EN ISO/ASTM 52931:2023

SLOVENSKI STANDARD
01-maj-2023
Dodajalna izdelava kovinskih izdelkov - Okolje, zdravje in varnost - Splošna načela
za uporabo kovinskih materialov (ISO/ASTM 52931:2023)
Additive manufacturing of metals - Environment, health and safety - General principles
for use of metallic materials (ISO/ASTM 52931:2023)
Additive Fertigung von Metallen - Umweltschutz, Gesundheit und Sicherheit - Allgemeine
Grundsätze für die Verwendung metallischer Materialien (ISO/ASTM 52931:2023)
Fabrication additive de métaux - Environnement, santé et sécurité - Principes généraux
pour l’utilisation de matériaux métalliques (ISO/ASTM 52931:2023)
Ta slovenski standard je istoveten z: EN ISO/ASTM 52931:2023
ICS:
13.020.01 Okolje in varstvo okolja na Environment and
splošno environmental protection in
general
13.030.30 Posebni odpadki Special wastes
13.100 Varnost pri delu. Industrijska Occupational safety.
higiena Industrial hygiene
25.030 3D-tiskanje Additive manufacturing
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO/ASTM 52931
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2023
EUROPÄISCHE NORM
ICS 13.020.01; 13.030.30; 13.100; 25.030
English Version
Additive manufacturing of metals - Environment, health
and safety - General principles for use of metallic materials
(ISO/ASTM 52931:2023)
Fabrication additive de métaux - Environnement, santé Additive Fertigung von Metallen - Umweltschutz,
et sécurité - Principes généraux pour l'utilisation de Gesundheit und Sicherheit - Allgemeine Grundsätze für
matériaux métalliques (ISO/ASTM 52931:2023) die Verwendung metallischer Materialien (ISO/ASTM
52931:2023)
This European Standard was approved by CEN on 22 January 2023.

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, Türkiye 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
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO/ASTM 52931:2023 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO/ASTM 52931:2023) has been prepared by Technical Committee ISO/TC 261
"Additive manufacturing" in collaboration with 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 August 2023, and conflicting national standards shall
be withdrawn at the latest by August 2023.
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.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
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, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO/ASTM 52931:2023 has been approved by CEN as EN ISO/ASTM 52931:2023 without
any modification.
INTERNATIONAL ISO/ASTM
STANDARD 52931
First edition
2023-01
Additive manufacturing of metals —
Environment, health and safety —
General principles for use of metallic
materials
Fabrication additive de métaux — Environnement, santé et sécurité
— Principes généraux pour l’utilisation de matériaux métalliques
Reference number
ISO/ASTM 52931:2023(E)
© ISO/ASTM International 2023
ISO/ASTM 52931:2023(E)
© ISO/ASTM International 2023
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: +610 832 9635
Email: copyright@iso.org Email: khooper@astm.org
Website: www.iso.org Website: www.astm.org
Published in Switzerland
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ISO/ASTM 52931:2023(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviations . 1
5 Methodology .2
5.1 General . 2
5.2 Chemical hazard methodology . 4
6 Source data. 4
6.1 General . 4
6.2 Input products and by-products . 4
6.2.1 Safety data sheet . 4
6.2.2 Product technical datasheet . 5
6.3 Process . 5
6.3.1 General . 5
6.3.2 Means of storage and implementation . 5
6.4 Feedback from experience . 5
6.4.1 Incident reports . . 5
6.4.2 Technical and normative watch . 6
6.4.3 Measurement reports and analyses . 6
7 Risk assessment . 6
7.1 Identification of hazards . 6
7.2 Documentation on hazards . 6
7.2.1 General . 6
7.2.2 Identification of hazards related to inputs . 7
7.2.3 Hazards related to substances generated during additive manufacturing . 11
7.2.4 Hazards related to fire and explosion . 11
7.3 Identification of exposing situations . 11
7.4 Characterization and risk rating . 15
7.4.1 General .15
7.4.2 Rating of risks related to contamination, inhalation or skin contact .15
7.4.3 Rating the risks related to explosion . 16
8 Prevention and protective measures.17
8.1 General . 17
8.2 Workplaces . . . 17
8.2.1 Floors and walls . 17
8.2.2 Air flow rate . 18
8.2.3 Fire . 18
8.2.4 Electric . 19
8.2.5 Powder storage . 19
8.2.6 Best practices for workplaces for personnel . 20
8.3 Process . 20
8.4 Organization . 20
8.4.1 General .20
8.4.2 Training of personnel . 21
8.4.3 Information for personnel . 21
8.4.4 Limitation of exposed personnel . 21
8.4.5 Reduction of exposure. 21
8.4.6 Personal protective equipment . 22
8.5 Waste management . 23
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ISO/ASTM 52931:2023(E)
8.5.1 General .23
8.5.2 Contaminated filters . 24
8.5.3 Waste from immersion vacuums and cleaning systems . 24
8.5.4 General dry powder waste . 24
Annex A (informative) Safety data sheet .25
Annex B (informative) Definition of limit values .27
Annex C (informative) Hazards related to fire and explosion.28
Annex D (informative) Overview of OEL for substances.30
Bibliography .34
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ISO/ASTM 52931:2023(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. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO 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.
