnormal (
31、or corrected to normal) vision with a specifiedillumination level.4. Contents of CCP4.1 General Items and Information:4.1.1 All CCPs shall include an introduction or scopespecifying the contamination-sensitive component(s) or sys-tem(s) being addressed, a list of applicable documents, and alist of d
32、efinitions including any acronyms and abbreviationsused in the document.4.1.2 The level of detail required and the nature and extentof controls needed depends upon a number of factors. Thesystems organization or systems integrator has a better over-view of contamination limitations, sensitivity of s
33、pecific com-ponents and hardware, and total mission requirements thansub-tier suppliers. Contamination limits for total systems are5Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.6Available from Institute of Environmental
34、 Sciences and Technology (IEST),Arlington Place One, 2340 S. Arlington Heights Rd., Suite 100, Arlington Heights,IL 60005-4516, http:/www.iest.org.E1548092the primary responsibility of the systems organization. Finalcontamination limits at delivery of the integrated system and atend of life should b
35、e established by agreement between thepurchaser and systems supplier. Each supplier is responsiblefor defining and controlling the contamination level of theparticular hardware being supplied, with the approval of thesystems organization, in addition to requirements levied by thesystems integrator.4
36、.1.3 The buyer and seller should agree on the contents andimplementation of the CCP before any parts are processedbeyond the first cleaning or inspection point. Suppliers ofsubsystems and components should prepare ContaminationControl Plans so that the functional requirements of thehardware are prot
37、ected. If a subsystem is particularly sensitiveto contamination, there must be adequate controls and compli-ance with system contamination requirements. Examples ofsensitive subsystems include optical or non-optical sensors,gyros, thermal control systems, liquid propellant systems, andcryogenic devi
38、ces.4.1.4 Some subsystems are relatively insensitive to con-tamination. These should be identified and justifications givenfor limited contamination control efforts. Even if a particularsubsystem or hardware is not sensitive to contamination it mustnot be a source of contamination for other, more se
39、nsitive orcritical hardware. Also it is important that system performanceor contamination allowables not be degraded by contaminantsemanating from contamination tolerant hardware.4.2 Cleanliness Requirements:4.2.1 Cleanliness requirements must be specified for deliv-erable components or systems addr
40、essing particulate, molecu-lar, or biological contaminants, or combination thereof. Pri-mary responsibility for contamination control remains with thehardware or subsystem supplier. Levels of control and allow-able types and quantities of contaminants shall be as agreed bythe supplier and systems or
41、ganization when applicable. Specifycontamination limits and the point in time when the require-ment must be verified (for example, IEST-STD-CC1246DLevel XXX after manufacture, or X.XX % area coverage atdelivery to integration contractor). Define any budget alloca-tions if different cleanliness level
42、s are to be verified at differenttime intervals. Also identify whether the requirement is criticalto the hardware performance or is necessary to protect othercritical hardware.4.2.2 Define how the cleanliness requirements will be im-posed in operation; identify the relevant documents such asdrawings
43、, process documents, inspection procedures, testplans, manufacturing flow diagrams, acceptance plans, and soforth.4.3 Implementation Plan:4.3.1 Attainment of Cleanliness RequirementsDescribethe means for achieving the specified cleanliness requirements.This focuses on (1) selection of low outgassing
44、, low shedding,and low particle generating raw materials, (2) design featuresto protect against contamination such as filters, cold traps,baffles, debris shields, and so forth, (3) cleaning and processingtechniques that will effectively remove contaminants fromsurfaces, and (4) facilities to be used
45、 for various operationssuch as cleanrooms of a specified class or controlled areas.Where pre-launch or post-launch cleaning operations areplanned, these shall be described here also. These elementsmay be contained in separate documents, but shall all beresponsive to the requirements and cross-refere
46、nced in theCCP. ISO 15388 also contains recommendations on contami-nation control requirements and guidelines for establishingcontamination control plans.4.3.2 Verification of Cleanliness RequirementsIdentifythe techniques planned to verify compliance with the cleanli-ness requirements, including pa
47、rticulate, molecular, or biologi-cal contaminants, or combination thereof. Rationale for use ofwitness samples versus direct examination or solvent extrac-tion techniques should be included. Specify method of directsampling, such as tape-lift per Practice E 1216, spray flush perPractices E 303, and
48、so forth, and specify method of testing,such as microscope counts per Test Methods F 312, outgassingper Test Method E 595, Test Method E 1559 to evaluateoutgassing materials characteristics and properties, black orwhite light visual examination, BRDF, and so forth. Specifymethodology for obtaining r
49、epresentative samples and methodof analysis for witness samples such as reflectance of mirrors,image analysis, direct quantitative measurement, black orwhite light visual examination, BRDF, and so forth. State thefrequency of sampling, whether sampling is directly on thehardware or via witness samples, and the justification for thesampling plan. Define the calibration of equipment used forcleanliness verification tests.4.3.3 Materials ControlDescribe the process for controland disposition of discrepant materials. Identify the documentswhich contain appr
