1、Designation: E2217 12Standard Practice forDesign and Construction of Aerospace Cleanrooms andContamination Controlled Areas1This standard is issued under the fixed designation E2217; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、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 The purpose of this practice is to provide design andconstruction guidelines for contamination controlled
3、facilitiesused in the assembly and integration of aerospace hardware.The guidelines herein are intended to ensure that the facilities,when used properly, will meet the cleanliness requirements ofaerospace hardware and processes. The objective is to limitcontamination due to the deposition of particu
4、late and molecu-lar contaminants on flight hardware surfaces.1.2 One cleanliness classification of a facility is the airborneparticle concentrations in accordance with ISO 14644-1 and14644-2. Airborne particle concentrations in accordance withFED-STD-209E are included for reference. This simple clas
5、-sification is inadequate to describe a facility that will supportthe assembly and integration of spacecraft. The extendedduration of hardware exposure during fabrication and testing,the sensitivity of the hardware to hydrocarbons and othermolecular contaminants, and the changing requirements during
6、assembly and integration must be considered in addition to theairborne particle concentrations.1.3 The guidelines specified herein are intended to providefacilities that will effectively restrict contaminants from enter-ing the facility, limit contamination generated by and withinthe facility, and c
7、ontinuously remove airborne contaminantsgenerated during normal operations. Some items of supporthardware, such as lifting equipment, stands, and shoe cleaners,are addressed since these items are often purchased andinstalled with the facility and may require accommodation inthe design of the facilit
8、y.1.4 Active filtration of molecular contaminants (such ashydrocarbons, silicones, and other chemicals) is discussed.Such active filtration of molecular contaminants may berequired for the processing of highly sensitive optical devices,especially infrared and cryogenic sensors. Control of micro-biol
9、ogical contamination is not included although HEPA (HighEfficiency Particulate Air) filtration will provide some controlof airborne bacteria, spores, and other viable contaminants thatare typically carried on particles of sizes 0.3 m and larger.Control of radioactive contamination and accommodation
10、ofvery hazardous materials such as propellants, strong acids orcaustics, or carcinogens are not addressed.1.5 No facility will compensate for excessive contaminationgenerated inside the facility. In addition to an effective facilitydesign, the user must also institute a routine maintenanceprogram (s
11、ee Practice E2042) for the facility, and personneland operational disciplines that limit the transfer of contami-nants through entry doors and contaminant generation insidethe facility.1.6 This practice only addresses guidelines for contamina-tion control in facility design. It must be implemented i
12、ncompliance with all mandatory government and regulatorybuilding and safety codes. References to related cleanroomstandards and U.S. building codes and standards may be foundin IEST-RP-CC012.1.7 The values stated in SI units are to be regarded asstandard. No other units of measurement are included i
13、n thisstandard.1.7.1 The values given in parentheses are provided forinformation only and are not considered standard.1.8 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-pria
14、te safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E595 Test Method for Total Mass Loss and CollectedVolatile Condensable Materials from Outgassing in aVacuum EnvironmentE1216 Practice for Sampling for Par
15、ticulate Contaminationby Tape LiftE1234 Practice for Handling, Transporting, and InstallingNonvolatile Residue (NVR) Sample Plates Used in Envi-ronmentally Controlled Areas for Spacecraft1This practice is under the jurisdiction of ASTM Committee E21 on SpaceSimulation and Applications of Space Techn
16、ology and is the direct responsibility ofSubcommittee E21.05 on Contamination.Current edition approved April 1, 2012. Published May 2012. Originallyapproved in 2002. Last previous edition approved in 2007 as E2217 - 02 (2007).DOI: 10.1520/E2217-12.2For referenced ASTM standards, visit the ASTM websi
17、te, 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, West Conshohocken, PA 19428-2959, United State
18、s.E1235 Test Method for Gravimetric Determination of Non-volatile Residue (NVR) in Environmentally ControlledAreas for SpacecraftE1548 Practice for Preparation ofAerospace ContaminationControl PlansE2042 Practice for Cleaning and Maintaining ControlledAreas and Clean RoomsE2088 Practice for Selectin
