Space product assurance - Corrosion

The purpose of the proposed Standard is to summarise the (general) corrosion protection requirements applicable to the materials, surface treatments, finishing and manufacturing processes used for space flight hardware.
It contains the minimum requirements necessary to guarantee and verify the suitability of materials, coatings systems and processes for corrosion control of space rated products.
The Standard classifies the corrosion environments and requires the issuing of a Corrosion Prevention and Control Plan based on the identified environmental classes. Testing and acceptance criteria are specified for each environmental class.
The scope of the document would include all flight parts and components used for space missions including Ground Support Equipment (GSE), where the materials and processes used in interfacing ground support equipment, test equipment, hardware processing equipment, hardware packaging and hardware shipment are to be controlled in order to prevent damage to or contamination of flight hardware.

Raumfahrtproduktsicherung - Korrosion

Assurance produit des projets spatiaux - Corrosion

Le présent document spécifie les exigences minimales pour qualifier les matériaux et procédés sélectionnés afin d'obtenir une protection contre la corrosion. Des essais supplémentaires peuvent être réalisés pour satisfaire aux exigences relatives aux matériaux et procédés utilisés pour des applications de vol spécifiques.
La présente norme spécifie le comportement des métaux et alliages mais n'ôte pas la responsabilité concernant la dégradation des autres matériaux à considérer.
Le présent document ne couvre par les exigences relatives à la protection contre la fissuration par corrosion sous contrainte, traitées par une norme dédiée, l’ECSS-Q-ST-70-36.
La présente norme peut être adaptée aux caractéristiques et contraintes spécifiques d'un projet spatial, conformément à l'ECSS-S-ST-00.

Zagotavljanje varnih proizvodov v vesoljski tehniki - Korozija

Namen predlaganega standarda je povzeti (splošne) zahteve za zaščito pred korozijo, ki se uporabljajo za materiale, površinsko obdelavo, končno obdelavo in proizvodne procese, ki se uporabljajo za strojno opremo v vesoljskih poletih. Vsebuje minimalne zahteve, ki so potrebne za zagotovitev in preverjanje primernosti materialov, premaznih sistemov in procesov za nadzor korozije vesoljskih izdelkov. Standard razvršča korozijska okolja in zahteva izdajo načrta za preprečevanje in nadzor korozije, ki temelji na opredeljenih okoljskih razredih. Za vsak okoljski razred so določeni kriteriji preskušanja in sprejemljivosti. Področje uporabe dokumenta vključuje vse dele za letenje in komponente, ki se uporabljajo za vesoljske misije, vključno s podporno opremo na tleh (GSE), kjer se materiali in procesi, ki se uporabljajo pri povezovanju podporne opreme na tleh, preskusne opreme, opreme za obdelavo strojne opreme, embalaže strojne opreme in pošiljanja strojne opreme nadzorujejo, da se prepreči poškodovanje ali kontaminacija letalske strojne opreme.

General Information

Status
Published
Public Enquiry End Date
29-Jun-2016
Publication Date
07-Jan-2019
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
03-Jan-2019
Due Date
10-Mar-2019
Completion Date
08-Jan-2019

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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Zagotavljanje varnih proizvodov v vesoljski tehniki - KorozijaRaumfahrtproduktsicherung - KorrosionAssurance produit des projets spatiaux - CorrosionSpace product assurance - Corrosion49.140Vesoljski sistemi in operacijeSpace systems and operations49.040Prevleke in z njimi povezani postopki, ki se uporabljajo v letalski in vesoljski industrijiCoatings and related processes used in aerospace industryICS:Ta slovenski standard je istoveten z:EN 16602-70-14:2018SIST EN 16602-70-14:2019en,fr,de01-marec-2019SIST EN 16602-70-14:2019SLOVENSKI
STANDARD