The committee responsible for this document is ISO/TC 261, Additive manufacturing, in cooperation with
ASTM Committee F42, Additive manufacturing technologies, on the basis of a partnership agreement
between ISO and ASTM International with the aim to create a common set of ISO/ASTM standards
on additive manufacturing, in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 438, Additive manufacturing, in accordance with the Agreement on
technical cooperation between ISO and CEN (Vienna Agreement).
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.
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ISO/ASTM 52931:2023(E)
Introduction
The use of additive manufacturing (AM) processes with metallic feedstock entails a number of hazards.
It is therefore important, as a first step, to implement a high level of protection during manufacturing
and installation of the additive manufacturing machine or system. For this purpose, ISO/ASTM 52938-1
dealing with safety of PBF-LB machines is under preparation.
In addition, the users of additive manufacturing plants have the duty to reduce the risks for the operators
remaining after installation so that they fulfil the nationally or regionally pertinent regulations for
health and safety at work. The latter are very different worldwide and the requirements of a standard
cannot fully reflect them. For users of additive manufacturing plants, the guidelines and requirements
of this document are, therefore, particularly relevant with regard to aspects not sufficiently covered by
pertinent national or regional regulations for safety and health at work.
vi
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INTERNATIONAL STANDARD ISO/ASTM 52931:2023(E)
Additive manufacturing of metals — Environment, health
and safety — General principles for use of metallic
materials
1 Scope
This document provides guidance and requirements for risk assessment and implementation of
prevention and protection measures relating to additive manufacturing with metallic powders.
The risks covered by this document concern all sub-processes composing the manufacturing process,
including the management of waste.
This document does not specify requirements for the design of machinery and equipment used for
additive manufacturing.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 11611, Protective clothing for use in welding and allied processes
ISO 16321-1, Eye and face protection for occupational use — Part 1: General requirements
ISO 16321-3, Eye and face protection for occupational use — Part 3: Additional requirements for mesh
protectors
ISO/ASTM 52900, Additive manufacturing — General principles — Fundamentals and vocabulary
ISO/ASTM 52907:2019, Additive manufacturing — Feedstock materials — Methods to characterize metal
powders
IEC 60079-10-1, Explosive atmospheres — Part 10-1: Classification of areas — Explosive gas atmospheres
IEC 60079-10-2, Explosive atmospheres — Part 10-2: classification of areas — Combustible dust
atmospheres
ANSI Z87.1, Practice for Occupational and Educational Eye and Face Protection
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/ASTM 52900 apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Abbreviations
The abbreviations and acronyms used in this document are listed in Table 1.
