ISO 4090:2001

INTERNATIONAL ISO
STANDARD 4090
Third edition
2001-08-15
Photography — Medical radiographic
cassettes/screens/films and hard-copy
imaging films — Dimensions and
specifications
Photographie — Cassettes/écrans/films radiographiques médicaux et films
d'imagerie copie-papier — Dimensions et spécifications
Reference number
ISO 4090:2001(E)
©
ISO 2001

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ISO 4090:2001(E)
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ii © ISO 2001 – All rights reserved

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ISO 4090:2001(E)
Contents Page
Foreword.v
Introduction.vi
1 Scope .1
2 Normative references .1
3 Terms and definitions .1
4 Conditions for measurement of dimensions .2
5 Radiographic cassettes .2
6 Mammography cassettes.8
7 Screens .13
8 Films.14
9 Package marking .16
Annex A (informative) Traditional sizes of medical films in rolls.18
Annex B (normative) Squareness.20
Annex C (informative) Test for light-tightness .21
Annex D (informative) Test for screen-film contact (Radiographic cassettes).22
Annex E (normative) Test for screen-film contact (Mammography cassettes) .24
Annex F (informative) Metric conversion of inch nominal sizes .27
Annex G (informative) Dimensional stability of film.28
Annex H (informative) Quantity packaging.29
Annex I (informative) Sizes of inch origin — Film dimension exceptions.30
Figures
Figure 1 — Cassette outside dimensions .6
Figure 2 — Mammography cassette dimensions for field radiation detector .12
Figure 3 — Corner rounding limits of film.14
Tables
Table 1 — Preferred radiographic cassette sizes of metric origin .3
Table 2 — Preferred radiographic cassette sizes of inch origin.4
Table 3 — Recognized radiographic cassette sizes of metric origin.4
Table 4 — Recognized radiographic cassette sizes of inch origin .5
Table 5 — Preferred mammography cassette sizes.9
Table 6 — Recognized mammography cassette sizes .9
Table 7 — Cutting and tolerance rules for screen sizes of metric origin and new sizes.13
Table 8 — Preferred hard-copy film sizes of metric origin.15
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ISO 4090:2001(E)
Table 9 — Preferred hard-copy film sizes of inch origin .15
Table 10 — Recognized hard-copy film size of metric origin.15
Table 11 — Recognized hard-copy film sizes of inch origin .15
Table 12 — Cutting and tolerance rules for film sizes of metric origin and new sizes .16
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ISO 4090:2001(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 4090 was prepared by Technical Committee ISO/TC 42, Photography.
This third edition cancels and replaces the second edition (ISO 4090:1991) which has been technically revised.
Annexes B and E form a normative part of this International Standard. Annexes A, C, D and F to I are for
information only.
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ISO 4090:2001(E)
Introduction
This International Standard is based on a combination and revision of the following five documents:
� ANSI/NAPM ITI. 49-1995, Photography (Films) — Medical radiographic cassettes/screens/films — Dimensions
and specifications
� IEC 60406:1997, Cassettes for medical X-ray diagnosis — Radiographic cassettes and mammographic
cassettes
� IEC 60658:1979, Radiographic intensifying screens for medical use — Dimensions
� ISO WD1/4090, Photography — Film Dimensions — Medical radiography
� ISO WD2/15264, Photography — Medical hard copy imaging film — Dimensions and specifications
The aim of this International Standard is to bring together all standardized information about dimensions and
related specifications of photographic materials in the form of sheets and related products (screens and cassettes);
all of which are intended for use in medical radiography. The worldwide community using radiographic equipment
will benefit by having all this information in a single text.
This text of this International Standard is not intended to change the contents of the aforementioned documents,
but only to bring them together and to resolve the discordance existing between the different standards or standard
projects. The existence of a single International Standard for sheet films and related products will resolve existing
differences by converting inch sizes to metric sizes.
