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BS EN 16603-35-06:2014 BSI Standards Publication Space engineering — Cleanliness requirements for spacecraft propulsion hardware BS EN 16603-35-06:2014 BRITISH STANDARD National foreword This British Standard is the UK implementation of EN 16603-35-06:2014 The UK participation in its preparation was entrusted to Technical Committee ACE/68, Space systems and operations A list of organizations represented on this committee can be obtained on request to its secretary This publication does not purport to include all the necessary provisions of a contract Users are responsible for its correct application © The British Standards Institution 2014 Published by BSI Standards Limited 2014 ISBN 978 580 84094 ICS 49.140 Compliance with a British Standard cannot confer immunity from legal obligations This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 September 2014 Amendments issued since publication Date Text affected BS EN 16603-35-06:2014 EN 16603-35-06 EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM September 2014 ICS 49.140 English version Space engineering - Cleanliness requirements for spacecraft propulsion hardware Ingénierie spatiale - Exigences de propreté des éléments de propulsion des véhicules spatiaux Raumfahrttechnik - Sauberkeitsanforderungen für die Antriebstechnik von Raumfahrtzeugen This European Standard was approved by CEN on March 2014 CEN and CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN and CENELEC member This European Standard exists in three official versions (English, French, German) A version in any other language made by translation under the responsibility of a CEN and CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels © 2014 CEN/CENELEC All rights of exploitation in any form and by any means reserved worldwide for CEN national Members and for CENELEC Members Ref No EN 16603-35-06:2014 E BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Table of contents Foreword Scope Normative references Terms, definitions and abbreviated terms 10 3.1 Terms from other standards 10 3.2 Terms specific to the present standard 10 3.3 Abbreviated terms 13 3.4 Symbols 13 Cleanliness requirements 14 4.1 General 14 4.2 Design requirements .15 4.3 4.4 4.5 4.2.1 General .15 4.2.2 Components 15 4.2.3 System 17 4.2.4 Ground support equipment (GSE) 17 Manufacturing 18 4.3.1 General .18 4.3.2 Manufacturing processes 18 4.3.3 Machined parts 18 4.3.4 Tubing and manifolds 18 4.3.5 Components 20 4.3.6 Subsystems and systems 21 4.3.7 Final rinsing solutions 21 Cleanliness classes definition 22 4.4.1 Particulate 22 4.4.2 Non-volatile residues (NVR) 25 4.4.3 Dryness and liquid residuals 25 4.4.4 Requirements on process fluids to meet cleanliness classes 26 Test methods 27 BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) 4.6 Code usage 27 Cleaning techniques 28 5.1 General 28 5.2 Environment, health and safety .29 5.3 5.4 5.5 5.6 5.2.1 General .29 5.2.2 Hardware configuration requirements 29 5.2.3 Cleaning process approval 30 Pre-cleaning 30 5.3.1 General .30 5.3.2 Mechanical pre-cleaning 30 5.3.3 Chemical pre-cleaning 31 Precision cleaning 32 5.4.1 General .32 5.4.2 Re-cleaning operational systems 32 Drying methods 33 5.5.1 General .33 5.5.2 Gaseous purge-drying .33 5.5.3 Drying sample 34 5.5.4 Flow rates during purging 35 5.5.5 Vacuum drying procedure 35 Excepted components, subsystems and systems 36 Cleanliness verification requirements 37 6.1 6.2 6.3 Surface 37 6.1.1 Visual and UV inspection 37 6.1.2 pH-test 37 Acceptance inspection of items cleaned in a controlled environment 38 6.2.1 General .38 6.2.2 Test fluids 38 6.2.3 Test fluid volume for analysis 39 6.2.4 Analysis of test fluid-flush sample (solvent) 39 6.2.5 Analysis of aqueous-based, liquid-flush sample 40 6.2.6 Drying .41 6.2.7 Vacuum drying 41 Maintaining cleanliness 42 6.3.1 Pressurant gas purge 42 6.3.2 Installation and marking of temporary hardware 42 6.3.3 Temporary hardware replacement 42 BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) 6.3.4 6.4 Component replacement 43 Dryness verification 43 6.4.1 General .43 6.4.2 