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ISO/ASTM 52931:2023(E)
Table 1 — Abbreviations and acronyms
Abbreviation Signification
ACGIH American Conference of Governmental Industrial Hygienists
AHU air handling unit
ATEX atmospheres explosives
CLP classification, labelling, packaging
CMR carcinogenic, mutagenic or reprotoxic
EChA European Chemicals Agency
EHS environmental health and safety
GHS globally harmonized system
MSD musculo skeletal disorder
NIOSH National Institute for Occupational Safety and Health
OEL occupational exposure limit
OSHA Occupational Safety and Health Administration
PPE personal protective equipment
REACh registration, evaluation and authorisation of chemicals
SDS safety data sheet
UNECE United Nations Economic Commission for Europe
5 Methodology
5.1 General
The method described in this document allows the user to assess the EHS risk considering the following:
— metallic powders used;
— AM process;
— AM system installation conditions;
— applicable good practices;
— feedback from experience.
The methodology is based on a characterization of physical hazards (e.g. fire and explosion), hazards to
the health of the operator or the potentially exposed third parties and to the environment. The overall
approach to risk assessment and implementation of prevention measures is illustrated in Figure 1 and
detailed in Table 2.
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ISO/ASTM 52931:2023(E)
Figure 1 — Overall approach to risk assessment and implementation of prevention measures
Table 2 — Content of the steps toward the evaluation and prevention of risks
Aspects taken into
Main steps Factors/measures
account
Safety data sheets, products implemented with
Input products and
classification, toxicity and granulometry, Instruction
by-products
handbooks, Current regulations
Source data Means (premises and work equipment) implemented
Process
for the storage, transport and processing of inputs
Measurement, analysis, medical follow-up, incident
Feedback from experience
reports, supervision of technology and regulation
Identification of the inherent hazards of the inputs
Identification of hazards and by-products generated at the different stages of
the process and the exposing situations
Identification of tasks and activities with potential
Risk assessment Identification of exposing
for exposures at the different stages of the process
situations
including accidental exposure
Characterization and risk Characterization and rating of the risks to health,
rating safety and environment
Layout, performance of containment, airflow/venti-
Workplace
lation, air monitoring function
Feedstock, work equipment, capture performance,
sealing, filtration cleanliness, level of reliability of
Process
detection functions, controls, category of risks relat-
Verification of organizational
ed to explosion.
measures
Procedures, process flow, level of training, PPE,
Organization medical follow-up, monitoring of premises and
equipment
Waste collection, storage and disposal. Spill preven-
Waste management
tion and containment
Tests and validation of Sampling, atmospheric dosimetry, surface measure-
preventive measures ments, adequacy audit
Verification of prevention
and protection measures
Registration of initial Ambient measurement
state
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ISO/ASTM 52931:2023(E)
TTabablele 2 2 ((ccoonnttiinnueuedd))
Aspects taken into
Main steps Factors/measures
account
Monitoring and management of workplace/process/
Monitoring of the produc- organization modification, regulatory and techno-
Supervision
tion process logical monitoring, Sampling, atmospheric dosime-
try, area of surface contamination
5.2 Chemical hazard methodology
The steps for assessing and controlling the risk of exposure to hazardous chemical agents are described
in Figure 2:
Figure 2 — Main steps of a chemical risks prevention process
6 Source data
6.1 General
Applicable local regulations should be considered (see Directive 89/391/EEC in Europe and OSHA in
USA).
6.2 Input products and by-products
6.2.1 Safety data sheet
See information given in Annex A.
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ISO/ASTM 52931:2023(E)
6.2.2 Product technical datasheet
The product technical datasheet should also contain information about particle size distribution.
Technical specification of metal powders shall be provided in accordance with ISO/ASTM 52907:2019,
Annex A.
6.3 Process
6.3.1 General
The instructions for proper installation, use and maintenance of the AM equipment and post
processing equipment shall be followed. The user should ensure that the combination of feedstock and
AM equipment and post processing equipment has been taken into account. The user shall perform
a specific risk assessment, preferably with the support of the AM equipment and post processing
equipment manufacturer and of the supplier of the feedstock(s).
6.3.2 Means of storage and implementation
For the regular use of metallic powders, national regulations and organisational policies related
to hazardous substances should be observed. This would include registering of the material in the
organization and risk assessments for the individual processes performed with the material based on
information from the safety data sheets. This would provide hierarchical control for the following, as a
minimum:
— powder identification;
— storage location;
— storage requirements (legal aspects, safety aspects and powder quality aspects);
— manual handling requirements;
— maximum volume/s of powder for each process;
— use of ancillary equipment (wet separators, sieving units, etc.),
— housekeeping requirements;
— PPE requirements.