Inch nominal sizes and inch dimensions are not found in this International Standard. Informative annex F describes
the transition from inch to metric dimensions for the reader. Conversion to metric specifications has resulted in a
potentially confusing situation. Use of the same nominal dimension (20� 40 and 20� 25, for example) might imply
to the reader that the aims and tolerances should be identical. In some cases, where one size is of inch origin and
the other is of metric origin, this is not true. Therefore, TC 42 agreed that it would be best to separate tables into
sizes of metric origin versus sizes of inch origin.
By combining the existing documents and the dimensional tables, the reader can now easily compare sizes of
films, screens and cassettes — all in a glance. Combination has also facilitated a significant comparison of
preferred and recognized sizes, as well as a reconciliation of whether films and screens properly fit inside their
corresponding cassettes. This comparison has resulted in a significant improvement in the agreement between
sizes, as well as component “fit”.
This International Standard refers to mammography cassettes as either preferred sizes or recognized sizes. All
new mammography cassettes must conform to the dimensions given as “preferred”. The dimensions given for
recognized sizes are listed in order to inform the reader regarding an older style of mammography cassettes.
Although the older style cassettes are no longer preferred (no longer the industry standard), use of this style
throughout the world is expected to continue for some time. So, they are listed here as “recognized” only.
Medical radiographic films in roll form are not a part of this International Standard. Use of roll films appears well
established and stable, but does not justify a new, stand-alone standard. In order to assist the reader, information
regarding roll films is listed in informative annex A.
Annexes G, H and I provide information on the dimensional stability of film, quantity packaging and sizes of inch
origin (film dimension exceptions), respectively.
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INTERNATIONAL STANDARD ISO 4090:2001(E)
Photography — Medical radiographic cassettes/screens/films and
hard-copy imaging films — Dimensions and specifications
1 Scope
This International Standard specifies the nominal sizes, aim dimensions with tolerances, weights, and certain tests
for medical radiographic cassettes, screens, and films. It includes medical hard-copy imaging films in the form of
sheets, such as laser films and video.
This International Standard also includes information regarding the appropriate marking of these products, and
special attention is given to cassettes/screens/films used for mammography.
This International Standard does not include films in roll format (see informative annex A).
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this International Standard. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this International Standard are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
ISO 554:1976, Standard atmospheres for conditioning and/or testing — Specifications.
IEC 61267:1994, Medical diagnostic X-ray equipment — Radiation conditions for use in the determination of
characteristics.
3 Terms and definitions
For the purposes of this International Standard, the following terms and definitions apply.
3.1
preferred mammography sizes
current industry standard, reflecting modern industry trends
NOTE Aim and tolerance dimensions are different for preferred sizes versus recognized sizes.
3.2
recognized mammography sizes
former industry standard, listed because this older format is expected to be used in clinical applications worldwide
for sometimetocome
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ISO 4090:2001(E)
4 Conditions for measurement of dimensions
The dimensions and tolerances specified in this International Standard shall apply at the time of manufacture
(except where specifically stated otherwise), when measured under atmospheric conditions of (23� 2) °C and
(50� 5) % relative humidity, as specified in ISO 554.
All measuring instrument calibrations should be conducted at a temperature of 20 °C, as specified in ISO 1:1975,
Standard reference temperature for industrial length measurements, and a relative humidity of 50 %.
5 Radiographic cassettes
5.1 Dimensions
5.1.1 Nominal sizes, aim and tolerance dimensions
Nominal sizes, aim and tolerance dimensions and weight for preferred radiographic cassette sizes shall conform to
the values given in Tables 1 and 2.
Nominal sizes, aim and tolerance dimensions and weight for recognized radiographic cassette sizes shall conform
to the values given in Tables 3 and 4.
The materials and design of the cassette shall ensure that, under normal conditions of use, the shape and
dimensions comply with the limits for the outer dimensions (OD) and inner dimensions (ID) given in Tables 1, 2, 3
and 4, over a relative humidity range from 30 % to 85 % and a temperature range from 10 °Cto40 °C.
5.1.2 Denomination
Radiographic cassettes are denoted by the nominal size expressed in numerical values (in centimetres) without
adding the measurement unit “cm”.
EXAMPLE Cassette 18 � 24 (eighteen by twenty-four) denotes a radiographic cassette for a film with nominal size
18 cm � 24 cm.