Purge dryness 43 6.4.3 Vacuum dryness .43 6.4.4 Sample test and qualified procedure 44 Acceptance inspection of packaging materials 45 7.1 Environmental control .45 7.2 Sampling 45 7.3 Thickness of packaging film 45 7.4 Static electricity .46 7.5 Verification of cleanliness level 46 7.5.1 General .46 7.5.2 Minimum surface area for test 46 7.5.3 Sample preparation 46 7.5.4 Rinsing procedures 47 Packaging and protection 48 8.1 Approved coverings 48 8.2 Packaging operations .48 8.3 Certification labels 49 Deliverables 50 10 Test procedures 51 10.1 Test liquid-flush procedure (solvent) 51 10.2 Gas flow test procedure 51 11 Sampling and analytical practices 52 11.1 Cleanliness level test methods 52 11.1.1 General .52 11.1.2 Method I “Liquid Flush Test” 52 11.1.3 Method II “Liquid Flow Test” 53 11.1.4 Method III “Gas Flow Test” 53 11.1.5 Method IV “Liquid flow test under operating conditions” 53 12 Determination of particle population and NVR analysis 55 12.1 Microscopic particle population .55 12.2 Gravimetric NVR analysis method 56 BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Annex A (normative) Cleanliness Requirements Analysis (CRA) for spacecraft propulsion components, subsystems and systems - DRD 57 Annex B (normative) Cleaning Technique Selection (CTS) for spacecraft propulsion components, subsystems and systems - DRD 59 Annex C (normative) Cleanliness Certificate (CC) for spacecraft propulsion components, subsystems and systems - DRD 61 Annex D (normative) Typical test and cleaning liquids 64 Annex E (informative) Pre-cleaning sequences 67 Annex F (informative) Cleanliness certificate 69 Bibliography 71 Figures Figure F-1 : Example of a cleanliness certificate 70 Tables Table 4-1: Cleanliness classes .24 Table 4-2: NVR contamination levels 25 Table 4-3: Visible contamination levels 27 Table 7-1: Packaging materials 46 Table E-1 : Typical pre-cleaning sequence for common materials 67 BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Foreword This document (EN 16603-35-06:2014) has been prepared by Technical Committee CEN/CLC/TC “Space”, the secretariat of which is held by DIN This standard (EN 16603-35-06:2014) originates from ECSS-E-ST-35-06C rev.1 This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by March 2015, and conflicting national standards shall be withdrawn at the latest by March 2015 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association This document has been developed to cover specifically space systems and has therefore precedence over any EN covering the same scope but with a wider domain of applicability (e.g : aerospace) According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Scope ECSS-E-ST-35-06 belongs to the Propulsion field of the mechanical discipline, and concerns itself with the cleanliness of propulsion components, sub-systems and systems The standard • defines design requirements which allow for cleaning of propulsion components sub-systems and systems and which avoid generation or unwanted collection of contamination, • identifies cleanliness requirements (e.g which particle / impurity / wetness level can be tolerated), • defines requirements on cleaning to comply with the cleanliness level requirements, and the requirements on verification, • identifies the cleanliness approach, cleaning requirements, (e.g what needs to be done to ensure the tolerable level is not exceeded, compatibility requirements), • identifies, specifies and defines the requirements regarding conditions under which cleaning or cleanliness verification takes place (e.g compatibility, check after environmental test) The standard is applicable to the most commonly used propulsion systems and their related storable propellant combinations: Hydrazine (N2H4), Mono Methyl Hydrazine (CH3N2H3), MON (Mixed Oxides of Nitrogen), Nitrogen (N2), Helium (He), Propane (C3H8), Butane (C4H10) and Xenon (Xe) This standard is the basis for the European spacecraft and spacecraft propulsion industry to define, achieve and verify the required cleanliness levels in spacecraft propulsion systems This standard is particularly applicable to spacecraft propulsion