Additive manufacturing - Process characteristics and performance - Practice for metal powder bed fusion process to meet critical applications (ISO/ASTM 52904:2019)

1.1 This practice describes the operation and production control of metal powder bed fusion (PBF) machines and processes to meet critical applications such as commercial aerospace components and medical implants. The requirements contained herein are applicable for production components and mechanical test specimens using powder bed fusion (PBF) with both laser and electron beams.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.
1.3 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for the Development of International Standards, Guides and Recom-mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

Additive Fertigung - Prozessanforderungen und Qualifizierung - Verwendung des pulverbettbasierten Schmelzens von Metallen bei kritischen Anwendungen (ISO/ASTM 52904:2019)

1.1 Diese Praxis beschreibt den Betrieb und die Produktionskontrolle von PBF Maschinen und  Prozessen (pulverbettbasiertes Schmelzen, en: powder bed fusion), um kritische Anwendungsanforderungen für beispielsweise kommerzielle Bauelemente für die Luft  und Raumfahrt und medizinische Implantate zu erfüllen. Die in diesem Dokument enthaltenen Anforderungen gelten für Fertigungskomponenten und mechanische Probekörper unter Verwendung des pulverbettbasierten Schmelzens (PBF) mit Laser  und Elektronenstrahlen.
1.2 Diese Norm gibt nicht vor, alle unter Umständen mit der Anwendung des Verfahrens verbundenen Sicherheitsaspekte zu behandeln. Es liegt in der Verantwortung des Anwenders dieses Dokuments, geeignete Vorkehrungen für den Arbeits , Gesundheits  und Umweltschutz zu treffen und vor der Anwendung festzulegen, welche einschränkenden Vorschriften gelten.
1.3 Diese internationale Norm wurde in Übereinstimmung mit den interational anerkannten Grundsätzen der Normung entwickelt, die in der Entscheidung über die Grundsätze für die Entwicklung internationaler Normen, Leitfäden und Empfehlungen des Ausschusses für technische Handelshemmnisse (TBT) der Welthandelsorganisation festgelegt sind.

Fabrication additive - Caractéristiques et performances du procédé - Pratique du procédé de fusion sur lit de poudre métallique en vue de répondre aux applications critiques (ISO/ASTM 52904:2019)

1.1    La présente pratique décrit le fonctionnement et le contrôle de production des machines et des procédés de fusion sur lit de poudre métallique (PBF) pour répondre à des applications critiques, telles que les composants aérospatiaux commerciaux et les implants médicaux. Les exigences contenues ci-après sont applicables aux composants de production et aux éprouvettes d'essai mécaniques utilisant la fusion sur lit de poudre (PBF) avec des faisceaux laser et électroniques.
1.2    La présente norme ne prétend pas traiter de tous les problèmes de sécurité, s'ils existent, associés à son utilisation. Il est de la responsabilité de l'utilisateur de la présente norme d'établir des pratiques de sécurité, d'hygiène et d'environnement appropriées, et de déterminer l'applicabilité des restrictions réglementaires avant utilisation.
1.3    La présente Norme internationale a été élaborée conformément aux principes internationalement reconnus de normalisation établis dans la Décision sur les principes pour l'élaboration de normes internationales, guides et recommandations publiée par le Comité des obstacles techniques au commerce (OTC) de l'Organisation mondiale du commerce.

Aditivna proizvodnja - Značilnosti in tehnične lastnosti procesa - Ravnanje pri procesu fuzije plasti kovinskih prašnih delcev za doseganje kritičnih aplikacij (ISO/ASTM 52904:2019)

General Information

Status
Published
Public Enquiry End Date
31-Mar-2020
Publication Date
21-Jun-2020
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
18-Jun-2020
Due Date
23-Aug-2020
Completion Date
22-Jun-2020

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO/ASTM 52904:2020
01-september-2020
Aditivna proizvodnja - Značilnosti in tehnične lastnosti procesa - Ravnanje pri
procesu fuzije plasti kovinskih prašnih delcev za doseganje kritičnih aplikacij
(ISO/ASTM 52904:2019)
Additive manufacturing - Process characteristics and performance - Practice for metal
powder bed fusion process to meet critical applications (ISO/ASTM 52904:2019)
Additive Fertigung - Prozessanforderungen und Qualifizierung - Verwendung des
pulverbettbasierten Schmelzens von Metallen bei kritischen Anwendungen (ISO/ASTM
52904:2019)
Fabrication additive - Caractéristiques et performances du procédé - Pratique du
procédé de fusion sur lit de poudre métallique en vue de répondre aux applications
critiques (ISO/ASTM 52904:2019)
Ta slovenski standard je istoveten z: EN ISO/ASTM 52904:2020
ICS:
25.030 3D-tiskanje Additive manufacturing
SIST EN ISO/ASTM 52904:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO/ASTM 52904:2020

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SIST EN ISO/ASTM 52904:2020


EN ISO/ASTM 52904
EUROPEAN STANDARD

NORME EUROPÉENNE

June 2020
EUROPÄISCHE NORM
ICS 25.030
English Version

Additive manufacturing - Process characteristics and
performance - Practice for metal powder bed fusion
process to meet critical applications (ISO/ASTM
52904:2019)
Fabrication additive - Caractéristiques et performances Additive Fertigung - Prozessanforderungen und
du procédé - Pratique du procédé de fusion sur lit de Qualifizierung - Verwendung des pulverbettbasierten
poudre métallique en vue de répondre aux applications Schmelzens von Metallen bei kritischen Anwendungen
critiques (ISO/ASTM 52904:2019) (ISO/ASTM 52904:2019)
This European Standard was approved by CEN on 10 May 2020.