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ISO 4090:2001(E)
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Table 1 — Preferred radiographic cassette sizes of metric origin
Nominal Film size Screen size Cassette ID Cassette OD Thickness Weight
size without
screen
cm mm mm mm mm mm g
Min. Aim Max. Min. Aim Max. Min. Aim Max. Min. Aim Max. Aim and Max.
tolerance
�1
13 � 18 127 � 177 128 � 178 129 � 179 127 � 177 130 � 180 131 � 181 131,5 � 132 � 182 133 � 183 156,5 � 157,5 � 158,5 � 500
15
�2
181,5 206,5 208,5 208,5
�1 800
18 � 24 177 � 237 178 � 238 179 � 239 177 � 237 180 � 240 181 � 241 181,5 � 182 � 242 183 � 243 206,5 � 207,5 � 208,5 �
15
�2
241,5 266,5 267,5 268,5
18 � 43 177 � 429 178 � 430 179 � 431 177 � 429 180 � 432 181 � 433 181,5 � 182 � 434 183 � 435 206,75 � 207,75 � 208,75 � �1 1 000
15
�2
433,5 458,5 459,5 460,5
�1
20 � 40 197 � 397 198 � 398 199 � 399 197 � 397 200 � 400 201 � 401 201,5 � 202 � 402 203 � 403 226,5 � 227,5 � 228,5 � 1 000
15
�2
401,5 426,5 427,5 428,5
�1 1 200
24 � 30 237 � 297 238 � 298 239 � 299 237 � 297 240 � 300 241 � 301 241,5 � 242 � 302 243 � 303 266,5 � 267,5 � 268,5 �
15
�2
301,5 326,5 327,5 328,5
30 � 40 297 � 397 298 � 398 299 � 399 297 � 397 300 � 400 301 � 401 301,5 � 302 � 402 303 � 403 326,5 � 327,5 � 328,5 � �1 1 900
15
�2
401,5 426,4 427,5 428,5
�1
30 � 90 297 � 896 298 � 897,5 299 � 899 297 � 897 300 � 900 301 � 901 301,5 � 302 � 902 303 � 903 326,5 � 327,5 � 328,5 � —
16,5
�3,5
(see note) 901,5 926,5 927,5 928,5
�1 —
30 � 120 297 � 298 � 299 � 297 � 300 � 301 � 301,5 � 302 � 1 202 303 � 326,5 � 327,5 � 328,5 �
16,5
�3,5
(see note) 1 196 1 197,5 1 197 1 197 1 200 1 201 1 201,5 1 203 1 226,5 1 227,5 1 228,5
Dental radiography (Extra-oral)
13 � 30 127 � 297 128 � 298 129 � 299 127 � 297 130 � 300 131 � 301 131,5 � 132 � 302 133 � 303 156,6 � 157,6 � 158,6 � �1 800
15
�2
301,5 326,5 327, 5 328,5
�1 800
15 � 30 147 � 297 148 � 298 149 � 299 147 � 297 150 � 300 151 � 301 151,5 � 152 � 302 153 � 303 176,5 � 177,5 � 178,5 �
15
�2
301,5 326,5 327,5 328,5
NOTE These sizes may be formed from three smaller sheets attached together. The resultant sheet may be folded to facilitate shipping.

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ISO 4090:2001(E)
4 © ISO 2001 – All rights reserved
Table 2 — Preferred radiographic cassette sizes of inch origin
Nominal Film size Screen size Cassette ID Cassette OD Thickness Weight
size without
screen
cm mm mm mm mm mm g
Min. Aim Max. Min. Aim Max. Min. Aim Max. Min. Aim Max. Aim and Max.