19、g, Preparing, Exposing, andAnalyzing Witness Surfaces for Measuring Particle Depo-sition in Cleanrooms and Associated Controlled Environ-mentsF24 Test Method for Measuring and Counting ParticulateContamination on SurfacesF25 Test Method for Sizing and Counting Airborne Particu-late Contamination in
20、Cleanrooms and Other Dust-Controlled AreasF50 Practice for Continuous Sizing and Counting of Air-borne Particles in Dust-Controlled Areas and Clean RoomsUsing Instruments Capable of Detecting Single Sub-Micrometre and Larger Particles2.2 ISO Standards:3ISO 14644-1 Cleanrooms and Associated Controlle
21、d Envi-ronments Part 1: Classification of Air CleanlinessISO 14644-2 Cleanrooms and Associated Controlled Envi-ronments Part 2: Specifications for Testing and Monitor-ing to Prove Continued Compliance with ISO 14644-1ISO 14644-3 Cleanrooms and Associated Controlled Envi-ronments Part 3: Test Methods
22、ISO 14644-4 Cleanrooms and Associated Controlled Envi-ronments Part 4: Design, Construction and Start-up2.3 Institute of Environmental Science and TechnologyStandards:IEST-RP-CC001 HEPA and ULPA Filters4IEST-RP-CC006 Testing Cleanrooms4IEST-RP-CC007 Testing ULPA Filters4IEST-RP-CC012 Considerations
23、in Cleanroom Design4IEST-RP-CC022 Electrostatic Charge in Cleanrooms andOther Controlled Environments4IEST-RP-CC034 HEPA and ULPA Filter Leak Tests4IEST-STD-CC1246 Product Cleanliness Levels and Con-tamination Control Program52.4 U.S Government Standards:FED-STD-209E Airborne Particulate Cleanliness
24、 Classes inCleanrooms and Clean Zones62.5 Other Publications:Procedural Standards for Certified Testing of Cleanrooms,National Environmental Balancing Bureau (NEBB)73. Terminology3.1 Definitions:3.1.1 aerosol, na gaseous suspension of fine solid orliquid particles.3.1.2 airfilters:3.1.2.1 HEPA (High
25、 Effciency Particulate Air) filter, naparticulate air filter having a minimum particle collectionefficiency of 99.97 % of particles greater than 0.3 m inaccordance with IEST-RP-CC001.3.1.2.2 ULPA (Ultra Low Penetration Air) filter, na par-ticulate air filter having a minimum particle collection effi
26、-ciency of 99.999 % of particles of sizes equal to and larger than0.12 m.3.1.2.3 prefilters, nair filters that are installed upstream ofthe HEPA or ULPA filters.3.1.2.4 DiscussionThese usually consist of rough filtersand medium efficiency filters that remove larger particles thanare removed by the H
27、EPA and ULPA filters; They are used toreduce the number of particles trapped on the high efficiencyfilters, thereby extending the lifetimes of the HEPA and ULPAfilters.3.1.3 airflow:3.1.3.1 unidirectional airflow, ncontrolled airflowthrough the entire cross-section of a cleanroom or clean zonewith a
28、 steady velocity and approximately equal streamlines.3.1.3.2 DiscussionThe airflow in a cleanroom may beeither vertical down-flow or horizontal with air leaving theroom either through nearly continuous floor or wall vents.Equipment and personnel in the room will cause air turbulence,but the airflow
29、is still considered unidirectional.3.1.3.3 nonunidirectional airflow, nair distribution wherethe supply air entering the cleanroom or clean zone mixes withthe internal air by means of induction.3.1.3.4 DiscussionAir typically enters through registersdistributed around the room above the working area
30、 and exitsthrough registers at floor level.3.1.3.5 mixed airflow, nair distribution in a cleanroom orclean zone in which the airflow is a mixture of both unidirec-tional and nonunidirectional.3.1.3.6 DiscussionDifferent locations in a cleanroom canhave different types of airflow. This is especially
31、true in largecleanrooms. A cleanroom design may include mixed airflow.3.1.4 changing room, nroom where people using a clean-room change into, or out of, cleanroom apparel.3.1.5 cleanroom, na specialized enclosed room employ-ing control over the airborne particle concentrations, tempera-ture, humidit
32、y, pressure, molecular contaminants, and opera-tions.3.1.5.1 cleanroom (alternate), na room in which theconcentration of airborne particles, temperature, humidity,pressure, molecular contaminants, and operations are con-trolled, and which is constructed and used in a manner tominimize the introducti
33、on, generation, and retention of con-taminants inside the room.3.1.6 cleanroom occupancy states:3Available from International Organization for Standardization (ISO), 1, ch. dela Voie-Creuse, CP 56, CH-1211 Geneva 20, Switzerland, http:/www.iso.org.4Available from Institute of Environmental Sciences
34、and Technology (IEST),Arlington Place One, 2340 S. Arlington Heights Rd., Suite 100, Arlington Heights,IL 60005-4516, http:/www.iest.org.5This replaces MIL-STD-1246C which is inactive.6This standard was cancelled 29 Nov. 2001 and is replaced by ISO 14644-1 andISO 14644-2. Copies of FED-STD-209E are