as used for satellites and (manned) spacecraft and any of such projects including its ground support equipment External cleanliness requirements, e.g outside of tanks, piping and aspects such as fungus and outgassing are covered by ECSS-Q-ST-70-01 This standard may be tailored for the specific characteristic and constraints of a space project in conformance with ECSS-S-ST-00 BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this ECSS Standard For dated references, subsequent amendments to, or revisions of any of these publications, not apply However, parties to agreements based on this ECSS Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below For undated references the latest edition of the publication referred to applies EN reference Reference in text Title EN 16601-00-01 ECSS-S-ST-00-01 ECSS system — Glossary of terms EN 16603-35 ECSS-E-ST-35 Space engineering — Propulsion general requirements EN 16602-40 ECSS-Q-ST-40 Space product assurance — Safety EN 16602-70-01 ECSS-Q-ST-70-01 Space product assurance — Cleanliness and contamination control EN 16602-70 ECSS-Q-ST-70 Space product assurance — Materials, mechanical parts and processes ISO 2210:1972 Liquid halogenated hydrocarbons for industrial useDetermination of residue on evaporation ISO 5789:1979 Fluorinated hydrocarbons for industrial use — Determination of non-volatile residue ISO 5884:1978 Aerospace — Fluid systems and components — Methods for system sampling and measuring the solid particle contamination of hydraulic fluids ISO 14951-3:2000 Space systems —Fluid characteristics —Part 3: Nitrogen ISO 14951-4:2000 Space systems — Fluid characteristics —Part 4: Helium ISO 14951-10:2000 Space systems — Fluid characteristics —Part 10: Water ISO 14952-3:2003 Space systems — Surface cleanliness of fluid systems — Part 3: Analytical procedures for the determination of non-volatile residues and particulate contamination BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Terms, Definitions, Abbreviated terms and Symbols a The CTS shall use the terms, definitions, abbreviated terms and symbols used in ECSS-S-ST-00-01 and ECSS-E-ST-35 b The CTS shall include any additional term, definitions, abbreviated terms and symbol used Cleaning Techniques selection assessment a The selected cleaning techniques for the propulsion hardware shall be reported in conjunction with assembly, integration, transport, test, storage and mission b The justification of the selection shall be given, taking into account: c The cleanliness requirements defined in the CRA in conformance with Annex A The analysis of the component, subsystem or system design and related GSE and configuration for the feasibility of cleaning, drying and verification testing The cleaning materials including their specification, chemical and physical properties to assess compatibility with the hardware to be cleaned The cleaning equipment and processes to assess compliance with the hardware to be cleaned and certified in conformance with Annex C The selected cleaning materials, equipment and process conditions shall be listed a Utilization of results The processes and related procedures for cleaning and cleanliness verification shall be described B.2.2 None 60 Special remarks BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Annex C (normative) Cleanliness Certificate (CC) for spacecraft propulsion components, subsystems and systems - DRD C.1 DRD Identification C.1.1 Requirement identification and source document This DRD is called from ECSS-E-ST-35-06, requirements 4.1k; 4.4.1b; 4.4.2b; 4.4.3a; 4.6a; 6.1.1h; 6.1.2c; 6.4.1a and9a.3 C.1.2 Purpose and objective The cleanliness certificate provides evidence that the subject meets the cleanliness requirements, reports the test results and identifies the responsible authority NOTE C.2 An example of certificate ECSS-E-ST-35-06 Annex F is given in Expected response C.2.1 NOTE a Scope and content The CC is a form sheet This DRD does not specify the format, presentation or delivery requirements for the certificate An example format is shown in ECSS-E-ST-35-06 Annex D Identification header The identification header