ISO/IEC 7811-6:2008

Identification cards — Recording technique — Part 6: Magnetic stripe — High coercivity

ISO/IEC 7811 defines the characteristics of identification cards. ISO/IEC 7811-6:2008 provides criteria to which cards shall perform and specifies the requirements for such cards used for international interchange. It takes into consideration both human and machine aspects and states minimum requirements. ISO/IEC 7811-6:2008 specifies requirements for a high coercivity magnetic stripe (including any protective overlay) on an identification card, the encoding technique and coded character sets. It includes a modified algorithm for waveform measurement which produces more consistent results (incorporated from ISO/IEC 7811-6:2001/Amd.1:2005), and an additional requirement has been added for signal amplitude. ISO/IEC 7811-6:2008 specifies the following: the conditions for conformance; physical characteristics for the card (warpage and surface distortions) and the magnetic stripe area (location, height and surface profile, roughness, adhesion, wear, and resistance to chemicals); the signal amplitude performance characteristics of the magnetic stripe; the encoding specification including technique (F2F), angle of recording, bit density, flux transition spacing variation, and signal amplitude; the data structure including track format, the use of error correction techniques; the location of encoded tracks. ISO/IEC 7811-6:2008, together with a standard for test methods, provides for interchange between various types of identification card processing devices and systems.

Cartes d'identification — Technique d'enregistrement — Partie 6: Bandeau magnétique — Haute coercitivité

General Information

• Status: Withdrawn
• Publication Date: 21-May-2008
• Withdrawal Date: 21-May-2008
• ICS: 35.240.15 - Identification cards. Chip cards. Biometrics
• Technical Committee: ISO/IEC JTC 1/SC 17 - Cards and security devices for personal identification
• Drafting Committee: ISO/IEC JTC 1/SC 17/WG 1 - Physical characteristics and test methods for ID-cards
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 25-Aug-2014

Relations

• Revised: ISO/IEC 7811-6:2014 - Identification cards — Recording technique — Part 6: Magnetic stripe — High coercivity
• Effective Date: 10-May-2012
• Revises: ISO/IEC 7811-6:2001 - Identification cards — Recording technique — Part 6: Magnetic stripe — High coercivity
• Effective Date: 15-Apr-2008
• Revises: ISO/IEC 7811-6:2001/Amd 1:2005 - Identification cards — Recording technique — Part 6: Magnetic stripe — High coercivity — Amendment 1: Ui6 criteria and test method
• Effective Date: 15-Apr-2008

Standards Content (Sample)

INTERNATIONAL ISO/IEC
STANDARD 7811-6
Third edition
2008-06-01


Identification cards — Recording
technique —
Part 6:
Magnetic stripe — High coercivity
Cartes d'identification — Technique d'enregistrement —
Partie 6: Bandeau magnétique — Haute coercitivité




Reference number
ISO/IEC 7811-6:2008(E)
©
ISO/IEC 2008

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ISO/IEC 7811-6:2008(E)
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ISO/IEC 7811-6:2008(E)
Contents
Foreword. v
1 Scope .1
2 Conformance.1
3 Normative references .1
4 Terms and definitions .2
5 Physical characteristics of the identification card.4
5.1 Magnetic stripe area warpage .4
5.2 Surface distortions .4
6 Physical characteristics of the magnetic stripe .5
6.1 Height and surface profile of the magnetic stripe area .5
6.1.1 Surface profile of the magnetic stripe area.5
6.1.2 Height of the magnetic stripe area.7
6.2 Surface roughness .7
6.3 Adhesion of stripe to card .7
6.4 Wear of magnetic stripe from read/write head .7
6.5 Resistance to chemicals .7
7 Performance characteristics for the magnetic material .7
7.1 General.7
7.2 Testing and operating environment.8
7.3 Signal amplitude requirements for magnetic media.8
8 Encoding technique.10
9 Encoding specification, general.11
9.1 Angle of recording.11
9.2 Nominal bit density.11
9.3 Signal amplitude requirements for tracks 1, 2 and 3 .11
9.4 Bit configuration .12
9.5 Direction of recording .12
9.6 Leading and trailing zeroes .12
10 Encoding specifications .13
10.1 Alphanumeric track, track 1.13
10.1.1 Average bit density.13
10.1.2 Flux transition spacing variation .13
10.1.3 Coded character set .14
10.1.4 Maximum number of characters for ID-1 type card.16
10.2 Numeric track, Track 2 .16
10.2.1 Average bit density.16
10.2.2 Flux transition spacing variation .16
10.2.3 Coded character set .17
10.2.4 Maximum number of characters for ID-1 type card.17
10.3 Numeric track, Track 3 .17
10.3.1 Average bit density.17
10.3.2 Flux transition spacing variation .17
10.3.3 Coded character set .17
10.3.4 Maximum number of characters for ID-1 type card.18
11 Error detection .18
11.1 Parity .18
11.2 Longitudinal redundancy check (LRC).18
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ISO/IEC 7811-6:2008(E)
12 Location of encoded tracks . 18
Annex A (informative) Read compatibility of magnetic stripes (ISO/IEC 7811-2 and ISO/IEC 7811-6) . 20
Annex B (normative) Signal amplitude measurements. 21
Annex C (informative) Magnetic stripe abrasivity . 22
Annex D (informative) Static magnetic characteristics . 23