CEN 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
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 member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO/ASTM 52904:2020 E
worldwide for CEN national Members.

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SIST EN ISO/ASTM 52904:2020
EN ISO/ASTM 52904:2020 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO/ASTM 52904:2020
EN ISO/ASTM 52904:2020 (E)
European foreword
The text of ISO/ASTM 52904:2019 has been prepared by Technical Committee ISO/TC 261 "Additive
manufacturing” of the International Organization for Standardization (ISO) and has been taken over as
EN ISO/ASTM 52904:2020 by Technical Committee CEN/TC 438 “Additive Manufacturing” the
secretariat of which is held by AFNOR.
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 December 2020, and conflicting national standards
shall be withdrawn at the latest by December 2020.
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.
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, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO/ASTM 52904:2019 has been approved by CEN as EN ISO/ASTM 52904:2020 without
any modification.

3

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SIST EN ISO/ASTM 52904:2020

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SIST EN ISO/ASTM 52904:2020
INTERNATIONAL ISO/ASTM
STANDARD 52904
First edition
2019-08
Additive manufacturing — Process
characteristics and performance —
Practice for metal powder bed fusion
process to meet critical applications
Fabrication additive — Caractéristiques et performances du
procédé — Pratique du procédé de fusion sur lit de poudre métallique
en vue de répondre aux applications critiques
Reference number
ISO/ASTM 52904:2019(E)
©
ISO/ASTM International 2019

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SIST EN ISO/ASTM 52904:2020
ISO/ASTM 52904:2019(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO/ASTM International 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be
reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester. In the United States, such requests should be sent to ASTM International.
ISO copyright office ASTM International
CP 401 • Ch. de Blandonnet 8 100 Barr Harbor Drive, PO Box C700
CH-1214 Vernier, Geneva West Conshohocken, PA 19428-2959, USA
Phone: +41 22 749 01 11 Phone: +610 832 9634
Fax: +41 22 749 09 47 Fax: +610 832 9635
Email: copyright@iso.org Email: khooper@astm.org
Website: www.iso.org Website: www.astm.org
Published in Switzerland
ii © ISO/ASTM International 2019 – All rights reserved

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SIST EN ISO/ASTM 52904:2020
ISO/ASTM 52904:2019(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national
standards bodies (ISO member bodies). The work of preparing International Standards is normally
carried out through ISO technical committees. Each member body interested in a subject for which a
technical committee has been established has the right to be represented on that committee.
International organizations, governmental and non‐governmental, in liaison with ISO, also take part
in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all
matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for
the different types of ISO documents should be noted (see www.iso.org/directives).
ASTM International is one of the world’s largest voluntary standards development organizations
with global participation from affected stakeholders. ASTM technical committees follow rigorous
due process balloting procedures.
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and ASTM International shall not be held responsible for identifying any or all
such patent rights. Details of any patent rights identified during the development of the document
will be in the Introduction and/or on the ISO list of patent declarations received
(see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does
not constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT),
see www.iso.org/iso/foreword.html.
This document was prepared by ASTM Committee F42, Additive Manufacturing Technologies (as
ASTM F3303‐2018), and drafted in accordance with its editorial rules. It was assigned to Technical
Committee ISO/TC 261, Additive manufacturing, and adopted under the “fast‐track procedure”.
Any feedback or questions on this document should be directed to the user’s national standards
body. A complete listing of these bodies can be found at www.iso.org/members.html.
© ISO/ASTM International 2019 – All rights reserved

