Safety of machinery - Ionizing radiation emited by machinery - Guidance for the application of technical standards in the design of machinery in order to comply with legislative requirements

The purpose of this report is to give guidance on:
a) how to comply with the relevant legislative requirements, and
b) how to take into account the technical recommendations specified in International, European and National Standards when machines emitting ionizing radiation are designed and built.

Sicherheit von Maschinen - Von Maschinen emittierte ionisierende Strahlung - Leitfaden zur Anwendung vontechnischen Normen bei der Konstruktion von Maschinen um den gesetzlichen Anforderungen zu entsprechen

Sécurité des machines - Rayonnements ionisants émis par les machines - Guide pour l'application des normes techniques dans la conception des machines afin de satisfaire aux exigences réglementaires

Le présent rapport donne des recommandations permettant, lors du processus de conception et de construction des machines émettant des rayonnements ionisants :
a) de s'assurer de la conformité aux exigences réglementaires applicables ;
b) de prendre en compte les prescriptions techniques contenues dans les différentes normes internationales, européennes ou nationales en vigueur.

Varnost strojev - Ionizirno sevanje, ki ga oddajajo stroji - Navodilo za uporabo tehničnih standardov pri oblikovanju strojev v skladu z zakonodajnimi zahtevami

General Information

Status
Published
Publication Date
08-Jun-2004
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Due Date
09-Jun-2004
Completion Date
09-Jun-2004

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SLOVENSKI STANDARD
SIST CEN/TR 14715:2004
01-september-2004
9DUQRVWVWURMHY,RQL]LUQRVHYDQMHNLJDRGGDMDMRVWURML1DYRGLOR]DXSRUDER
WHKQLþQLKVWDQGDUGRYSULREOLNRYDQMXVWURMHYYVNODGX]]DNRQRGDMQLPL]DKWHYDPL
Safety of machinery - Ionizing radiation emited by machinery - Guidance for the

application of technical standards in the design of machinery in order to comply with

legislative requirements

Sicherheit von Maschinen - Von Maschinen emittierte ionisierende Strahlung - Leitfaden

zur Anwendung vontechnischen Normen bei der Konstruktion von Maschinen um den
gesetzlichen Anforderungen zu entsprechen

Sécurité des machines - Rayonnements ionisants émis par les machines - Guide pour

l'application des normes techniques dans la conception des machines afin de satisfaire

aux exigences réglementaires
Ta slovenski standard je istoveten z: CEN/TR 14715:2004
ICS:
13.110 Varnost strojev Safety of machinery
13.280 Varstvo pred sevanjem Radiation protection
SIST CEN/TR 14715:2004 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST CEN/TR 14715:2004
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SIST CEN/TR 14715:2004
TECHNICAL REPORT
CEN/TR 14715
RAPPORT TECHNIQUE
TECHNISCHER BERICHT
June 2004
ICS 13.220.10
English version
Safety of machinery - Ionizing radiation emited by machinery -
Guidance for the application of technical standards in the design
of machinery in order to comply with legislative requirements

Sécurité des machines - Rayonnements ionisants émis par Sicherheit von Maschinen - Von Maschinen emittierte

les machines - Guide pour l'application des normes ionisierende Strahlung - Leitfaden zur Anwendung von

techniques dans la conception des machines afin de technischen Normen bei der Konstruktion von Maschinen

satisfaire aux exigences réglementaires um den gesetzlichen Anforderungen zu entsprechen

This Technical Report was approved by CEN on 3 November 2003. It has been drawn up by the Technical Committee CEN/TC 114.

CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,

Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,

Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels

© 2004 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 14715:2004: E

worldwide for CEN national Members.
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Contents

1 Scope ..............................................................................................................................................................4

2 Relevant legislation .......................................................................................................................................4

2.1 European Directives ......................................................................................................................................4

2.1.1 Machinery Directive 98/37/EC (Currently under revision) .........................................................................4

2.1.2 Directive 96/29/EURATOM on Basic Safety Standards for the protection of the health of

workers and the general public against the dangers arising from ionizing radiation............................4

2.2 National Legislation.......................................................................................................................................5

3 Standard Technical Specifications ..............................................................................................................6

4 Other Sources of Information.......................................................................................................................6

5 Methodology for compliance with Machinery Directive - Radiation.........................................................6

5.1 General............................................................................................................................................................6

5.2 Full compliance with ESR .............................................................................................................................7

5.3 Alternative approach to compliance with ESR ...........................................................................................7

5.3.1 General............................................................................................................................................................7

5.3.2 Reduction of emission levels .......................................................................................................................7