6.4 Feedback from experience
6.4.1 Incident reports
When an incident occurs for an operator of a facility, the company should provide a report analysing
the causes of the incident, its effects and consequences on people and the environment. The description
useful for in the incident report is:
— description of the process and its equipment: implementation, products involved, operating
conditions in normal operation, procedures, rules, control operations, maintenance, cleaning, etc.;
— safety measures (prevention, protection), procedures, qualifications, training;
— circumstances, context and chronology of the incident:
— operating context before and during the incident, product condition, identification of deviations
from normal, testimonials, latest interventions (maintenance, control, inspections, interviews,
work, other incidents.);
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ISO/ASTM 52931:2023(E)
— chronology of events and incident management (interveners present, actions carried out, date/
time,.);
— miscellaneous findings;
— characterization of the consequences:
— experimental characterization to remove doubts (measurement, incident reproduction, product
characterization);
— characterization by modelling (e.g. fire in an AM workplace);
— recommendations: prevention, detection, protection, management of activities.
6.4.2 Technical and normative watch
Technical and/or normative documents should be available, reviewed and the AM process updated as
needed as soon as practicable after publication.
6.4.3 Measurement reports and analyses
All emission measurements, either on receipt of the equipment or in normal operation, as well as the
history of exposure measurements are useful feedback for risk assessment or re-assessment.
If the risk assessment shows that there is at least one exposure situation subject to a regulatory OEL,
exposure levels shall be controlled in accordance with the regulations.
NOTE Currently, there are no known common cases in the field of AM with metallic materials requiring the
intervention of an accredited body, but this cannot be excluded.
7 Risk assessment
7.1 Identification of hazards
All dangerous chemicals and materials shall be identified. The prevention approach consists in
systematically identifying the presence of such products and any working situation in which operators
and other personnel could be exposed.
NOTE Reactive and non-reactive powders have different handling and storage requirements. Refer to safety
data sheet (SDS) for these requirements.
7.2 Documentation on hazards
7.2.1 General
For AM workspaces and feedstock storage locations the use of chemical safety cards (CSC) is strongly
recommended, and depending on local regulations, mandatory. Chemical safety cards provide the
essential health and safety information of chemicals in a clear and concise manner. This includes
information on hazards, required PPE and actions to be taken in the event of an accident or spill.
Chemical safety cards are available for pure substances only in the database mentioned in the note
below. For alloys and mixtures, it is recommended that the employer composes a similar document
based on the information provided in the safety data sheet (SDS) and structured in a similar way as a
chemical safety card.
NOTE An extensive database of ready to use cards has been composed in the International Chemical Safety
Cards (ICSC) project. This project is a collaboration between International Labour Organization (ILO) and the
World Health Organization (WHO), with the cooperation of the European Commission. For more information see
the following references:
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ISO/ASTM 52931:2023(E)
https:// www .ilo .org/ dyn/ icsc/ showcard .home
https:// www .who .int/ publications/ m/ item/ international -chemical -safety -cards -leaflet
https:// www .cdc .gov/ niosh/ ipcs/ default .html
7.2.2 Identification of hazards related to inputs
7.2.2.1 General
The following requirements shall be satisfied, in order to identify the hazards related to handling metal
alloys in powder:
— consider the regulatory requirements that are relevant to the production and use site;
— identify the hazards related to each metallic element in the alloy and by alloy family.
A guidance for understanding safety data sheets (SDSs) is given in Annex A.
Users should regularly check for the latest available updates of the SDS.
7.2.2.2 Identification of dangerous products
The classification information included in the safety data sheets sent by the supplier shall be taken into
account. The safety data sheets shall be written in the language of the recipient country and accompany
each product.
NOTE 1 In European countries, classification information is available in the classification, labelling and
packaging regulation. For the other countries, it is suitable to refer to the national regulations or by default to the
GHS regulation.