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SIST EN ISO/ASTM 52904:2020

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SIST EN ISO/ASTM 52904:2020
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
ISO/ASTM 52904:2019(E)
Designation: F3303 − 2018
Standard for
Additive Manufacturing – Process Characteristics and
Performance: Practice for Metal Powder Bed Fusion
1
Process to Meet Critical Applications
This standard is issued under the fixed designation F3303; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E2910 Guide for Preferred Methods for Acceptance of
Product
1.1 This practice describes the operation and production
F2924 Specification for Additive Manufacturing Titanium-6
control of metal powder bed fusion (PBF) machines and
Aluminum-4 Vanadium with Powder Bed Fusion
processes to meet critical applications such as commercial
F2971 Practice for Reporting Data for Test Specimens Pre-
aerospacecomponentsandmedicalimplants.Therequirements
pared by Additive Manufacturing
contained herein are applicable for production components and
F3049 Guide for Characterizing Properties of Metal Pow-
mechanicaltestspecimensusingpowderbedfusion(PBF)with
ders Used for Additive Manufacturing Processes
both laser and electron beams.
F3122 Guide for Evaluating Mechanical Properties of Metal
1.2 This standard does not purport to address all of the
Materials Made via Additive Manufacturing Processes
safety concerns, if any, associated with its use. It is the
2
2.3 ISO/ASTM Standards:
responsibility of the user of this standard to establish appro-
52900 Standard Terminology for Additive Manufacturing –
priate safety, health, and environmental practices and deter-
General Principles – Terminology
mine the applicability of regulatory limitations prior to use.
52921 Terminology for Additive Manufacturing – Coordi-
1.3 This international standard was developed in accor-
nate Systems and Test Methodologies
dance with internationally recognized principles on standard-
3
ization established in the Decision on Principles for the
2.4 ISO Standards:
Development of International Standards, Guides and Recom- 4497 Metallic powders – Determination of particle size by
mendations issued by the World Trade Organization Technical
dry sieving
Barriers to Trade (TBT) Committee. D6892–1 Metallic materials – Tensile testing at ambient
temperature
2. Normative References
D6892–2 Metallic materials – Tensile testing – Part 2:
2.1 The following documents are referred to in the text in
Method of test at elevated temperature
such a way that some or all of their content constitutes 8573-1 Compressed air – Part 1: Contaminants and purity
requirements of this document. For dated references, only the
classes
edition cited applies. For undated references, the latest edition 9001 Quality management systems – Requirements
of the referenced document (including any amendments) ap-
9044 Industrial Woven Wire Cloth – Technical Require-
plies. ments and Testing
2
13320 Particle size analysis – Laser diffraction methods
2.2 ASTM Standards:
13485 Medical devices – Quality management systems –
E8/E8M Test Methods for Tension Testing of Metallic Ma-
Requirements for regulatory purposes
terials
E11 Specification for Woven Wire Test Sieve Cloth and Test
2.5 Other Standards:
Sieves ANSI/ASQC C1-1996 Specification of General Require-
4
ments for a Quality Program
AS9100 Quality Management Systems - Requirements for
1
This practice is under the jurisdiction of ASTM Committee F42 on Additive
Manufacturing Technologies and is the direct responsibility of Subcommittee
F42.05onMaterialsandProcesses,andisalsounderthejurisdictionofISO/TC261.
Current edition approved Feb. 1, 2018. Published June 2018. DOI: 10.1520/
3
F3303-18. Available from International Organization for Standardization (ISO), ISO
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier,
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Geneva, Switzerland, http://www.iso.org.
4
Standards volume information, refer to the standard’s Document Summary page on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
© ISO/ASTM International 2019 – All rights reserved
1

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SIST EN ISO/ASTM 52904:2020
ISO/ASTM 52904:2019(E)
F3303 − 2018
5
Aviation, Space, and Defense Organizations 5.3 Metal powder shall be purchased from an approved
material supplier on the QMS (Quality Management Systems
3. Terms and Definitions (see 6.3)), an ASL (Approved Supplier List), or a customer-
directed material supplier. Powder shall be verified for confor-
3.1 For the purposes of this document, the terms and
mance to the material specification. Third-party certification of
definitions given in Specification F2924, ISO/ASTM 52900,
powder may be used. Guide F3049, ISO 4497, and ISO 13320
ISO/ASTM 52921, Guide E2910, and the following apply.
provide guidance on the measurement of particle size distribu-
3.2 ISO and IEC maintain terminological databases for use
tion.
in standardization at the following addresses:
5.4 The component manufacturer shall have a feedstock
– IEC Electropedia available at http://
material specification against which feedstock can be ordered
www.electropedia.org/
and tested. Feedstock used for qualification purposes may
– ISO Online browsing platform available at https://
require a limited reused powder such that the powder utilized
www.iso.org/obp
for one qualification build to another remains as consistent as
3.3 Definitions:
practical(forexample,byusingvirginfeedstockasthepurpose
3.3.1 build programmer—person responsible for program-
of the qualification is to check the consistency of machine
ming a build including part orientation, part(s) nesting, and the
operation over time).
application of critical build parameters.
5.4.1 A feedstock material specification shall include, but
3.3.2 machine operator—person responsible for initiating not be limited to, chemical composition, particle size
builds and turning over machines, which includes, but is not
distribution, and manufacturing methodology.
limited to, loading feedstock powder, loading build platforms,
5.5 Powder shall be stored in environmental containment to
removing completed builds and routine machine cleaning and
prevent contamination and moisture absorption.
filter changes.
5.6 Used powder is allowed (see 7.1.1.4.1 for requirement
3.3.3 recoater blade—portion of the machine that comes in
on used powder that is processed with ceramic recoater
contact with and spreads feedstock across the build area.
blade).The proportion of virgin to used powder shall be
3.3.3.1 Discussion—Therecoaterblademayalsobecalleda
recorded and reported for each production run on the manu-
rake, recoater, roller, or brush.
facturing plan (Section 10). Automated powder feed systems
may not allow the proportion of virgin to used powder to be
4. PBF Material Identification
accurately measured and recorded on the manufacturing plan.
4.1 Material covered by this document (that is, powder and
Insuchsystemsthefeedstockshallbeconsideredusedpowder.
consolidated part/PBF machine input and output), shall be
The maximum number of times that used powder can be
identifiedbyspecificationcalloutsincluding,butnotlimitedto,
consumed as well as the number of times any portion of a
the following:
powder lot can be processed in the build chamber shall be
4.1.1 Alloy designation according to requirements; where
validated in accordance with 7.3. After a build cycle, any
no alloy designation exists, the chemical composition shall be
remaining used powder may be blended with virgin powder to
listed.
maintain a powder quantity large enough for the next build
4.1.2 Powder type—Virgin, used, blend or mix.
cycle.Thecriticalpowderattributesimpactingqualificationsin
4.1.3 Surface finish—As built, media blasted, supports re-
accordance with 7.3 shall be analyzed regularly. All used
moved by machining or manual deburring, in accordance with
powder shall be sieved with a sieve having a mesh size
specification callouts, or any combination of the latter finish
appropriate for removing any agglomerations. All powder
types.
sieves used to manufacture parts shall have a certificate of
4.1.4 Dimensional tolerances—In accordance with specifi-
conformance that they were manufactured to ISO 9044 or
cation callouts or PBF machine output capability.
Specification E11.
NOTE 1—4.1.3 and 4.1.4 apply to consolidated parts only.
6. Personnel Requirements
6.1 Personnel competency requirements in ISO 13485 shall
5. Feedstock and Powder Batches
apply, including appropriate education, training, skills, and
5.1 The material supplier shall package the powder in
experience.
containers capable of preventing moisture from penetrating the
containers. No other materials including desiccant bags, labels, 6.2 Manufacturing manager, machine operator, or build
programmer (as defined in Section 3) shall be trained by the
or tags shall be placed inside the containers in contact with the
powder. machine manufacturer or qualified agency for PBF machine
hardware and software, where appropriate.
5.2 All feedstock shall have a certificate of conformance
from the material supplier indicating that the feedstock meets 6.3 On machines that are qualified in accordance with 7.3,
the machine manufacturer shall provide for continuing educa-
the purchase specification requirements.
tion as new hardware and software releases are purchased and
implemented. Records of such training shall be maintained in
5
employee training folders in accordance with a local Quality
Available from SAE International (SAE), 400 Commonwealth Dr.,Warrendale,
PA 15096, http://www.sae.org. Management System (for example, ISO 9001, ISO 13485,
© ISO/ASTM International 2019 – All rights reserved
2