SIST EN 16602-70-14:2019



EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 16602-70-14
December
t r s z ICS
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v {ä s v r
English version
Space product assurance æ Corrosion
Assurance produit des projets spatiaux æ Corrosion
Raumfahrtproduktsicherung æ Korrosion This European Standard was approved by CEN on
s t October
t r s zä
C Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alterationä Upætoædate lists and bibliographical references concerning such national standards may be obtained on application to the CENæCENELEC Management Centre or to any CEN and CENELEC memberä
translation under the responsibility of a CEN and CENELEC member into its own language and notified to the CENæCENELEC Management Centre has the same status as the official versionsä
CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austriaá Belgiumá Bulgariaá Croatiaá Cyprusá Czech Republicá Denmarká Estoniaá Finlandá Former Yugoslav Republic of Macedoniaá Franceá Germanyá Greeceá Hungaryá Icelandá Irelandá Italyá Latviaá Lithuaniaá Luxembourgá Maltaá Netherlandsá Norwayá Polandá Portugalá Romaniaá Serbiaá Slovakiaá Sloveniaá Spainá Swedená Switzerlandá Turkey and United Kingdomä
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels y any means reserved worldwide for CEN national Members and for CENELEC Membersä Refä Noä EN
s x x r tæ y ræ s vã t r s z ESIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 2 Table of contents European Foreword . 5 Introduction . 6 1 Scope . 7 2 Normative references . 8 3 Terms, definitions and abbreviated terms . 9 3.1 Terms from other standards . 9 3.2 Terms specific to the present standard . 9 3.3 Abbreviated terms. 10 3.4 Nomenclature . 11 4 Principles . 12 4.1 General . 12 4.2 Eight forms of corrosion . 12 4.3 Corrosion protection . 13 5 Requirements . 14 5.1 Classification of corrosive environments . 14 5.2 Performance requirements . 15 5.3 Test samples definition . 16 5.4 Test methods . 16
Overview . 16
Class 1: Seawater Immersion . 18
Class 2: Seacoast, Outdoor . 18
Class 3: Inland, Outdoor . 18
Class 4: Chemical or Microbial-Induced Corrosion . 18
Class 5: Indoor, Uncontrolled . 18
Class 6: Indoor, Controlled . 18 5.5 Corrosion protection . 19
Process verification . 19
Cleaning and surface preparation . 19 5.6 Metallic finishes . 20 SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 3
Verification of metallic finishes . 20
Nickel plating . 20
Chromium plating . 21
Zinc-Nickel plating . 21
Copper plating . 22
Silver plating . 22
Tin plating . 22
Gold plating . 22
Vapour deposited coatings (CVD and PVD) . 22 5.7 Inorganic finishes . 23
Verification of inorganic finishes . 23
Anodic oxidations on aluminium and its alloys and titanium and its alloys. 23 5.8 Organic finishes . 23 5.9 Design considerations for corrosion control . 24
Surface treatments processes . 24
Cut edges . 24
Drainage and airflow . 24
Galvanic compatibility . 24 Annex A (informative) Corrosion . 25 A.1 Overview . 25 A.2 The eight forms of corrosion . 25 A.2.1 General corrosion . 25 A.2.2 Galvanic corrosion . 25 A.2.3 Crevice corrosion . 26 A.2.4 Pitting . 26 A.2.5 Intergranular corrosion . 27 A.2.6 Dealloying or Selective leaching . 27 A.2.7 Erosion corrosion . 27 A.2.8 Stress corrosion . 27 A.3 Hydrogen damage . 28 A.4 Corrosion in clean rooms . 28 Annex B (informative) Tape test method . 29 Annex C (informative) Damp heat test method . 30 C.1 Introduction . 30 C.2 Significance and use . 30 C.3 Apparatus and test specimens . 30 SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 4 C.3.1 Test chambers . 30 C.3.2 Test specimens . 30 C.4 Position of test specimens during exposure . 31 C.5 Conditions in the chamber . 31 C.6 Procedure . 31 C.7 Evaluations of results . 31 C.8 Records and report . 32 Bibliography . 33
Figures
: Tape test method . 29
Tables Table 5-1: Definition of corrosive environment classes . 15 Table 5-2– Matrix of test methods versus environments . 17
SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 5 European Foreword This document (EN 16602-70-14:2018) has been prepared by Technical Committee CEN-CENELEC/TC 5 “Space”, the secretariat of which is held by DIN. This standard (EN 16602-70-14:2018) originates from ECSS-Q-ST-70-14C. 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 June 2019, and conflicting national standards shall be withdrawn at the latest by June 2019. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identifying any or all such patent rights. This document has been prepared under a standardization request 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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 6 Introduction This standard is aimed primarily at flight hardware including launchers but the principles can also be applied to ground support equipment. Materials and processes used in ground support equipment, test equipment, hardware processing equipment, hardware packaging, hardware shipment and interfacing with flight hardware are to be controlled to prevent damage to or contamination of flight hardware. This standard describes the requirements necessary to show that hardware is adequately protected from corrosion. The purpose of this document is to: • assess the risk of each form of corrosion, • describe the corrosion protection requirements needed to mitigate the risks of corrosion, and • define the acceptance criteria for the protected metal or alloy system that shows fitness for purpose over the life of the mission. SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 7 1 Scope This document specifies the minimum requirements to qualify the materials and processes selected to provide corrosion protection. Additional testing can be performed to satisfy the requirements for materials and processes used in specific flight applications. This standard specifies the behaviour of metals and alloys but it does not remove the responsibility for the degradation of other materials such as polymers or ceramics to be considered. This standard refers only to metallic materials. This document does not cover the requirements for protection against stress corrosion cracking (SCC) which has its own dedicated standard ECSS-Q-ST-70-36. It covers typical spacecraft and launcher programmes on ground for a period of no more than 10 years. This standard may be tailored for the specific characteristic and constraints of a space project in conformance with ECSS-S-ST-00. SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 8 2 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 revision of any of these publications do not apply. However, parties to agreements based on this ECSS Standard are encouraged to investigate the possibility of applying the more 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 16602-70 ECSS-Q-ST-70 Space product assurance - Materials, mechanical parts and processes