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ISO/IEC 7811-6:2008(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 7811-6 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 17, Cards and personal identification.
This third edition cancels and replaces the second edition (ISO/IEC 7811-6:2001). It also incorporates the
Amendment ISO/IEC 7811-6:2001/Amd.1:2005. The major changes from the second edition are as follows.
⎯ Wherever possible, the same definitions, criteria and test methods are used in ISO/IEC 7811-2 and
ISO/IEC 7811-6.
⎯ The algorithm defined in Figure 7 of ISO/IEC 7811-6:2001 has been changed to produce more consistent
results (incorporated from ISO/IEC 7811-6:2001/Amd.1:2005).
NOTE The requirements given in ISO/IEC 7811-4:1995 and ISO/IEC 7811-5:1995 were moved to Part 6 in the
second edition.
Notes in this part of ISO/IEC 7811 are only used for giving additional information intended to assist in the
understanding or use of the document. They do not contain provisions or requirements to which it is
necessary to conform in order to claim compliance with this part of ISO/IEC 7811.
ISO/IEC 7811 consists of the following parts, under the general title Identification cards — Recording
technique:
⎯ Part 1: Embossing
⎯ Part 2: Magnetic stripe — Low coercivity
⎯ Part 6: Magnetic stripe — High coercivity
⎯ Part 7: Magnetic stripe — High coercivity, high density
⎯ Part 8: Magnetic stripe — Coercivity of 51,7 kA/m (650 Oe)
⎯ Part 9: Tactile identifier mark
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INTERNATIONAL STANDARD ISO/IEC 7811-6:2008(E)

Identification cards — Recording technique —
Part 6:
Magnetic stripe — High coercivity
1 Scope
ISO/IEC 7811 defines the characteristics for identification cards as defined in Clause 4 of this part of
ISO/IEC 7811 and the use of such cards for international interchange.
This part of ISO/IEC 7811 specifies requirements for a high coercivity magnetic stripe (including any protective
overlay) on an identification card, the encoding technique and coded character sets. It takes into consideration
both human and machine aspects and states minimum requirements.
Coercivity influences many of the quantities specified in this part of ISO/IEC 7811 but is not itself specified.
The main characteristic of the high coercivity magnetic stripe is its improved resistance to erasure. This is
achieved with minimal probability of damage to other magnetic stripes by contact while retaining read
compatibility with magnetic stripes as defined in ISO/IEC 7811-2.
ISO/IEC 7811 provides criteria to which cards are to perform. No consideration is given within ISO/IEC 7811
to the amount of use, if any, experienced by the card prior to test. Failure to conform to specified criteria
should be negotiated between the involved parties.
ISO/IEC 10373-2 specifies the test procedures used to check cards against the parameters specified in this
part of ISO/IEC 7811.
NOTE  Numeric values in the SI and/or Imperial measurement system in this part of ISO/IEC 7811 may have been
rounded off and therefore are consistent with, but not exactly equal to, each other. Either system may be used, but the two
should not be intermixed or reconverted. The original design was made using the Imperial measurement system.
2 Conformance
A prerequisite for conformance with this part of ISO/IEC 7811 is conformance with ISO/IEC 7810. An
identification card is in conformance with this part of ISO/IEC 7811 if it meets all mandatory requirements
specified herein. Default values apply if no others are specified.
3 Normative references
The following referenced documents are indispensable for the application 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/IEC 4287, Geometrical Product Specifications (GPS) — Surface texture: Profile method — Terms,
definitions and surface texture parameters
ISO/IEC 7810, Identification cards — Physical characteristics
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ISO/IEC 7811-6:2008(E)
ISO/IEC 10373-1, Identification cards — Test methods — Part 1: General characteristics
ISO/IEC 10373-2, Identification cards — Test methods —Part 2: Cards with magnetic stripes
4 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 7810 and the following apply.
4.1
primary standard
set of reference cards established and maintained by the Physikalisch-Technische Bundesanstalt (PTB) that
represent the values of U and I designated RM7811-6
R R
4.2
secondary standard
reference card designated RM7811-6 that is related to the primary standard as stated in the calibration
certificate supplied with each card
NOTE  Secondary standards can be ordered from Q-Card, 301 Reagan Street, Sunbury, PA 17801, USA. The source
of secondary standards will be maintained at least until 2010.
4.3
unused un-encoded card
card possessing all the components required for its intended purpose, which has not been subjected to any
personalization or testing operation, and which has been stored in a clean environment with no more than
48 h exposure to daylight and at temperatures between 5 °C and 30 °C and humidity between 10 % and 90 %
without experiencing thermal shock
4.4
unused encoded card
card according to 4.3 that has only been encoded with all the data required for its intended purpose (e.g.
magnetic encoding, embossing, electronic encoding)
4.5
returned card
card according to 4.4 after it has been issued to the card holder and returned for the purpose of testing
4.6
flux transition
location of the greatest rate of change with distance of the magnetisation
4.7
reference current
I
R
minimum recorded current amplitude under the given test conditions that causes, on the reference card, a
readback signal amplitude equal to 80 % of the reference signal amplitude U at a density of 8 flux transitions
,
R
per millimetre (200 flux transitions per inch) as shown in Figure 6
4.8
reference flux level
F
R
flux level in the test head that corresponds to the reference current I