shall contain: Name of the cleaning responsible company, institution or organization Order number Name of supplier or customer 61 BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Name of hardware Name of project Configuration number of hardware (CI Nr.) Part number (P Nr.) Serial number (S Nr.) a Visual inspection results The visual inspection results part shall contain: Check box for requirement application Identification of procedure used Specification of requirement: a 62 Specific visual inspection requirement (GC) regarding manufacturing (e.g burrs removed, surface finish applied) (b) Visually clean (VC) (c) Ultraviolet light (VC+UV) Date of tests Particulate contamination results The particulate contamination results part shall contain: Identification of procedure used Definition of fluids used during test Check boxes for particulate matter requirements application Specification of cleanliness requirement(s) in conformance with clause 4.5 for particulate matter Specification of specific cleanliness requirements (e.g no metallic particles above 50 µm) Space for the record of the actual particle count results (e.g print out from automatic counter) Date of tests a (a) Non-volatile residue results (NVR) The non-volatile residue results (NVR) part shall contain: Identification of procedure used Definition of fluids used during test Check boxes for NVR requirements application Boxes for NVR results Date of tests BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) a pH test results The pH test results part shall contain: Check box for requirement application Identification of procedure used Definition of success criterion Record of test result Date of tests a Dryness results The dryness results part shall contain: Check box for requirement application Identification of procedure used Specification of gases used Liquid removed Definition of success criterion Record of test result Date of tests a Signatures The cleanliness certificate shall be dated, signed by the responsible operator and by the representative of the quality and product assurance authority C.2.2 Special remarks None 63 EN 16603-35-06:2014 (E) Annex D (normative) Typical test and cleaning liquids Table A-1 : Typical test and cleaning fluids Test liquid Remarks Water (H2O) Specifications Alternative names ISO 14951-10 Perfluoro-n-butyl methyl ether (C4F9OCH3) HFE 7100 (3M-NOVEC) Tetrachloroethylene (C2Cl4) This solvent has a threshold ASTM D4376 limit value and may pose a hazard in controlled areas or clean rooms Perchloroethylene, tetrachloroethene, ethylene tetrachloride, 1,1,2,2tetrachloroethylene, perc ("perk"), perchlor, carbon dichloride Isopropanol ((CH3)2CHOH) This solvent is not recommended for oxidiser ASTM D770-05 2-propanol, Isopropyl alcohol, Propan-2-ol Methanol (CH3OH) This solvent is not recommended for oxidiser ASTM D1152 methyl alcohol Ethanol (C2H5OH) This solvent is not recommended for oxidiser O-E-760D ethyl alcohol Acetone (CH3)2CO This solvent is not recommended for oxidiser ASTM D329 Propanone, β-ketopropane, Dimethyl ketone 64 Commercially known as EN 16603-35-06:2014 (E) Test liquid Remarks Specifications Alternative names Commercially known as Azeotrope of C3H2F10 (62 % by mass ) and C2H2Cl2 (38 % by mass) This solvent has a threshold SEMI C47-0699 limit value and may pose a hazard in controlled areas or clean rooms C3Cl2HF5 This solvent has a threshold limit value and may pose a hazard in controlled areas or clean rooms HCFC - 225 ca/cb (3M-NOVEC); The ca/cb ratio is 45/55 C2Cl2H3F This solvent has a threshold limit value and may pose a hazard in controlled areas or clean rooms HCFC-141b (3M-NOVEC) C5H2F10 This solvent has a threshold limit value and may pose a hazard in controlled areas or clean rooms Azeotropic ,mixture of This solvent has a threshold C5H3F9O and C2H2Cl2 limit value and may pose a hazard in controlled areas or clean rooms Azeotropic mixture of C10H22, C11H24, C12H26 not recommended for oxidiser C2H2Cl2 known as (E)-1,2dichloroethene, trans-1,2dichloroethene, trans-acetylene dichloride, 1,2-trans-dichloroethylene, 1,2-trans-dichloroethene 3M Material