tolerance
�1
20 � 25 200,8 � 201,6 � 202,4 � 200,8 � 201,6 � 202,4 � 204,7 � 205,2 � 206,2 � 229,7 � 230,7 � 231,7 � 1 000
15
�2
252 252,8 253,6 252 252,8 253,6 255,5 256 257 280,5 281,5 282,5
�1 1 900
35 � 35 353 � 353 354 � 354 355 � 355 353 � 353 356 � 356 357 � 357 357,5 � 358 � 358 359 � 359 382,5 � 383,5 � 384,5 �
15
�2
357,5 382,5 383,5 384,5
35 � 43 353 � 429 354 � 430 355 � 431 353 � 429 356 � 432 357 � 433 357,5 � 358 � 434 359 � 435 382,5 � 383,5 � 384,5 � �1 2 100
15
�2
433,5 458,5 459,5 460,5
Table 3 — Recognized radiographic cassette sizes of metric origin
Nominal Film size Screen size Cassette ID Cassette OD Thickness Weight
size without
screen
cm mm mm mm mm mm g
Min. Aim Max. Min. Aim Max. Min. Aim Max. Min. Aim Max. Aim and Max.
tolerance
24 � 24 237 � 237 238 � 238 239 � 239 237 � 237 240 � 240 241 � 241 241,5 � 242 � 242 243 � 243 266,5 � 267,5 � 268,5 � �1 1 000
15
�2
241,5 266,5 267,5 268,5
30 � 30 297 � 297 298 � 298 299 � 299 297 � 297 300 � 300 301 � 301 301,5 � 302 � 302 303 � 303 326,5 � 327,5 � 328,5 � �1 1 400
15
�2
301,5 326,5 327,5 328,5
�1
40 � 40 397 � 397 398 � 398 399 � 399 397 � 397 400 � 400 401 � 401 401,5 � 402 � 402 403 � 403 426,5 � 427,5 � 428,5 � 1 900
15
�2
401,5 426,5 427,5 428,5
�1 —
20 � 96 197 � 956 198 � 199 � 959 197 � 956 200 � 960 201 � 961 201,5 � 202 � 962 203 � 963 226,5 � 227,5 � 228,5 �
16,6
�3,5
(see note) 957,5 961,5 986,5 987,5 988,5
NOTE This size may be formed from three smaller sheets attached together. The resultant sheet may be folded to facilitate shipping.

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ISO 4090:2001(E)
© ISO 2001 – All rights reserved 5
Table 4 — Recognized radiographic cassette sizes of inch origin
Nominal Film size Screen size Cassette ID Cassette OD Thickness Weight
size without
screen
cm mm mm mm mm mm g
Min. Aim Max. Min. Aim Max. Min. Aim Max. Min. Aim Max. Aim and Max.
tolerance
�1
25 � 30 252 � 252,8 � 253,6 � 252 � 252,8 � 253,6 � 255,5 � 256 � 257 � 280,5 � 281,5 � 282,5 � 1 200
15
�2
302,4 303,2 304,0 303,2 304 304,8 306,3 306,8 307,8 331,3 332,3 333,3
�1 1 900
28 � 35 277,8 � 278,6 � 279,4 � 277,8 � 278,6 � 279,4 � 280,9 � 281,4 � 282,4 � 305,9 � 306,9 � 307,9 �
15
�2
354 354,8 355,6 354 354,8 355,6 357,1 357,6 358,6 382,1 383,1 384,1
30 � 35 297,2 � 298 � 354 298,8 � 297 � 353 300 � 356 301 � 357 301,5 � 302 � 358 303 � 359 326,5 � 327,5 � 328,5 � �1 1 900
15
�2
353,2 354,8 357,5 382,5 383,5 384,5
�1
30 � 38 302,4 � 303,2 � 304 � 303,2 � 304 � 304,8 � 306,3 � 306,8 � 307,8 � 331,3 � 332,3 � 333,3 � 1 900
15
�2
378,6 379,4 380,2 379,4 380,2 381 382,5 383 384 407,5 408,5 409,5

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ISO 4090:2001(E)
5.1.3 Outer dimensions (OD)
The outer dimensions, in the plane of the film, shall be 27,5 mm � 1 mm more than the nominal size of the
cassette.
Cassettes of nominal sizes that have both dimensions not exceeding 43,2 cm shall have an aim thickness of
15 mm, minimum thickness of 13 mm, and maximum thickness of 16 mm.