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SIST EN ISO/ASTM 52904:2020
ISO/ASTM 52904:2019(E)
F3303 − 2018
Designation: F3303 − 2018
ASQC C1, AS 9100) for reference with customers or outside 7.1.1.8 External gas—Gas type and flow shall meet the
regulatory agencies, or both. machine manufacturer’s recommendation for the feedstock.
7.1.1.9 Feedstock and baseline machine and process
6.4 Only persons trained in accordance with 6.1 and 6.2
parameters—Ensure that feedstock and parameters (for
shall be considered qualified personnel.
example, beam offset, beam parameters, input energy) are
correct for build.
7. Qualification
7.1.1.10 Beam power verification—The instructions for
7.1 Pre-Build Checks
checking the laser or electron beam power shall be determined
7.1.1 This section describes pre-build checks applied to all
by the component manufacturer and recorded in a QMS
builds independently of their purpose (for example, periodic
document. Laser or electron beam power shall be measured
preventive maintenance, machine/process qualification,
and documented in the manufacturing plan immediately prior
scaling/calibration builds, etc.). The pre-build checks shall
to build initiation and following the completion of all builds.
include, but not be limited to:
7.1.1.11 Part files, orientation and location—All part files
7.1.1.1 Maintenance record—Checkthemaintenancerecord
related to the digital geometry (for example, STL, AMF) shall
(see 7.2.2) and qualification status of machine (see 7.3).
match the intended revision, the part orientation and location
7.1.1.2 Required feedstock quantity—Verify that required
on the build platform, as stated in the manufacturing plan.
quantity for build is available.
7.1.1.12 Machining stock—Ensure that machining stock is
7.1.1.3 Build platform (also known as build plate or start
added to part(s) in accordance with manufacturing plan.
plate)—Ensure that the build platform serial number matches
7.1.1.13 Parts nesting—The build platform part nesting, as
the one specified in the manufacturing plan (Section 10). The
displayed by the PBF build processor software, shall be
build platform shall be free from any surface contamination
recorded (for example with a screen shot).
(including dirt, oil, or grease), and any form of defects
7.2 Periodic Preventive Maintenance (Third Party Accredi-
resulting in an inconsistent powder bed. Build platforms shall
tation)
be visually inspected and rejected for any obvious damage or
7.2.1 PBF machines shall undergo preventive maintenance
non-conformity. Platform shall be installed in PBF machine
(PM) by trained technicians in accordance with the machine
using the proper QMS instructions.
manufacturer’s recommended frequency (for example, mini-
7.1.1.4 Recoater blade—Ensure material compatibility with
mum of every six months or after a given number of build
feedstock and consolidated material, cleanliness, absence of
hours). PBF machines where preventive maintenance has
any form of defects resulting in an inconsistent powder bed,
lapsed shall not be used to meet the requirements herein. The
and consistent recoater clearance to the build platform at all
maintenance procedure shall confirm the effective function and
locations in conjunction with 10.1.2.2.
operations of each major machine and machine component that
7.1.1.4.1 Before initiating a PBF machine build, the recoater
affects product quality. This shall include, but not be limited to:
blade shall be inspected. The machine operator shall visually
7.2.1.1 Laser or electron beam power—Ensure that beam
inspectandverifythattherecoaterbladeisfreefromanychips,
characteristics are within the machine manufacturer’s recom-
scratches, debris or deformities and installed in accordance
mended tolerance. Test that the laser or electron beam output
with the machine manufacturer’s recommendations. Only
matches software set point in accordance with the machine
qualified materials shall be used on a PBF machine in
manufacturer’s recommendation or specification requirements,
accordance with 7.3.The chemical composition of the recoater
whichever is more demanding. Users of power meters should
blade shall be recorded on the manufacturing plan. PBF
consider the detector calibration uncertainty when measuring
machines with polymer recoater blade shall be validated to
and monitoring laser power. More comprehensive beam quality
show the polymer does not contaminate the feedstock by
measurements may be imposed on the machine vendor for
analyzing and pairing the chemical composition of powder
machine acceptance, for example, switch on/off speed, power
feedstock and that of consolidated part.When inspection is not
fluctuations after hours of operation, and beam profile devia-
possible due to installation location, polymer recoater blades
tions across the build platform. It is beyond the scope of this
should be replaced with a new one after the completion of each
standard to specify machine acceptance criteria.
build. Used feedstock processed with a ceramic recoater blade
7.2.1.2 Beam power at build platform—When possible,
shall not be further processed. This section does not apply to
measure laser or electron beam power at left, right, front and
PBF machines that only use rollers to spread the powder.
back of build platform (that is, build platform extremities), but
7.1.1.5 Auxiliary systems (for example, shield gas, filters)—
at a minimum in the center of the build platform at 100% laser
Ensure correct type, proper function, and cleanliness of auxil-
power or as required for electron beam. Laser or electron beam
iary systems (grade 4.8 minimum for shielding gas).
power for each energy source shall be within the machine
7.1.1.6 Chiller temperature and flow of heat transfer fluid—
manufacturer’s recommendation or specification requirements,
Check chillier temperature and flow of heat transfer fluid (if
whichever is more demanding at all measurement locations.
applicable, in accordance with the machine manufacturer’s
recommendation). Record chiller temperature on the manufac-
NOTE 2—Beam quality and power measurements specified in 7.2.1.1
and 7.2.1.2 are for in-process control to prevent unintended changes in
turing plan prior to every build cycle.
energy density.
7.1.1.7 Build chamber environment—For machines that
have protective gas filters there shall be no flow restriction 7.2.1.3 Beam positioning verification—Ensure that
during machine operation. software-indicated beam location and actual beam position are
© ISO/ASTM International 2019 – All rights reserved
3