5.3.3 Methods for limiting the access to irradiated area.....................................................................................8

5.3.4 Further actions...............................................................................................................................................9

6 Measurement of Radiation Emissions.........................................................................................................9

7 Instructions for Use .......................................................................................................................................9

Annex A (informative) Examples of technical standards relating to ionizing radiation emissions from

machinery .....................................................................................................................................................10

A.1 Type C Standards relating to machines that may emit ionizing radiation.............................................10

A.2 Type B Standards on shielding properties of materials against ionizing radiation .............................15

A.3 Type B Standards relating to measurement of ionizing radiation emissions .......................................16

Annex B (informative) Examples of documents published by International, European and national

organisations................................................................................................................................................26

Bibliography ..............................................................................................................................................................27

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Foreword

This document CEN/TR 14715:2004 has been prepared by Technical Committee CEN/TC 114 “Safety of

machinery”, the secretariat of which is held by DIN.
Annexes A and B are informative.

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following

countries are bound to announce this Technical Report: Austria, Belgium, Cyprus, Czech Republic, Denmark,

Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,

Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom

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Introduction

Machines may emit ionizing radiation either from incorporated radioactive sources or high voltage accelerators (e.g.

X-ray machines). Exposure of people to ionizing radiation staying close to the machinery may present a risk to

health. To control these health risks, requirements are specified in European and National legislation. The

legislation that regulates the design, manufacture and supply of machines is the European Machinery Directive,

(98/37/EC). Systems for the protection of workers against the effects of ionizing radiation are specified in a

EURATOM Directive (96/29/EURATOM). Detailed technical features are set out in international, European and

national standards.
1 Scope
The purpose of this report is to give guidance on:
a) how to comply with the relevant legislative requirements, and

b) how to take into account the technical recommendations specified in International, European and National

Standards
when machines emitting ionizing radiation are designed and built.
2 Relevant legislation
2.1 European Directives
2.1.1 Machinery Directive 98/37/EC (Currently under revision)

One of the purposes of this Directive is to provide a uniform approach to maintaining or improving the level of

safety design of machinery. The Annex 1 to the Machinery Directive lists all the essential health and safety

requirements (ESRs) relating to the design and construction of machinery. Of these, ESR 1.5.10 for 'Radiation'

states:

"Machinery must be so designed and constructed that any emission of (Proposed amendment specifies both

ionizing and non-ionizing, Revision COM (2000) 899 final 2001-01-26) radiation is limited to the extent necessary

for its operation and that the effects on exposed persons are non-existent or reduced to non-dangerous

proportions."

This document gives guidance on how to comply with ESR 1.5.10 or, if it is not possible during the design or

building stage to reduce the emission levels to non-dangerous proportions, how to proceed in order to fulfil the

Machinery Directive.

When considering ionizing radiation emissions, there can be no impediment to supply of the machines within the

European Union if the requirements of the ESR 1.5.10 [ESR 1.6.11 in proposed Amendment, Revision COM (2000)

899 final 2001-01-26] have been achieved.

2.1.2 Directive 96/29/EURATOM on Basic Safety Standards for the protection of the health of workers and

the general public against the dangers arising from ionizing radiation

The requirements for the health protection of the general public and workers against the dangers of ionizing

radiation are laid down in Council Directive 96/29/EURATOM. This Directive is based on the principles put forward

by the International Commission for Radiation Protection (ICRP) in their Publication N° 60.

EURATOM Directive contains among others requirements such as:
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a) maximum permissible doses compatible with adequate safety;
b) maximum permissible levels of exposure and contamination;
c) fundamental principles governing the health surveillance of workers.

In addition to the requirements for restricting exposure and dose limitation, the Council Directive 96/29/EURATOM

also make provisions for the appointment of qualified experts, designation of areas and workers, local rules,

monitoring the exposure of employees, medical supervision, notification of work activities, record keeping, etc.

There are also requirements for the investigation of high individual exposures and incidents or accidents involving

significant contamination or releases of radioactive material.

The EURATOM Directive requires potential users of sources of ionizing radiation either to give a prior report of their

intention to the relevant national authority (see article 3 (1) of EURATOM Directive) or to obtain an authorisation

from the national competent authority (see article 4 of EURATOM Directive).