Cassettes of nominal sizes that have one or both dimensions greater than 43,2 cm shall have an aim thickness of
16,5 mm, minimum thickness of 13 mm, and maximum thickness of 17,5 mm.
The specified thickness of a cassette is intended to ensure that the cassette can be properly fixed in a defined
position under a load (e.g. within a holder or rails). In no case shall the maximum thickness tolerance, as given in
Tables 1, 2, 3 and 4, be exceeded in any part of the cassette.
The corners and edges of the cassette, as shown in the top view of Figure 1, shall be smoothed or shaped over a
quarter circle to a radius (r ) of 10 mm maximum and 1 mm minimum.
1
The other edges, as shown in the side view of Figure 1, shall be smoothed over a quarter circle to a radius (r )of at
2
least 1,5 mm.
The greatest value for the radius results from the minimum required planes as given by the dimensions A and B in
the side view of Figure 1.
All parts of the cassette, such as hinges, locks and marking devices, shall be within the tolerances given in
Tables 1, 2, 3 and 4 and shall be within the limits for corners and edges.
Dimensions in millimetres
Key
1 Thickness (see Tables 1, 2, 3, 4)
Dimension Radiographic cassettes Mammography cassettes
r
Min. = 1; Max. = 10 Min = 3; Max = 10
1
r 1,5 minimum 1,5 minimum
2
A greater than 11 greater than 11
B greater than 11 greater than 11
Figure 1 — Cassette outside dimensions
5.1.4 Inner dimensions (ID)
The inner dimensions, in the plane of the film, shall be as given in Tables 1, 2, 3 and 4.
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ISO 4090:2001(E)
5.2 Geometric accuracy
5.2.1 Outer geometric accuracy
5.2.1.1 Squareness
The squareness of the cassette shall conform to the requirements given in normative annex B.
5.2.1.2 Flatness
When a closed radiographic cassette is laid on a flat surface, no part of the cassette shall depart from that surface
by more than 16 mm.
5.2.1.3 Parallelism
The front and back of the radiographic cassette shall be parallel to each other within 0,3 mm over any length of
100 mm.
5.2.2 Inner geometric accuracy
5.2.2.1 Squareness
The squareness of the cassette shall conform to the requirements given in normative annex B.
5.3 Incident beam attenuation
The front cover of the cassette shall have an absorption not greater than the equivalent of 1,8 mm of pure
aluminum (99 %) when traversed by radiation of quality RQA 4 [approximately 60 kV (see IEC 61267)].
5.4 Cassette design
5.4.1 Opening
When the cassette is lying on a plane surface, it shall be possible to open the back in such a way that it contacts
the surface without the hinges being stressed.
5.4.2 Marking device
In order to identify the film in use, the cassette shall either permit the use of a means for marking the film, or it shall
be equipped on its outside with a means for labelling.
The provision of a means to allow a semi-transparent marking of the cassette's own characteristics (e.g.
intensifying screens, types of films, etc.) is optional.
5.4.3 Light-tightness
Under normal conditions of use, the cassette shall be light-tight. Informative annex C describes a typical test for
light-tightness.
5.4.4 Screen-film contact
The cassette shall ensure close screen-film contact over the entire area between the intensifying screens and the
radiographic film. Informative annex D describes a test method for screen-film contact of radiographic cassettes.
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ISO 4090:2001(E)
5.4.5 Front cover recognition
Unless cassettes are specifically designed so that either side can be used as the front cover, they shall be
designed so that the front cover is distinguishable from the back by touch when handling the cassette with
protective gloves.
The distinction between the front and back covers shall be clearly visible under normal safelight conditions.
5.4.6 Handling
Radiographic cassettes of the same nominal size shall be able to be placed in, removed from, and stacked in a
container, and also handled by devices without affecting each other and without opening.
6 Mammography cassettes
6.1 Classification
This International Standard refers to mammography cassettes as either preferred or recognized. All new
mammography cassettes shall conform to the dimensions given as “preferred”.