safety data sheet HFE-7100 3M (TM) Novec (TM) Engineered Fluid 04/09/2004 HFC 4310 MEE (3M-NOVEC) C5H3F9O known as 1,1,1,2,2,3,3,4,4Nonafluoro-4-methoxybutane, Nonafluorobutyl methyl ether, 1-Methoxynonafluorobutane HFE 71DE (3M-NOVEC) A mixture of methyl nonafluorobutyl ether (20% 80%) and methylnonafluoroisobutyl ether (20% - 80%) Castrol Techniclean AS58 65 EN 16603-35-06:2014 (E) Test liquid MEK (CH3COCH2CH3) Remarks not recommended for oxidiser Specifications ASTM D740 Alternative names Commercially known as Ethylmethylketone, 2-Butanon, Methylaceton, Methylethylketone This solvent has a threshold limit value and may pose a hazard in controlled areas or clean rooms Alkaline based cleanser contains water, glycol ether, phosphates, tensides Henkel TURCO 3878 Alkaline based cleanser contains NaOH, alkalis, salts AMS 1379, 1380; of organic acids, tensides Henkel TURCO 4181 Alkaline based cleanser contains borates, phosphates, tensides Henkel TURCO 4215 66 BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Annex E (informative) Pre-cleaning sequences Weld scale, corrosion, or heat oxidation Copper, brass, bronze Stainless steel Water rinse High-purity water Drying × × × × × × × × × × × Bare or machined, free of heat oxidation × × × × × Conversion or chemical film coating × × × × Weld scale, corrosion, or heat oxidation × × × × × × Free of scale × × × × × × × × × × × × × × × × × × × × × × × × × × × × × Weld scale, corrosion, or heat oxidation × × Passivated × Water rinse Conversion or chemical film coating Acid pickle × Water rinse × Detergent clean Bare or machined, free of heat oxidation Surface condition Water rinse Alkaline clean Aluminium Degrease Material Mechanical descale / cleaning Table E-1: Typical pre-cleaning sequence for common materials × Free of scale × × × × Carbon steel Weld scale, corrosion, or heat oxidation × × × × × × Titanium Bare or machined × ×a × × × × 67 Electroplated parts and dissimilar metals As received × × × × × × × × × × × × Water rinse Water rinse × Passivated Acid pickle Water rinse × Detergent clean × Drying As received × High-purity water Non-metallic parts Water rinse Conversion or chemical film coating Alkaline clean Surface condition Degrease Material Mechanical descale / cleaning BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) NOTE Symbols in the block denote a process for the surface condition indicated, and steps are normally accomplished in consecutive order from left to right a Do not use halogenated solvents 68 BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Annex F (informative) Cleanliness certificate Figure F-1 provides an example form that can be used as cleanliness certificate 69 BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Figure F-1: Example of a cleanliness certificate 70 BS EN 16603-35-06:2014 EN 16603-35-06:2014 (E) Bibliography EN reference Reference in text Title EN 16601-00 ECSS-S-ST-00 ECSS system — Description, implementation and general requirements EN 16601-35-10 ECSS-E-ST-35-10 Space engineering — Compatibility testing for liquid propulsion systems MIL-STD-1246C, 11 April 1994 Military Standard Product Cleanliness Levels and Contamination Control Program, “Metric” MIL-STD-1774, April 1982 Military Standard Process for Cleaning Hydrazine Systems and Components FS504574 Rev C, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, 28 May 1974 General Cleaning Requirements for Spacecraft Propulsion Systems and Support Equipment, Manufacturing Process Specification 71 This page deliberately left blank This page deliberately left blank NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW British Standards Institution (BSI) BSI is the national body responsible for preparing British Standards and other standards-related publications, information and services BSI is incorporated by Royal Charter British Standards and other standardization products are published by BSI Standards Limited About us Revisions We bring together business, industry, government, consumers, innovators and others to shape their combined experience and expertise into 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