As an exception, for sources considered as safe, article 3 (2) of EURATOM Directive allows the use of radioactive

substances or electrical apparatus emitting ionizing radiation without reporting or authorisation if specified

requirements are fulfilled.
For machines this exception apply if the following conditions are fulfilled:

a) machines containing radioactive sources which do not exceed defined quantities, in terms of activity or mass

activity concentration (see Annex 1 of EURATOM Directive);

b) machines containing radioactive sources exceeding the quantities or concentration values specified in a),

provided that:
1) it is of a type approved by the national competent authority;

2) if the incorporated radioactive source is constructed in the form of a sealed source;

3) it does not cause, in normal operating conditions, a dose rate exceeding 1 μSv.h at a distance of 0,1 m

from any accessible surface of the machine;

4) conditions for disposal have been specified by the national competent authority;

c) operation of machines containing electrical apparatus provided that:
1) it is of a type approved by the national competent authority;

2) it does not cause, in normal operating conditions, a dose rate exceeding 1 μSv.h at a distance of 0,1 m

from any accessible surface of the apparatus.

If a machine complies with one of the requirements specified under a), b) or c) it can be considered that the

machine complies also with the ESR 1.5.10 of Machinery Directive.
2.2 National Legislation

European Directives are directed at the Member States (MS), who have to incorporate the requirements into their

national legislation. National legislation for the design, construction and supply of machines have to contain

identical requirements to those set out in the Machinery Directive. European Directives for the protection of people

(e.g. 96/29/EURATOM) specify minimum requirements which may be more restrictively transcribed into national

legislation to provide a higher level of protection. Therefore users of machines emitting ionizing radiation will not

only have to comply with the national legislation arising from European Directives but also with any increased

national requirements to protect people.
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3 Standard Technical Specifications

International, European and National Standards may give useful background material for designers, manufacturers

and users of machines emitting ionizing radiation. Standards may also provide technical specifications that are

relevant:
 to the measurement of ionizing radiation emissions;

 to describe techniques or give information on the reduction of emissions from machines;

 to provide data on the shielding properties of various materials.
Examples of such standards are listed in Annex A.
4 Other Sources of Information

It is recognised that there is a large volume of technical information available in the form of technical reports,

recommendations or professional guidelines giving useful background material for designers, manufacturers and

users of machines emitting ionizing radiation.
Organisations preparing such documents are for example:
 International Commission for Radiological Protection (ICRP);
 International Atomic Energy Agency (IAEA);

 Organisation for Economic Co-operation and Development/Nuclear Energy Agency (OECD/NEA);

 American Standard for Testing Material (ASTM);
 National organizations in charge of health and safety.
Some relevant documents published by these organisations are given in Annex B.
5 Methodology for compliance with Machinery Directive - Radiation
5.1 General

Two types of approaches are possible to comply with Machinery Directive requirements:

 a full compliance with all the ESR 1.5.10;

 If not possible, the machinery must be designed and constructed with the purpose of approaching those

objectives (e.g. by using of additional shielding).

NOTE If compliance with ESR 1.5.10 cannot be met, in all EURATOM Directive requires additional protection measures.

These measures, which purposes are to reduce the exposure of people during operation by management or segregation, may

include:
- prohibition of non-essential access to the irradiated areas;
- remote controlled and automatic processes;
- installation of additional shielding by the user at work places;
- use of personal protective equipment;
- limiting time of exposure;
- extending the distances between the machine and the operators.
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5.2 Full compliance with ESR

To achieve the requirement of the ESR, the design of a machine must restrict emissions to a level that is necessary

for the function and that the effects on exposed persons are non-existent or reduced to non-dangerous proportions.

These objectives can be met when a machine complies with one of the requirements specified under a), b) or c) of

2.1.2.

NOTE Machines that comply with the conditions specified in Article 3 of the EURATOM Directive are deemed to comply

with ESR 1.5.10.
Using such type-approved machines may provide advantages to the user:

a) the users will not be required to report to the national authorities their intention to use the machine;

b) type approval requires that the radioactive substances are in the form of sealed sources, thereby reducing the

possibility of releasing contamination;

c) machines that are type approved may be used with less restrictive controls in the workplace because they

present an inherently lower risk to workers and the environment.

To fulfil ESR 1.5.10 manufacturers may need to incorporate features in their products that reduce the emissions

from them. Where a technical specification exists for the design of that type or class of products to reduce

emissions, it should be used.
5.3 Alternative approach to compliance with ESR
5.3.1 General
If the requirements of 5.2 cannot be met, the following measures can be applied:

 reduction of emission levels by selection of suitable radiation source (radioactive source or electrical

accelerator) or by adding shielding around the process area;

 limiting the access to irradiated area by using either additional guards, mechanical shutters, or other means

intended to restrict the exposure of people.
5.3.2 Reduction of emission levels
5.3.2.1 Selection of radiation sources

The selection of radiation sources will need to consider the materials to be processed and the intended lifetime of

the machine. Balancing the following factors will be the decision of the designer, but the overriding objective is to

reduce the emissions to as low as possible while permitting the machine to function as intended.