The dimensions given for recognized sizes are listed in order to inform the reader regarding an older style of
mammography cassettes. Although the older style cassettes are no longer preferred (no longer the industry
standard), use of this style throughout the world is expected to continue for some time. Therefore, they are listed
here as “recognized” only.
6.2 Dimensions
6.2.1 Nominal sizes, aim and tolerance dimensions
Nominal sizes, aim and tolerance dimensions, and weight for preferred mammography cassette sizes shall conform
to the values given in Table 5.
Nominal sizes, aim and tolerance dimensions, and weight for recognized mammography cassettes shall conform to
the values given in Table 6.
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ISO 4090:2001(E)
© ISO 2001 – All rights reserved 9
Table 5 — Preferred mammography cassette sizes
Nominal Film size Screen size Cassette ID Cassette OD Thickness Weight
size without
screen
cm mm mm mm mm mm g
Min. Aim Max. Min. Aim Max. Min. Aim Max. Min. Aim Max. Aim and Max.
tolerance
�1 690
18 � 24 177 � 237 178 � 238 179 � 239 177 � 237 178 � 238 179,5 � 179 � 181 � 242 182 � 243 193 � 194,5 � 196 �
15
�2
239 241,5 266,5 267,5 268,5
24 � 30 237 � 297 238 � 298 239 � 299 237 � 297 238 � 299 239,5 � 239 � 241 � 302 242 � 303 253 � 254,5 � 256,5 � �1 850
15
�2
301,4 301,5 326,5 327,5 328,5
Table 6 — Recognized mammography cassette sizes
Nominal Film size Screen size Cassette ID Cassette OD Thickness Weight
size without
screen
cm mm mm mm mm mm g
Min. Aim Max. Min. Aim Max. Min. Aim Max. Min. Aim Max. Aim and Max.
tolerance
18 � 24 177 � 237 178 � 238 179 � 239 174 � 237 175 � 238 176 � 239 > 179 � > 179 � 183 � 241 193 � 194,5 � 196 � �0 500
20,5
�2
239,5 240 242,5 243,5 244,5
�0 625
24 � 30 237 � 297 238 � 298 239 � 298,45 234 � 297 235 � 298 236 � 298,45 > 239 � 298,5 > 239 � 299 243 � 300 253,5 � 304 255 � 305 256,5 � 306
20,5
�2

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ISO 4090:2001(E)
6.2.2 Denomination
Mammography cassettes are denoted by the nominal size expressed in numerical values (in centimetres) without
adding the measurement unit “cm”. Inclusion of the letter M, for clarification as mammography, is recognized.
EXAMPLE Cassette 18 � 24 (eighteen by twenty-four), or cassette M 18 � 24, denotes a mammography cassette for a film
with nominal size 18 cm � 24 cm.
6.2.3 Outer dimensions (OD)
The outer dimensions of mammography cassettes shall be as given in Tables 5 and 6.
The specified thickness of a cassette is intended to ensure that the cassette can be properly fixed in a defined
position (e.g. within a holder or rails). In no case shall the maximum thickness tolerance, as given in Tables 5 and
6, be exceeded in any part of the cassette.
The corners and edges of the cassette, as shown in the top view of Figure 1, shall be smoothed or shaped over a
quarter circle to a radius (r ) of 10 mm maximum and 3 mm minimum.
1
The other edges, as shown in the side view of Figure 1, shall be smoothed over a quarter circle to a radius (r )of at
2
least 1,5 mm.
The greatest value for the radius results from the minimum required planes, as given by dimensions A and B in the
side view of Figure 1.
6.2.4 Inner dimensions (ID)
The inner dimensions, in the plane of the film, shall conform to the values given in Tables 5 and 6.
6.3 Geometric accuracy
6.3.1 Outer geometric accuracy
6.3.1.1 Squareness
The squareness of the cassette shall conform to the requirements given in normative annex B.
6.3.1.2 Flatness
When a closed mammography cassette is laid on a flat surface, no part of the cassette shall depart from that
surface by more than 16 mm, except for the nominal size 18� 24 where no part shall depart from that surface by
more than 21 mm.
6.3.1.3 Parallelism
The front and back of the m
...