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SIST EN ISO/ASTM 52904:2020
ISO/ASTM 52904:2019(E)
F3303 − 2018
within tolerances recommended by the machine manufacturer mechanical properties as specified by an appropriate standard
or within tolerances specified by the component manufacturer. or as agreed upon by the component manufacturer and cus-
tomer. Chemical composition of the test specimens shall be
7.2.1.4 Z-axis movement—Ensure that software-controlled
and actual layer movements are within the machine manufac- verified against chemical composition requirements as indi-
cated by the consolidated material specification. The compo-
turer’s recommendation or specification requirements, which-
ever is more demanding. nentmanufacturershallfabricateASTME8,E8M,orISO6892
tension test blanks and additional test specimens placed, at a
7.2.1.5 Recoater arm and motor—Recoater blade alignment
minimum, in five locations on the build platform as shown in
shall be within the machine manufacturer’s recommended
Fig.1.Additionaltensiontestspecimensbuiltinthe Zdirection
tolerance.
are encouraged, but not required. Guide F3122 provides
7.2.1.6 Compressed air—Compressed air required for the
guidance on evaluating mechanical properties of metal mate-
PBF machine shall be checked at each PM for any contami-
rials made using PBF. The customer may require other quali-
nation in accordance with ISO 8573-1. Adjust to proper
ficationtests.Testresultsshallbesubmittedtothecustomerfor
pressure and check all fittings and connections.
approval in a format conforming to Practice F2971. Once
7.2.1.7 Oxygen and vacuum—Oxygen sensors shall be re-
approved, all the machine parameters used to make the test
placed in accordance with the machine manufacturer’s recom-
specimens shall be fixed to establish machine baseline param-
mended schedule and calibrated at a minimum of two oxygen
eters.Acertificate indicating the machine conforms to baseline
concentration points. Vacuum shall meet the machine manu-
parameters shall be posted in clear view of the machine
facturer’s recommendation and shall have a method for cali-
operators, and shall remain effective on all subsequent build
bration.
cycles until the PBF machine requires a new qualification.
7.2.1.8 Laser field alignment (LFA)—The LFA on multiple-
7.3.3.1 If required by the customer specification, the gage
laser systems shall be calibrated according to the machine
section of the tension test specimen may be left in the as built
manufacturer’srecommendations.Qualifiedmachinemanufac-
condition,providedtherearenosupportstructuresaddedtothe
turer shall provide tolerance requirements for laser field
gage section during the PBF process.
alignment.
7.3.3.2 The component manufacturer and customer shall
7.2.1.9 Other recommended preventive maintenance—
agree to the method for demonstrating consistency across the
Ensure that all other recommended preventive maintenance, as
build platform for systems with multiple energy sources.
listed in the machine operation or service manual, is per-
formed.
NOTE 3—Methods that tested five specimens from each build area
7.2.2 Record of maintenance activity shall b
...