ASTM D 5894-10 (2010) Standard Practice for Cyclic Salt Fog/UV Exposure of Painted Metal, (Alternating Exposures in a Fog/Dry Cabinet and a UV/Condensation Cabinet)
ISO 9227:2012 Corrosion tests in artificial atmospheres – Salt spray tests
ISO 9588:2007 Metallic and other inorganic coatings - Post-coating treatments of iron or steel to reduce the risk of hydrogen embrittlement
ISO 11130:2010 Corrosion of metals and alloys - Alternate immersion test in salt solution
MIL-STD-1501F (2011) Chromium Plating, Low Embrittlement, Electrodeposition SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 9 3 Terms, definitions and abbreviated terms 3.1 Terms from other standards a. For the purpose of this Standard, the terms and definitions from ECSS-S-ST-00-01 apply. b. For the purpose of this Standard, the terms and definitions from ECSS-Q-70-50 apply, in particular for the following terms: 1. representative sample 3.2 Terms specific to the present standard 3.2.1 corrosion gradual degradation of materials produced by chemical reaction with the environment or with fluids in contact with materials 3.2.2 corrosion resistant alloys alloys showing acceptable corrosion performance in most environments seen by space hardware NOTE
The use of corrosion resistant alloys does not mean that corrosion cannot occur in all environments. 3.2.3 corrosion-resistant aluminium alloys 1000, 3000, 5000, and 6000 series alloys and all clad alloys 3.2.4 corrosion-Resistant Steel (CRES) steel having 12 % in weight or more chromium content 3.2.5 exterior surfaces surface in contact with or exposed to direct action of the environment NOTE
All other surfaces are considered interior surfaces. 3.2.6 non-corrosion-resistant aluminium alloys all other aluminium alloys not considered to be corrosion-resistant alloys SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 10 3.2.7 non-corrosion-resistant steel steel having less than 12 % in weight chromium 3.3 Abbreviated terms For the purpose of this Standard, the abbreviated terms from ECSS-S-ST-00-01 and the following apply:
Abbreviation Meaning AD applicable document AMS aerospace material specification ASTM American Society for Testing and Materials CRES corrosion-resistant steel CVD chemical vapour deposition °C degree Celsius DML declared materials list DMPL declared mechanical parts list DPL declared process list DRD document requirements definition EN
European Norm H/W hardware ISO
International Standardisation Organisation MIL-STD military standard MPa Megapascal NSST Neutral Salt Spray Test PVD
physical vapour deposition RD reference document RH relative humidity SAE Society of Automotive Engineers SCC stress-corrosion cracking SST salt spray test UTS ultimate tensile strength UV ultraviolet
SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 11 3.4 Nomenclature The following nomenclature applies throughout this document: a. The word “shall” is used in this Standard to express requirements. All the requirements are expressed with the word “shall”. b. The word “should” is used in this Standard to express recommendations. All the recommendations are expressed with the word “should”. NOTE It is expected that, during tailoring, recommendations in this document are either converted into requirements or tailored out. c. The words “may” and “need not” are used in this Standard to express positive and negative permissions, respectively. All the positive permissions are expressed with the word “may”. All the negative permissions are expressed with the words “need not”. d. The word “can” is used in this Standard to express capabilities or possibilities, and therefore, if not accompanied by one of the previous words, it implies descriptive text. NOTE In ECSS “may” and “can” have completely different meanings: “may” is normative (permission), and “can” is descriptive. e. The present and past tenses are used in this Standard to express statements of fact, and therefore they imply descriptive text. SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 12 4 Principles 4.1 General Corrosion is the degradation of a material when exposed to an environment. Although corrosion usually refers to the degradation of metals and alloys. polymeric and ceramic materials can also degrade when exposed to an environment.
Clause 5.1.9 of ECSS-Q-ST-70 states that: a. “For all materials that come into contact with atmospheric gases, cleaning fluids or other chemicals, it shall be demonstrated that the degradation of properties during their anticipated service life does not prevent to meet the performance and integrity requirements”. b. “All mechanical parts, assemblies and equipment including spares, shall be finished to provide protection from corrosion. NOTE
This applies equally to fasteners and other fixing devices, such as insert systems.” 4.2 Eight forms of corrosion Corrosion is classified according to eight forms: 1) general, 2) galvanic, 3) pitting, 4) crevice, 5) erosion corrosion, 6) intergranular, 7) stress corrosion cracking, 8) dealloying or selective leaching.
A full explanation of eight forms of corrosion is given in Annex A. Although some corrosion processes can be considered benign or even advantageous, the by-products of such reactions should also be considered. For example, hydrogen is generated as a by-product of many corrosion reactions. SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 13 The original corrosion can be superficial but the hydrogen generated can result in delayed fracture in titanium, high strength steels and martensitic alloys. In the European Space Industry most corrosion problems experienced are associated with general corrosion, galvanic corrosion and pitting. Stress corrosion is covered by ECSS-Q-ST-70-36. 4.3 Corrosion protection It is possible to protect materials from corrosion. Corrosion protection systems compatible with the space environment are available and some examples are described in clauses 5.6, 5.7 and 5.8. NOTE
Selection of a corrosion protection system needs to ensure it complies with local environmental regulations. SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 14 5 Requirements 5.1 Classification of corrosive environments