35、available from the Institute ofEnvironmental Sciences and Technology, 940 East Northwest Highway, MountProspect, IL 60036, and from U.S. government sources.7National Environmental Balancing Bureau, 8575 Grovemont Circle, Gaithers-burg, MD 20877-4121. http:/www.nebb.org/contact/.E2217 1223.1.6.1 as-b
36、uilt, adjcondition where the installation iscomplete with all services connected and functioning but withno equipment, flight hardware and materials, or personnelpresent.3.1.6.2 DiscussionFor contractual purposes, the partiesinvolved should have an agreement that defines this state.3.1.6.3 at-rest,
37、adjcondition where the installation iscomplete with equipment installed and operating in a manneragreed upon by the customer and supplier, but with nopersonnel present.3.1.6.4 operational, adjcondition where the installation isfunctioning in the specified manner, with the specified numberof personne
38、l present and working in the agreed upon manner.3.1.7 clean zone, ndedicated space in which the concen-tration of airborne particles is controlled, which is constructedand used in a manner to minimize the introduction, generation,and retention of particles inside the zone, and in which otherrelevant
39、 parameters, for example, temperature, humidity, pres-sure, and molecular contaminants, are controlled as necessary.3.1.8 contaminant, nany particulate, molecular, non-particulate, and biological entity that can adversely affect theproduct or process.3.1.9 contaminant deposition, nparticulate and mo
40、lecularcontaminants that form on surfaces resulting from processessuch as fallout, condensation, electrostatic attraction, and othermechanisms.3.1.10 contamination controlled area, na specialized en-closed facility employing control over the particulate matter inair, temperature, and humidity that m
41、ay not meet the require-ments of ISO 14644-1 or FED-STD-209E because of no HEPAor ULPA type filters.3.1.10.1 DiscussionFor example, without a final stage ofHEPAor ULPAfilters, the airborne particle concentrations mayonly meet ISO Class 8.5 (FS209E Class 300 000) for particlesequal to and greater tha
42、n 0.3 m but may meet ISO Class 8(FS209E Class 100 000) for particles equal to and greater than5 m.3.1.11 electrostatic discharge (ESD), nthe rapid, sponta-neous transfer of electrostatic charge induced by a highelectrostatic field.3.1.11.1 DiscussionUsually, the charge flows through aspark between t
43、wo bodies at different electrostatic potentials asthey approach one another.3.1.12 electromagnetic interference (EMI), ninterference,generally at radio frequencies, that is generated inside systems,as contrasted to radio-frequency interference coming fromsources outside a system.3.1.13 facility (cle
44、an facility), nthe total real propertyrequired to accomplish the cleanroom functions.3.1.13.1 DiscussionThis includes all the buildings, clean-rooms, offices, laboratories, storage areas, HVAC equipment,and other support areas for operations and personnel.3.1.14 gas phase adsorber cell, na modular c
45、ontainer foran adsorbent to trap contaminant gases from air and other gasesused in processing.3.1.15 installation, ncleanroom or one or more cleanzones, together with all associated structures, air-treatmentsystems, services, and utilities.3.1.16 macroparticle, na particle with an equivalent di-amet
46、er greater than 5 m.3.1.16.1 DiscussionThe M descriptor defines the mea-sured or specified concentrations of macroparticles per cubicmeter of air. This is defined in ISO 14644-1.3.1.17 monitoring, nobservations made by measurementin accordance with a defined method and plan to provideevidence of the
47、 performance of an installation.3.1.18 nonvolatile residue (NVR), ncontaminant residuewithout distinct dimensions. It typically consists of hydrocar-bons, silicones, and other higher molecular weight speciesdeposited through condensation, direct contact transmission(that is, fingerprints) or as resi
48、due remaining after evaporationof a liquid.3.1.19 outgassing, nthe evolution of gas from a material,usually in a vacuum. Outgassing also occurs in a higherpressure environment.3.1.19.1 DiscussionWhile outgassing is typically consid-ered a vacuum phenomenon, some materials, such as polyvinylchloride,
49、 contain volatile components, such as plasticizers, thatwill diffuse from bulk materials and evaporate under standardtemperatures and pressures. These volatile components arehighly contaminating to sensitive aerospace hardware.3.1.20 particle fallout, nparticulate matter that accumu-lates on surfaces due to gravity settling. This matter is often ofa particulate size larger than that measured by airborne particlecounters.3.1.21 radio-frequency interference (RFI), ninterferencefrom sources of energy outside a system or systems, ascontraste