SLOVENSKI STANDARD
oSIST prEN ISO/ASTM 52904:2020
01-marec-2020
Aditivna proizvodnja - Značilnosti in tehnične lastnosti procesa - Ravnanje pri
procesu fuzije plasti kovinskih prašnih delcev za doseganje kritičnih aplikacij
(ISO/ASTM 52904:2019)
Additive manufacturing - Process characteristics and performance - Practice for metal
powder bed fusion process to meet critical applications (ISO/ASTM 52904:2019)
Additive Fertigung - Prozessanforderungen und Qualifizierung - Verwendung des
pulverbettbasierten Schmelzens von Metallen bei kritischen Anwendungen (ISO/ASTM
52904:2019)
Fabrication additive - Caractéristiques et performances du procédé - Pratique du
procédé de fusion sur lit de poudre métallique en vue de répondre aux applications
critiques (ISO/ASTM 52904:2019)
Ta slovenski standard je istoveten z: prEN ISO/ASTM 52904
ICS:
25.030 3D-tiskanje Additive manufacturing
oSIST prEN ISO/ASTM 52904:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO/ASTM 52904:2020

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oSIST prEN ISO/ASTM 52904:2020
INTERNATIONAL ISO/ASTM
STANDARD 52904
First edition
2019-08
Additive manufacturing — Process
characteristics and performance —
Practice for metal powder bed fusion
process to meet critical applications
Fabrication additive — Caractéristiques et performances du
procédé — Pratique du procédé de fusion sur lit de poudre métallique
en vue de répondre aux applications critiques
Reference number
ISO/ASTM 52904:2019(E)
©
ISO/ASTM International 2019

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oSIST prEN ISO/ASTM 52904:2020
ISO/ASTM 52904:2019(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO/ASTM International 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be
reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester. In the United States, such requests should be sent to ASTM International.
ISO copyright office ASTM International
CP 401 • Ch. de Blandonnet 8 100 Barr Harbor Drive, PO Box C700
CH-1214 Vernier, Geneva West Conshohocken, PA 19428-2959, USA
Phone: +41 22 749 01 11 Phone: +610 832 9634
Fax: +41 22 749 09 47 Fax: +610 832 9635
Email: copyright@iso.org Email: khooper@astm.org
Website: www.iso.org Website: www.astm.org
Published in Switzerland
ii © ISO/ASTM International 2019 – All rights reserved

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oSIST prEN ISO/ASTM 52904:2020
ISO/ASTM 52904:2019(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national
standards bodies (ISO member bodies). The work of preparing International Standards is normally
carried out through ISO technical committees. Each member body interested in a subject for which a
technical committee has been established has the right to be represented on that committee.
International organizations, governmental and non‐governmental, in liaison with ISO, also take part
in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all
matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for
the different types of ISO documents should be noted (see www.iso.org/directives).
ASTM International is one of the world’s largest voluntary standards development organizations
with global participation from affected stakeholders. ASTM technical committees follow rigorous
due process balloting procedures.
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and ASTM International shall not be held responsible for identifying any or all
such patent rights. Details of any patent rights identified during the development of the document
will be in the Introduction and/or on the ISO list of patent declarations received
(see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does
not constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT),
see www.iso.org/iso/foreword.html.
This document was prepared by ASTM Committee F42, Additive Manufacturing Technologies (as
ASTM F3303‐2018), and drafted in accordance with its editorial rules. It was assigned to Technical
Committee ISO/TC 261, Additive manufacturing, and adopted under the “fast‐track procedure”.
Any feedback or questions on this document should be directed to the user’s national standards
body. A complete listing of these bodies can be found at www.iso.org/members.html.
© ISO/ASTM International 2019 – All rights reserved

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oSIST prEN ISO/ASTM 52904:2020

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oSIST prEN ISO/ASTM 52904:2020
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
ISO/ASTM 52904:2019(E)
Designation: F3303 − 2018
Standard for
Additive Manufacturing – Process Characteristics and
Performance: Practice for Metal Powder Bed Fusion
1
Process to Meet Critical Applications
This standard is issued under the fixed designation F3303; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E2910 Guide for Preferred Methods for Acceptance of
Product
1.1 This practice describes the operation and production
F2924 Specification for Additive Manufacturing Titanium-6
control of metal powder bed fusion (PBF) machines and
Aluminum-4 Vanadium with Powder Bed Fusion
processes to meet critical applications such as commercial
F2971 Practice for Reporting Data for Test Specimens Pre-
aerospacecomponentsandmedicalimplants.Therequirements
pared by Additive Manufacturing
contained herein are applicable for production components and
F3049 Guide for Characterizing Properties of Metal Pow-
mechanicaltestspecimensusingpowderbedfusion(PBF)with
ders Used for Additive Manufacturing Processes
both laser and electron beams.
F3122 Guide for Evaluating Mechanical Properties of Metal
1.2 This standard does not purport to address all of the
Materials Made via Additive Manufacturing Processes
safety concerns, if any, associated with its use. It is the
2
2.3 ISO/ASTM Standards:
responsibility of the user of this standard to establish appro-
52900 Standard Terminology for Additive Manufacturing –
priate safety, health, and environmental practices and deter-
General Principles – Terminology
mine the applicability of regulatory limitations prior to use.
52921 Terminology for Additive Manufacturing – Coordi-
1.3 This international standard was developed in accor-
nate Systems and Test Methodologies
dance with internationally recognized principles on standard-
3
ization established in the Decision on Principles for the
2.4 ISO Standards:
Development of International Standards, Guides and Recom- 4497 Metallic powders – Determination of particle size by
mendations issued by the World Trade Organization Technical
dry sieving
Barriers to Trade (TBT) Committee. D6892–1 Metallic materials – Tensile testing at ambient
temperature
2. Normative References
D6892–2 Metallic materials – Tensile testing – Part 2:
2.1 The following documents are referred to in the text in
Method of test at elevated temperature
such a way that some or all of their content constitutes 8573-1 Compressed air – Part 1: Contaminants and purity
requirements of this document. For dated references, only the
classes
edition cited applies. For undated references, the latest edition 9001 Quality management systems – Requirements
of the referenced document (including any amendments) ap-
9044 Industrial Woven Wire Cloth – Technical Require-
plies. ments and Testing
2
13320 Particle size analysis – Laser diffraction methods
2.2 ASTM Standards:
13485 Medical devices – Quality management systems –
E8/E8M Test Methods for Tension Testing of Metallic Ma-
Requirements for regulatory purposes
terials
E11 Specification for Woven Wire Test Sieve Cloth and Test
2.5 Other Standards:
Sieves ANSI/ASQC C1-1996 Specification of General Require-
4
ments for a Quality Program
AS9100 Quality Management Systems - Requirements for
1
This practice is under the jurisdiction of ASTM Committee F42 on Additive
Manufacturing Technologies and is the direct responsibility of Subcommittee
F42.05onMaterialsandProcesses,andisalsounderthejurisdictionofISO/TC261.
Current edition approved Feb. 1, 2018. Published June 2018. DOI: 10.1520/
3
F3303-18. Available from International Organization for Standardization (ISO), ISO
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier,
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Geneva, Switzerland, http://www.iso.org.
4
Standards volume information, refer to the standard’s Document Summary page on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
the ASTM website. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
© ISO/ASTM International 2019 – All rights reserved
1