Factors affecting the choice of radioactive sources will be:
 radionuclide half life;
 emission energy and types (alpha, beta, gamma, neutron);
 activity;
 source design (sealed, according to ISO 2919, see A.1, or unsealed);
 beam geometry (multidirectional or unidirectional);
 safe working life;
 shielding property (effectiveness, weight, volume).
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Factors to be considered when selecting operational settings for electrical accelerators:

 accelerating voltage;
 beam current;
 beam geometry;
 target material;
 shielding property (effectiveness, weight, volume).
5.3.2.2 Shielding

The inclusion of shielding in the machine housing will remove or reduce radiation emissions at accessible points

around the machine. Design of the shielding has to take account of the materials selected and the construction.

Factors to be taken into account when selecting shielding:
 type of radiation;
 attenuation ability;
 radiation energy;
 secondary emissions;
 physical strength, durability, flammability, resistance to radiation damage;
 chemical form and toxicity;
 weight, volume of material.

Examples of standards providing detailed technical information about shielding properties of different materials are

given in A.2.
5.3.2.3 Special considerations regarding joints or openings

Design features such as joints or openings and their covers need special attention. If service penetrations through

the shielding materials cannot be avoided, special design requirements to control radiation leakage are to be

applied (e.g. zigzag channels, additional overlap shielding, etc.).

Other aspects to be considered include interlocking of movable shields, prevention of leaks and uncontrolled

release of radiation, use of enclosed material handling devices, process control systems,

5.3.2.4 Balancing

Source selection and shielding design will need to be balanced when making decisions.

5.3.3 Methods for limiting the access to irradiated area

To restrict exposure of people, the access to the irradiated area shall be limited. In respect to this objective, the

following requirements shall be fulfilled:
 wherever possible, the irradiated area shall be totally enclosed;

 if there is a need for access to the radiation field or beam, then access points should be included in the design.

The construction of access points shall not create leakage of radiation above the emission levels specified in

the design targets;
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 if the process area is not an enclosed volume, barriers, trip devices or guards should be installed to prevent

access to this area or to provide additional radiation attenuation. If these guards are only to prevent human

access, openings shall be forbidden or their surfaces reduced as far as possible. Interlock system are

recommended.
5.3.4 Further actions

The appliance of the previous additional protective measures shall lead to the following conclusion:

 the remaining emission levels do not exceed 1 μSv.h at a distance of 0,1 m from any accessible surface. In

this case, instructions of use shall contain guidance for complying with additional requirements specified by

EURATOM Directive (e.g. reporting, authorisation, source disposal);

 the remaining emission levels exceed 1 μSv.h at a distance of 0,1 m from an accessible surface. In this case,

instruction of use shall contain, in addition, provisions for limiting the exposure of people during operation (see

clause 5.3.3.
6 Measurement of Radiation Emissions

Measurement of radiation emission shall be done in order to confirm adequacy of design and compliance with the

requirements listed in 5. Measurement shall be made at accessible points around the machine. Specific techniques

for measuring radiation emissions are given in standards listed in A.3.
7 Instructions for Use

Manufacturers must provide sufficient information to enable the machine to be adjusted, operated, serviced and

maintained without risks to people from the radiation emissions. Where additional barriers to prevent close

approach are needed, criteria for deciding on their selection and location must be included in the instruction

manual.

Designers need to take into account the need for sealed sources to be tested for leakage according to

standardised methods (see A.1 ISO 9978) at regular intervals. If direct testing of the source is not possible,

designers should specify an alternative technique. Information for leakage testing has to be included in the

instruction for use.

If additional protective measures for limiting the exposure of people during operation are needed, according to

EURATOM Directive (see NOTE under 5.1), these protective measures shall be specify in the instructions for use.

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Annex A
(informative)
Examples of technical standards relating to ionizing radiation emissions
from machinery
A.1 Type C Standards relating to machines that may emit ionizing radiation
Number Date Title – Content
ISO 361 1975 Basic ionizing radiation symbol

Content: This standard specifies the symbol to be used to signify the potential presence of

ionizing radiation.
IEC 60777 1983 Terminology, quantities and units concerning ionizing radiation

Content: This standard defines terms, quantities and units used in radiation protection field.

ISO 921 1997 Nuclear energy – Vocabulary
Content: This standard defines terms used in nuclear energy domain.

ISO 2437 1972 Recommended practice for the X-ray inspection of fusion welded butt joints for aluminium

and its alloys and magnesium and its alloys 5 to 50 mm thick

Content: This standard provides general guidance on the techniques of weld radiography.