Within the European Union, the CLP regulation gives the classification applicable to chemicals. They
are classified into the following 3 families:
— substances (unitary chemical elements: aluminium, iron, titanium, etc.);
— mixtures (in the form of raw materials: free powder, alloys, etc.);
— articles (semi-finished products and finished products: bars, sheets, manufactured products, etc.).
— For alloys, only in lack of specific data, the hazard shall be rated as the sum of the hazards of the
substances, using the classification rules.
NOTE 2 Classification, labelling and packaging regulation of substances that are accessible and up to date
on the website of EChA make it possible to check whether Section 2 of the manufacturer's safety data sheet
conforms. see the following:
https:// echa .europa .eu/ fr/ information -on -chemicals/ cl -inventory -database
NOTE 3 Two sources exist for establishing the classification:
— EU member countries; this classification is said to be “harmonized”;
— manufacturers who generally come together into consortiums; this classification is said to be “joint
submission”;
— REACh files has increased the numbers coming under this second classification.
NOTE 4 The GHS system of classification and labelling of chemicals is an international initiative under the
guidance of UNECE. Parallel to GHS UNECE is also involved in the composition of guidelines concerning the safe
transport of chemicals.
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ISO/ASTM 52931:2023(E)
NOTE 5 While UNECE does not compose legislation, it is the intention to translate the suggested guidelines
by UNECE into the local regulatory and legal framework of the governments involved. A list of participating
countries and the status of the implementation in those countries can be found on the UNECE website. This
includes links to the local governmental bodies and ratified texts.
https:// www .unece .org/ trans/ danger/ publi/ ghs/ implementation _e .html
NOTE 6 While in this document the term GHS is used freely understanding that the GHS guidelines are, or are
to be, implemented worldwide, it is up to the reader to check the status of the local implementation.
7.2.2.3 Hazards related to the nature of products
Hazards are identified in Section 2 of the safety data sheet. The user shall take this into account.
The chemical risk depends on the hazard (see Table 4) and on the exposure. The exposure to chemical
substances can occur mainly via three modes of penetration which are inhalation, skin contact, and
ingestion.
Generally, the main routes for occupational exposure to metals are inhalation (especially in powder
form) as well as skin contact (for powders as well as for wires).
NOTE 1 OELs for dermal exposure are lacking and it is the responsibility of the user to decide on skin
contamination criteria. Resources exist such as:
— NIOSH skin notations: https:// www .cdc .gov/ niosh/ topics/ skin/ skin -notation _profiles .html;
— ACGIH provides skin and sens notations if applicable for metals.
NOTE 2 For Europe, some information can be found in REACh and EChA.
Alloys shall in general be considered as substances. Only in lack of sufficient data for an alloy, for each
metal element of an alloy, an exposure assessment shall be conducted in order to establish a reference
for the chemical risk related to exposure by inhalation.
NOTE 3 These data are indicated in Section 8 of the safety data sheet (See Annex A).
The relevant national regulations take precedence over any other reference. However, when there is no
OEL in the applicable regulations, or when a significant difference exists related to more recent limit
values, it is recommended to choose a reference that is more stringent than the applicable regulations.
For all particles or dust not having any specific effect, the OEL is as follows:
— 10 mg/m for the total fraction;
— 5 mg/m for the breathable, respirable fraction or alveolar fraction.
A substance that is not classified in the classification, labelling and packaging regulation and that has an
occupational exposure limit value identical to one of those references is not a substance with a specific
chemical risk. Those references are therefore not indicators or drivers of the toxicity of an alloy powder.
NOTE 4 The “breathable fraction”, “alveolar fraction” or “respirable fraction” is the effective inhaled fraction
that reaches the pulmonary alveoli, where the majority of it can penetrate into the person's system.
NOTE 5 There is a European database, GESTIS, which gives the OEL values for various countries available at:
https:// www .dguv .de/ ifa/ gestis/ gestis -internationale -grenzwerte -fuer -chemische -substanzen -limit -values -for
-chemical -agents/ index -2 .jsp.
The European regulations are being drafted and certain new stringent occupational exposure limit
values can be set.