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oSIST prEN ISO/ASTM 52904:2020
ISO/ASTM 52904:2019(E)
F3303 − 2018
5
Aviation, Space, and Defense Organizations 5.3 Metal powder shall be purchased from an approved
material supplier on the QMS (Quality Management Systems
3. Terms and Definitions (see 6.3)), an ASL (Approved Supplier List), or a customer-
directed material supplier. Powder shall be verified for confor-
3.1 For the purposes of this document, the terms and
mance to the material specification. Third-party certification of
definitions given in Specification F2924, ISO/ASTM 52900,
powder may be used. Guide F3049, ISO 4497, and ISO 13320
ISO/ASTM 52921, Guide E2910, and the following apply.
provide guidance on the measurement of particle size distribu-
3.2 ISO and IEC maintain terminological databases for use
tion.
in standardization at the following addresses:
5.4 The component manufacturer shall have a feedstock
– IEC Electropedia available at http://
material specification against which feedstock can be ordered
www.electropedia.org/
and tested. Feedstock used for qualification purposes may
– ISO Online browsing platform available at https://
require a limited reused powder such that the powder utilized
www.iso.org/obp
for one qualification build to another remains as consistent as
3.3 Definitions:
practical(forexample,byusingvirginfeedstockasthepurpose
3.3.1 build programmer—person responsible for program-
of the qualification is to check the consistency of machine
ming a build including part orientation, part(s) nesting, and the
operation over time).
application of critical build parameters.
5.4.1 A feedstock material specification shall include, but
3.3.2 machine operator—person responsible for initiating not be limited to, chemical composition, particle size
builds and turning over machines, which includes, but is not
distribution, and manufacturing methodology.
limited to, loading feedstock powder, loading build platforms,
5.5 Powder shall be stored in environmental containment to
removing completed builds and routine machine cleaning and
prevent contamination and moisture absorption.
filter changes.
5.6 Used powder is allowed (see 7.1.1.4.1 for requirement
3.3.3 recoater blade—portion of the machine that comes in
on used powder that is processed with ceramic recoater
contact with and spreads feedstock across the build area.
blade).The proportion of virgin to used powder shall be
3.3.3.1 Discussion—Therecoaterblademayalsobecalleda
recorded and reported for each production run on the manu-
rake, recoater, roller, or brush.
facturing plan (Section 10). Automated powder feed systems
may not allow the proportion of virgin to used powder to be
4. PBF Material Identification
accurately measured and recorded on the manufacturing plan.
4.1 Material covered by this document (that is, powder and
Insuchsystemsthefeedstockshallbeconsideredusedpowder.
consolidated part/PBF machine input and output), shall be
The maximum number of times that used powder can be
identifiedbyspecificationcalloutsincluding,butnotlimitedto,
consumed as well as the number of times any portion of a
the following:
powder lot can be processed in the build chamber shall be
4.1.1 Alloy designation according to requirements; where
validated in accordance with 7.3. After a build cycle, any
no alloy designation exists, the chemical composition shall be
remaining used powder may be blended with virgin powder to
listed.
maintain a powder quantity large enough for the next build
4.1.2 Powder type—Virgin, used, blend or mix.
cycle.Thecriticalpowderattributesimpactingqualificationsin
4.1.3 Surface finish—As built, media blasted, supports re-
accordance with 7.3 shall be analyzed regularly. All used
moved by machining or manual deburring, in accordance with
powder shall be sieved with a sieve having a mesh size
specification callouts, or any combination of the latter finish
appropriate for removing any agglomerations. All powder
types.
sieves used to manufacture parts shall have a certificate of
4.1.4 Dimensional tolerances—In accordance with specifi-
conformance that they were manufactured to ISO 9044 or
cation callouts or PBF machine output capability.
Specification E11.
NOTE 1—4.1.3 and 4.1.4 apply to consolidated parts only.
6. Personnel Requirements
6.1 Personnel competency requirements in ISO 13485 shall
5. Feedstock and Powder Batches
apply, including appropriate education, training, skills, and
5.1 The material supplier shall package the powder in
experience.
containers capable of preventing moisture from penetrating the
containers. No other materials including desiccant bags, labels, 6.2 Manufacturing manager, machine operator, or build
programmer (as defined in Section 3) shall be trained by the
or tags shall be placed inside the containers in contact with the
powder. machine manufacturer or qualified agency for PBF machine
hardware and software, where appropriate.
5.2 All feedstock shall have a certificate of conformance
from the material supplier indicating that the feedstock meets 6.3 On machines that are qualified in accordance with 7.3,
the machine manufacturer shall provide for continuing educa-
the purchase specification requirements.
tion as new hardware and software releases are purchased and
implemented. Records of such training shall be maintained in
5
employee training folders in accordance with a local Quality
Available from SAE International (SAE), 400 Commonwealth Dr.,Warrendale,
PA 15096, http://www.sae.org. Management System (for example, ISO 9001, ISO 13485,
© ISO/ASTM International 2019 – All rights reserved
2