The supplier shall identify, the applicable classes of environments from the list specified in the Table 5-1 to which space flight hardware materials are exposed during hardware life cycle on ground or during mission. NOTE
A non-exhaustive list of standards that can be agreed between customer and supplier is given in the bibliography of this standard.
The supplier shall select corrosion protection systems for each space flight hardware material.
The selection of the relevant class of corrosive environment shall be based on the worst-case hardware exposure. 1 The exterior surfaces are typically the worst-case exposure. However it is necessary to evaluate each hardware individually. 2 The manufacturer can decide to put (or not) surface protection on materials or parts inside a hermetically sealed enclosure, containing a non-corrosive atmosphere.
Degree of severity increases from Class 6 to Class 1, except for Class 4 that shall be considered apart from other classes. SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 15 Table 5-1: Definition of corrosive environment classes Class Definition
1 Exposure to seawater (immersion) 2 Exposure to marine (atmospheric) environments 3 Exposure to inland outdoor environments. (See note 1). 4 Exposure to potentially corrosive chemical systems or microbial induced corrosion.
5 Exposure to indoor and uncontrolled humidity environments. 6 Continuous and exclusive exposure to temperature and humidity controlled (non-condensing) environment, dry air, and nitrogen- purged environments (maximum 65 % RH). (See note 2). Note 1: The weather conditions and prevailing winds mean that most of Europe is considered a marine environment. Use of this class in Europe need dedicated justification showing a chloride deposition rate of less than 5 mg.m2/day (mean annual value). Note 2: Examples of temperature and humidity controlled environments are clean room, flight hardware controlled storage areas
5.2 Performance requirements
It shall be shown that all environmentally exposed surfaces are protected from corrosion or resistant to corrosion in accordance with the test methods specified in the Table 5-2.
All corrosion tests shall be conducted using alloys with the heat treatment specified in the design documentation of the hardware.
For alloys in the same family, the most corrosion-susceptible alloy may be agreed between a customer and supplier and tested in lieu of the testing of all alloys in that family. NOTE
Sometimes it is not possible to select a single alloy to represent a family.
The supplier shall perform corrosion tests for the most severe environmental conditions anticipated.
In case the tests specified in Table 5-2 cannot be performed or are not representative, alternative justified corrosion test regimes for specific applications shall be submitted for customer approval.
Test acceptance criteria shall be specified by the supplier and agreed with the customer. 1 A typical acceptance criteria can be “no visible signs of corrosion at 5X magnification and no material removed when tape tested in accordance with ISO 2409 standard without cuts”. 2 See Tape Test method in Annex B.
At the conclusion of testing, the test samples shall be evaluated in accordance with acceptance criteria specified in the requirement 5.2f. SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 16 5.3 Test samples definition
Test samples shall be representative of the material listed in DML and DMPL specified in DRDs Annex A and Annex B from ECSS-Q-ST-70.
Test samples specified in the requirement 5.3a shall be manufactured with the same materials as the flight hardware and representative of the material form, finish, thermal treatment and size. 1 Examples of material form are cast, forged or extruded. 2 A typical sample has a minimum area of 1 dm2. In the case of small flight hardware, a smaller sample size can be acceptable.
A minimum number of test samples shall be subject to the customer approval. 5.4 Test methods
Overview The following clauses provide additional information on test methods versus environmental classes listed in Table 5-2.
SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 17 Table 5-2– Matrix of test methods versus environments Test Method Applicable Test Standard Environment Class
1 2 3 4 5 6 Seawater Immersion Seacoast, Outdoor Inland, Outdoor Chemical or Microbial Indoor uncontrolled Indoor controlled Neutral Salt Spray Test (NSST) ISO 9227
500 h alternating with UV test
168 h
Chemical Resistance See Note 1
Specific test in accordance with corrosive agents
Damp Heat Test Damp Heat Test (see Annex C) (93 % RH 40 °C)
240 h UV ASTM D5894
7 days alternating with NSST
Alternate immersion ISO 11130 2x maximum allowed exposure 30 days
Note 1 Because for the environment class 4 there are no applicable test standards, the specific test in accordance with corrosive agents is performed.
SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 18
Class 1: Seawater Immersion
In Class 1 environments, the protective finish shall withstand two times the maximum defined duration of immersion in seawater, when tested in accordance with ISO 11130.
Class 2: Seacoast, Outdoor
In Class 2 environments, the protective finish shall withstand 30 days when tested in accordance with ISO 11130.
Class 3: Inland, Outdoor
In Class 3 environments, the protective finish shall be tested by a combination of UV and NSST.
In Class 3 environments, the protective finish shall be tested alternating NSST and UV test, starting with UV testing.
In Class 3 environments, the total duration of test specified in the requirement 5.4.4b shall be seven days for UV and 500 h for NSST.
Class 4: Chemical or Microbial-Induced Corrosion
In Class 4 environments, specific tests shall be performed to confirm that the hardware is protected against corrosion during the anticipated chemical exposure or during exposure to microorganisms that induce corrosion.
Class 5: Indoor, Uncontrolled
In Class 5 environments, the hardware or representative samples shall be tested for 168 h in accordance with Neutral Salt Spray Test from ISO 9227.
Class 6: Indoor, Controlled
In Class 6 environments, all exposed surfaces shall be maintained in a continuous exposure to temperature- and humidity-controlled non-condensing environments. NOTE
Examples of non-condensing environments include clean room, flight hardware controlled storage areas.
In Class 6 environments, the corrosion resistance shall be tested for 240 h in accordance with Damp Heat Test at (93 ±3)% RH and (40 ±3)°C. NOTE
The Damp Heat Test method is described in Annex C. SIST EN 16602-70-14:2019