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ISO/ASTM 52931:2023(E)
7.2.2.4 Hazards related to particle size distribution
The particle size distribution is an important parameter to consider in prevention. A high concentration
of fine particles generates health risks due to the physical nature of the particles (see Table 3).
Table 3 — Effects of particles on health depending on particle size distribution
a b
Particle diameter Effects
less than 100 μm All particles less than 100 μm can easily enter the nasal cavities
Trapped by impact in the nasal cavity, the pharynx, and the larynx
between 5 μm and 100 μm
Cannot keep up with the sudden changes of direction and collide with the
walls or hairs
Most of them are deposited by sedimentation in the trachea, the bronchi, and
between 1 μm and 5 μm
the bronchioles
less than 1 µm Reach the alveoli
a
In some context particle aerodynamic diameter as defined in ISO 18158 could be of concern.
b
Can cause immunological and inflammatory reactions.
NOTE See EN 481 for details of the respective definition of size fractions.
CAUTION — The size of the particles is not indicated in the SDS and It is nevertheless essential to
take it into account. The size of unused feedstock powder particles stated by a manufacturer on a
technical specification sheet or other document may not be indicative of the size of particles that
can be released during handling, printing, or other tasks. Any risk related to powder particle
size shall be taken into account.
7.2.2.5 Hazards identified per substance
A non-exhaustive list of OELs identified according to the substances (compound and oxidized forms) is
given in Annex D.
7.2.2.6 Hazards identified per family of alloys
The hazards identified per family of alloys are listed in Table 4.
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ISO/ASTM 52931:2023(E)
© ISO/ASTM International 2023 – All rights reserved

Table 4 — Hazards per family of alloys
Alloy containing 1 Alloy not contain-
Flammabiltiy and/
Base Alloys Family substances or more CMR sub- ing CMR substance-
or explosion risk
a bc
stance
Al AlSi and derivates Al, Si, Mg, Ti Yes Ti others
superalloy: H188, Inconel 783, … Co, Al, B, C, Cr, Fe, La, Nb, Ni, Si, Ti, W SDS to be checked Cr, Co, Ni, Ti others
Co stellite 6, 12, 21, … Co C, Cr, Mo, Ni, W SDS to be checked Co, Cr, Ni others
CoCr and derivates Co, Cr, Mo, V SDS to be checked Cr, Co, V others
CuCr1Zr Cu, Cr, Zr SDS to be checked Cr others
Cu
CuNi2CrSi (CuNi2) Cu, Ni, Cr, Si SDS to be checked Ni, Cr others
Stainless steel: 316L, 420, … Fe, Cr, Mo, Mn, Nb, Ni, SDS to be checked Cr, Ni others
Precipitation Hardening Stainless Steels: Fe, Ni, Cr, Mo, Cu, C Cr, Ni others
Fe SDS to be checked
15–5PH, 17–4PH, …
Maraging steel: 1,270 9, … Fe, Ni, Co, Mo, Ti, Al, C SDS to be checked Co, Ni, Ti others
Structural hardening: Hastelloy, Inconel 625, … Ni, C, Co, Cr, Fe, Mo, Nb, W SDS to be checked Cr, Co, Ni others
Precipitation hardening Ni, Al, B, Co, Cr, Fe, Mo, Nb, Ta, Ti, W SDS to be checked Cr, Co, Ni, Ti others
Ni
Inconel 718, waspaloy, …
Pure Nickel: Ni200, Ni201, … Ni SDS to be checked Ni
Ti alloys Al, Mo, Sn, Si, V, Zr Yes Ti, V others
Ti
TiAl and derivates B, Al, Nb, Mo Yes Ti others
a
Substances presenting CMR-risk or suspect to present CMR risk.
b
Substances not presenting CMR risk.
c
The bio accessibility of the substances do not linearly correspond to the content in the alloy.
NOTE This table is not complete. e.g. non-metallic substances as parts of the alloys are not contained. In these cases, the safety data sheet contains relevant information.

ISO/ASTM 52931:2023(E)
7.2.3 Hazards related to substances generated during additive manufacturing
Substances generated dur
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