prEN ISO 32543-3

SLOVENSKI STANDARD
01-september-2024
Neporušitvene preiskave - Značilnosti goriščne površine v industrijskih
rentgenskih sistemih za Neporušitveno preskušanje - 5. del: Meritve efektivne
velikosti goriščne površine za mini in mikro goriščne rentgenske aparate
Non-destructive testing - Characteristics of focal spots in industrial X-ray systems for use
in non-destructive testing - Part 5: Measurement of the effective focal spot size of mini
and micro focus X-ray tubes
Zerstörungsfreie Prüfung - Charakterisierung von Brennflecken in Industrie-
Röntgenanlagen für die zerstörungsfreie Prüfung - Teil 5: Messung der effektiven
Brennfleckgröße von Mini- und Mikrofokus-Röntgenröhren
Essais non destructifs - Caractéristiques des foyers émissifs des tubes radiogènes
industriels utilisés dans les essais non destructifs - Partie 5 : Mesurage de la taille des
foyers émissifs effectifs de tubes radiogènes à minifoyer ou à microfoyer
Ta slovenski standard je istoveten z: prEN 12543-5
ICS:
19.100 Neporušitveno preskušanje Non-destructive testing
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
prEN 12543-5
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2024
ICS 19.100 Will supersede EN 12543-5:1999
English Version
Non-destructive testing - Characteristics of focal spots in
industrial X-ray systems for use in non-destructive testing
- Part 5: Measurement of the effective focal spot size of
mini and micro focus X-ray tubes
Essais non destructifs - Caractéristiques des foyers Zerstörungsfreie Prüfung - Charakterisierung von
émissifs des tubes radiogènes industriels utilisés dans Brennflecken in Industrie-Röntgenanlagen für die
les essais non destructifs - Partie 5 : Mesure de la zerstörungsfreie Prüfung - Teil 5: Messung der
dimension du foyer émissif de tubes radiogènes à mini effektiven Brennfleckgröße von Mini- und Mikrofokus-
et micro foyer Röntgenröhren
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 138.
If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12543-5:2024 E
worldwide for CEN national Members.

prEN 12543-5:2024 (E)
Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Test method . 6
4.1 Principle and equipment . 6
4.2 Selections of distances and exposure time . 8
5 Measurement and determination of the focal spot size . 9
5.1 Measurement . 9
5.2 Determination . 11
6 Documentation . 11
Annex A (normative) Preferred values for the classification of X-ray µ-tube focal spot sizes. 13
Bibliography . 15