EN 16602-70-14:2018 (E) 19 5.5 Corrosion protection
Process verification
For processes used for corrosion protection the supplier shall implement a verification programme.
The verification program shall be defined in accordance with the test methods specified in 5.4.
The process verification shall indicate the test methods used for process verification and the requirements to be met. NOTE
Depending on process and application additional testing can be performed. For example dry film thickness, coating adhesion, flexibility, abrasion resistance, and impact resistance testing can be performed if appropriate.
Process maturity and sensitivity studies shall be performed to establish processing parameters for protective finishes being qualified.
The process parameters specified in the requirement 5.5.1d shall be defined in the process specification.
Cleaning and surface preparation
Cleaning and surface preparation requirements shall be included in the surface treatment technical specification.
At the time of application of any finish, all surfaces shall be clean and free from dirt, grease, oil, or any contamination that can interfere with the performance of the finish of the part.
Cleaning methods or solutions used shall not affect the functioning of the part or application of the finish.
Steel and aluminium wools shall not be used.
The use of wire brushes shall be restricted to the same alloy type.
NOTE
Carbon steel brushes on carbon or low-alloy steel structures are examples of wire brushes.
Austenitic stainless steel brushes may be used on other alloy classes provided that: 1. use of the brush is restricted to a single alloy, or 2. the brush is cleaned, rinsed, and dried before use on a different alloy.
All cleaning fluids and other chemicals used during manufacturing and processing of h
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