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oSIST prEN ISO/ASTM 52904:2020
ISO/ASTM 52904:2019(E)
F3303 − 2018
Designation: F3303 − 2018
ASQC C1, AS 9100) for reference with customers or outside 7.1.1.8 External gas—Gas type and flow shall meet the
regulatory agencies, or both. machine manufacturer’s recommendation for the feedstock.
7.1.1.9 Feedstock and baseline machine and process
6.4 Only persons trained in accordance with 6.1 and 6.2
parameters—Ensure that feedstock and parameters (for
shall be considered qualified personnel.
example, beam offset, beam parameters, input energy) are
correct for build.
7. Qualification
7.1.1.10 Beam power verification—The instructions for
7.1 Pre-Build Checks
checking the laser or electron beam power shall be determined
7.1.1 This section describes pre-build checks applied to all
by the component manufacturer and recorded in a QMS
builds independently of their purpose (for example, periodic
document. Laser or electron beam power shall be measured
preventive maintenance, machine/process qualification,
and documented in the manufacturing plan immediately prior
scaling/calibration builds, etc.). The pre-build checks shall
to build initiation and following the completion of all builds.
include, but not be limited to:
7.1.1.11 Part files, orientation and location—All part files
7.1.1.1 Maintenance record—Checkthemaintenancerecord
related to the digital geometry (for example, STL, AMF) shall
(see 7.2.2) and qualification status of machine (see 7.3).
match the intended revision, the part orientation and location
7.1.1.2 Required feedstock quantity—Verify that required
on the build platform, as stated in the manufacturing plan.
quantity for build is available.
7.1.1.12 Machining stock—Ensure that machining stock is
7.1.1.3 Build platform (also known as build plate or start
added to part(s) in accordance with manufacturing plan.
plate)—Ensure that the build platform serial number matches
7.1.1.13 Parts nesting—The build platform part nesting, as
the one specified in the manufacturing plan (Section 10). The
displayed by the PBF build processor software, shall be
build platform shall be free from any surface contamination
recorded (for example with a screen shot).
(including dirt, oil, or grease), and any form of defects
7.2 Periodic Preventive Maintenance (Third Party Accredi-
resulting in an inconsistent powder bed. Build platforms shall
tation)
be visually inspected and rejected for any obvious damage or
7.2.1 PBF machines shall undergo preventive maintenance
non-conformity. Platform shall be installed in PBF machine
(PM) by trained technicians in accordance with the machine
using the proper QMS instructions.
manufacturer’s recommended frequency (for example, mini-
7.1.1.4 Recoater blade—Ensure material compatibility with
mum of every six months or after a given number of build
feedstock and consolidated material, cleanliness, absence of
hours). PBF machines where preventive maintenance has
any form of defects resulting in an inconsistent powder bed,
lapsed shall not be used to meet the requirements herein. The
and consistent recoater clearance to the build platform at all
maintenance procedure shall confirm the effective function and
locations in conjunction with 10.1.2.2.
operations of each major machine and machine component that
7.1.1.4.1 Before initiating a PBF machine build, the recoater
affects product quality. This shall include, but not be limited to:
blade shall be inspected. The machine operator shall visually
7.2.1.1 Laser or electron beam power—Ensure that beam
inspectandverifythattherecoaterbladeisfreefromanychips,
characteristics are within the machine manufacturer’s recom-
scratches, debris or deformities and installed in accordance
mended tolerance. Test that the laser or electron beam output
with the machine manufacturer’s recommendations. Only
matches software set point in accordance with the machine
qualified materials shall be used on a PBF machine in
manufacturer’s recommendation or specification requirements,
accordance with 7.3.The chemical composition of the recoater
whichever is more demanding. Users of power meters should
blade shall be recorded on the manufacturing plan. PBF
consider the detector calibration uncertainty when measuring
machines with polymer recoater blade shall be validated to
and monitoring laser power. More comprehensive beam quality
show the polymer does not contaminate the feedstock by
measurements may be imposed on the machine vendor for
analyzing and pairing the chemical composition of powder
machine acceptance, for example, switch on/off speed, power
feedstock and that of consolidated part.When inspection is not
fluctuations after hours of operation, and beam
...

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