prEN 12543-5:2024 (E)
European foreword
This document (prEN 12543-5:2024) has been prepared by Technical Committee CEN/TC 138 “Non-
destructive testing”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12543-5:1999.
This document includes the following significant technical changes with respect to EN 12543-5:1999:
— Clause 2, normative references, updated;
— terms and definitions updated and supplemented;
— for test method, also the application of digital detector array devices and consequent requirements
are considered, see Clause 4.
EN 12543-5 is a part of series of standards; the other parts are the following:
— EN 12543-2, Non-destructive testing — Characteristics of focal spots in industrial X-ray systems for
use in non-destructive testing — Part 2: Pinhole camera radiographic method
— EN 12543-4, Non-destructive testing — Characteristics of focal spots in industrial X-ray systems for
use in non-destructive testing — Part 4: Edge method
— EN 12543-6, Non-destructive testing — Characteristics of focal spots in industrial X-ray systems for
use in non-destructive testing — Part 6: Measurement of the effective focal spot size of micro focus X-
ray tubes below 5 µm
The following parts have become invalid:
— EN 12543-1, Non-destructive testing — Characteristics of focal spots in industrial X-ray systems for
use in non-destructive testing — Part 1: Scanning method
— EN 12543-3, Non-destructive testing — Characteristics of focal spots in industrial X-ray systems for
use in non-destructive testing — Part 3: Slit camera radiographic method
prEN 12543-5:2024 (E)
Introduction
In order to cover the large range of effective focal spot sizes, four different methods are described in
EN 12543-2, EN 12543-4, EN 12543-5 and EN 12543-6.
The pinhole method of EN 12543-2 is intended for effective focal spot sizes above 100 µm.
The penetrameter method of EN 12543-4 is intended for field applications when users must observe
the effective focal spot on a regular basis and the pinhole method is non-practical.
The edge measurement method of EN 12543-5 is intended for measurement of effective focal spot sizes
between 5µm and 300 µm and mainly for the use with µ-Focus tubes.
The line pair measurement method of EN 12543-6 is intended for effective focal spot sizes smaller than
5 µm.
The reconstruction method of EN 12543-7 is intended for effective spot sizes < 100 µm as alternative to
the pin hole method of EN 12543-2.
In the overlapping ranges the different methods give similar values which allow using the dedicated
method also a little bit outside the above specified ranges.
prEN 12543-5:2024 (E)
1 Scope
This document specifies a method for the measurement of focal spot dimensions within the range of
5 µm to 300 µm of X-ray systems up to and including 225 kV tube voltage. This determination is based
on the evaluation of an image with a dedicated focal spot that has been radiographically recorded using
an edge and evaluated with a digital method.
The imaging quality and the resolution of X-ray images depend highly on the characteristics of the
effective focal spot, in particular the size and the two-dimensional intensity distribution as seen from
the detector plane.
For the characterization of commercial X-ray tube types (i.e. for advertising or trade) the specific
maximum values of Annex A are preferred.
NOTE The same procedure can be used at higher kilovoltages by agreement but the accuracy of the
measurement can be poorer.
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.
EN ISO 11699-1, Non-destructive testing — Industrial radiographic film — Part 1: Classification of film
systems for industrial radiography (ISO 11699-1)
EN ISO 19232-5, Non-destructive testing — Image quality of radiographs — Part 5: Determination of the
image unsharpness and basic spatial resolution value using duplex wire-type image quality indicators
(ISO 19232-5)
ISO 16371-1, Non-destructive testing — Industrial computed radiography with storage phosphor imaging
plates — Part 1: Classification of systems
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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/
3.1
thermal focal spot
X-ray producing area of the target as viewed from a position perpendicular to the target surface
Note 1 to entry: Also named as actual focal spot in [1].
3.2
effective focal spot
X-ray producing area of the target as viewed by a detection device from the detector plane
Note 1 to entry: Also named optical focal spot in other publications.
prEN 12543-5:2024 (E)
3.3
effective size of focal spot
s
measured focal spot size
Note 1 to entry: For measurement and determination, see Clause 5.
3.4
nominal focal spot size
SS
rounded focal spot size
Note 1 to entry: The nominal focal spot size is determined from Table A.1 based on the measured focal spot, s .
LSF
3.5
focal spot class
FS
classification value for X-ray tubes, which have a focal spot size in a defied range
Note 1 to entry: The ranges of focal spot sizes are defined in Annex A, Table A.1
3.6
signal to noise ratio
SNR
ratio of mean grey value to the standard deviation of the grey values (noise) measured in a region of
interest
Note 1 to entry: Grey values are numeric values of pixels, which are directly proportional to the detector
exposure dose and having a value of zero, if the detector was not exposed.
3.7
contrast-to-noise ratio
CNR
ratio of the difference of the mean signal levels between two image areas to the averaged standard
deviation of the signal levels
3.8
anticipated focal spot size
afs
focal spot size of an X-ray tube as stated in the X-ray tube specification or estimated from the X-ray tube
development documents
4 Test method
4.1 Principle and equipment
This method is based on indirect measurement of the focal spot size by measuring the geometric
unsharpness. For this purpose, sharp edges are imaged either on a film, an Imaging Plate (CR), or by
means of a radioscopic or digital detector array (DDA) using a relatively high geometric magnification.
The digital image is dimensionally evaluated.
The following equipment is required for the measurement if using a film:
— a test object as described below;
prEN 12543-5:2024 (E)
— films, without screens, of sufficient size to image magnified test object and region around test object
to obtain a profile as shown in Figure 1. The film system shall meet the requirements of film system
class C2 according to EN ISO 11699-1 and shall be packed in low absorption polyethylene cassettes
using no front screens;
— film cassettes made of low absorbing material (e.g. polyehtylene);
— a film holder;
— a film processing unit;
— a film scanner capable of reading densities of D > 4,0 configured such that the pixel size is
appropriate for the measurement (refer to Clause 5). The image shall be of sufficient size to image
the magnified test object and region around test object to obtain a profile as shown in Figure 1.
The following equipment is required for the measurement if using computed radiography (CR):
— a test object as described below;
— a computed radiography system, consisting of an imaging plate and scanner, configured such that
the pixel size is appropriate for the measurement (refer to Clause 5). The image shall be of sufficient
size to image magnified test object and region around test object to obtain a profile as shown in
Figure 1.
The computed radiography system shall meet the requirements of ISO 16371, class I, II or Special and
image plates shall be packed in low absorption cassettes
...