ISO 2855 1976 Radioactive materials – Packagings – Test for contents leakage and radiation leakage

Content: This standard specifies methods for contents leakage and radiation leakage tests

of prototypes of packages for the transport of radioactive materials. This standard may also

be of guidance to regulating authorities.

ISO 2919 1999 Radiation protection – Sealed radioactive sources – General requirements and

classification

Content: This standard establishes a system of classification of radioactive sources based

on testing performances and specifies general requirements, performances, production

tests, marking and certification. It provides a set of tests by which the manufacturer can

evaluate the safety of his product and by which the user can select types which are suitable

for the required application, especially where protection against release of radioactive

material is needed.
This standard may also be of guidance to regulating authorities.

ISO 12807 1996 Safe transport of radioactive materials – Leakage testing on packages

Content: This standard describes a method for relating permissible activity release rates of

the radioactivity content carried within a containment system equivalent gas leakage rates

under specified test conditions. It provides detailed guidance on the complex relationships

between an equivalent gas leakage test and a permissible activity release rate. This

standard may also be of guidance to regulating authorities.

ISO 9978 1992 Radiation protection – Sealed radioactive sources – Leakage test methods

Content: This standard specifies the different leakage test methods for sealed radioactive

source. It applies to control quality controls, production controls as well as to periodic

inspections for sealed radioactive sources. This standard may also be of guidance to

regulating authorities.
ISO/TR 4826 1979 Sealed radioactive sources – Leak test methods
Content: This technical report detailed the tests defined in ISO 2919.
ISO 3925 1978 Unsealed radioactive substances – Identification and certification

Content: This standard establishes the requirements for the identification and certification

of unsealed radioactive sources issued commercially by suppliers and which are intended

for further handling on treatment either physical or chemical. This standard may also be of

guidance to regulating authorities.
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Number Date Title – Content

ISO 3999-1 2000 Radiation Protection – Apparatus for industrial gamma radiography – Part 1: Specifications

for performances, design and tests

Content: This standard specifies the performance, design and test requirements for

gamma radiography with portable, mobile and fixed exposure containers of the various

categories of apparatus. It applies to apparatus designed to allow the controlled used of

gamma radiation emitted by a sealed radioactive source for industrial radiography purposes

in order that persons will be safeguarded when the apparatus is used in conformity with the

regulations in force regarding radiation protection.
This standard may also be of guidance to regulating authorities.

ANSI N 432 1980 Radiological safety for the design and construction of apparatus for gamma radiography

Content: This standard specifies the design and construction requirements for apparatus

designed to allow the controlled used of gamma radiation emitted by a sealed radioactive

source for industrial radiography.
This standard may also be of guidance to regulating authorities.
ISO 7205 1986 Radionuclide gauges – Gauges designed for permanent installation

Content: This standard establishes the main characteristics for radionuclide gauges

(classification of gauges and shielding devices – technical construction and performance

requirements – control and test methods – indication to be mention).
ANSI N 538 1979 Classification of industrial ionizing radiation gauging devices

Content: This standard establishes a system of classification of industrial radiation gauging

devices.

ANSI N 439 1991 Gamma radiography – Specifications for design and testing of apparatus

Content: This standard specifies the design and test requirements for apparatus designed

to allow the controlled used of gamma radiation emitted by a sealed radioactive source for

industrial radiography.
This standard may also be of guidance to regulating authorities.

ISO 5576 1997 Non-destructive testing – Industrial X-ray and gamma-ray radiology – Vocabulary

Content: This standard defines terms used in industrial radiographic testing.

ISO 5579 1998 Non-destructive testing – Radiographic examination of metallic materials by X- and

gamma-rays – Basic rules

Content: This standard specifies the basic rules for industrial X-and gamma radiography

for flaw detection purposes, using film techniques, applicable to metallic products and

materials.

ISO 5580 1985 Non-destructive testing – Industrial radiographic illuminators – Minimum requirements

Content: This standard specifies the minimum requirements for industrial non-destructive

testing apparatuses used for viewing radiographs.

ISO 8194 1987 Radiation protection – Clothing for protection against radioactive contamination – Design,

selection, testing and use

Content: This standard gives the characteristics of clothing protecting the wearer against

radioactive contamination brought about by contact with liquid or solids substances or by

atmospheric pollutants, such as solid particles, mist, gases or vapours. It includes guidance

and recommendations for choosing protective clothing (ventilated types as well as and non

ventilated types) and test methods for measuring the leak-t
...

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