R
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ISO/IEC 7811-6:2008(E)
4.9
test recording currents
two recording currents defined by:
I = recording current corresponding to 2,8 F
min R
I = recording current corresponding to 3,5 F
max R
4.10
individual signal amplitude
U
i
base-to-peak amplitude of a single readback voltage signal
4.11
average signal amplitude
U
A
sum of the absolute value of the amplitude of each signal peak (U ) divided by the number of signal peaks (n)
i
for a given track over the length of the magnetic stripe area
4.12
reference signal amplitude
U
R
maximum value of the average signal amplitude of a reference card corrected to the primary standard
4.13
physical recording density
number of flux transitions per unit length recorded on a track
4.14
bit density
number of data bits stored per unit of length (bits/mm or bpi)
4.15
bit cell
distance between two clocking flux transitions
NOTE See Figure 11.
4.16
subinterval
distance that is nominally half of the distance between two clocking flux transitions
NOTE  See Figure 11.
4.17
demagnetisation current
I
d
D.C. current value that reduces the average signal amplitude to 80 % of the reference signal amplitude (U )
R
on a secondary reference card that has been encoded at a density of 20 ft/mm (500 ftpi) at a current of I
min
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ISO/IEC 7811-6:2008(E)
5 Physical characteristics of the identification card
The identification card shall conform to the specification given in ISO/IEC 7810.
WARNING — The attention of card issuers is drawn to the fact that information held on the magnetic
stripe may be rendered ineffective through contamination by contact with dirt and certain commonly
used chemicals including plasticizers. It should also be noted that any printing or screening placed
on top of the magnetic stripe must not impair the function of the magnetic stripe.
5.1 Magnetic stripe area warpage
Application of a 2,2 N (0.5 lbf) load evenly distributed on the front face opposite the magnetic stripe shall bring
the entire stripe within 0,08 mm (0.003 in) of the rigid plate.
5.2 Surface distortions
There shall be no surface distortions, irregularities or raised areas on both the front and the back of the card in
the area shown in Figure 1 that might interfere with the contact between the magnetic head and magnetic
stripe.

dimensions in millimetres (inches)
2,54 (0.100)
maximum
Top reference edge
Distortion-free
area
19,05 (0.750)
minimum

Figure 1 — Distortion-free area on card with magnetic stripe

If a raised signature panel area is located on the front or back of the card, then it shall be no closer to the top
edge of the card than 19,05 mm (0.750 in).
NOTE  Raised areas and distortions on other areas of the card may cause card transport problems with magnetic
stripe processing equipment resulting in reading or writing errors.
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ISO/IEC 7811-6:2008(E)
6 Physical characteristics of the magnetic stripe
6.1 Height and surface profile of the magnetic stripe area
The magnetic stripe area is located on the back of the card as shown in Figure 2.

dimensions in millimetres (inches)
5,54 (0.218)
max
Top reference edge
Minimum magnetic Magnetic stripe area a
stripe width (W)
2,92 (0.115) max
82,55 (3.250) min
For use of tracks 1 and 2: a = 11,89 (0.468) min
For use of tracks 1, 2, and 3: a = 15,95 (0.628) min

NOTE  In the case of the magnetic stripe area used for track 1 and 2, the dimension a as shown in Figure 2 of the
magnetic media could be less than the maximum dimension b as shown in Figure 12 for the location of track 2 data on the
card. It is desirable that the magnetic stripe area extend beyond the limits of the encoded track.
Figure 2 — Location of magnetic material for ID-1 type card


6.1.1 Surface profile of the magnetic stripe area
The maximum vertical deviation (a) of the transverse surface profile of the magnetic stripe area is shown
below. See Figure 3, Figure 4, and Figure 5. The slope of the surface profile curve shall be limited to: -4a/W <
slope < 4a/W.
When the bending stiffness value (see ISO/IEC 7810) for the card is 20 mm or more then the surface profile
limits are:
Minimum stripe width As shown in Figure 3A As shown in Figure 3B
W = 6,35 mm (0.25 in) a ≤ 9,5 µm (375 µin) a ≤ 5,8 µm (225 µin)
W = 10,28 mm (0.405 in)
a ≤ 15,4 µm (607 µin) a ≤ 9,3 µm (365 µin)

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ISO/IEC 7811-6:2008(E)
When the bending stiffness value (see ISO/IEC 7810) for the card is less than 20 mm then the surface profile
limits are:
Minimum stripe width As shown in Figure 3A As shown in Figure 3B
W = 6,35 mm (0.25 in)
a ≤ 7,3 µm (288 µin) a ≤ 4,5 µm (175 µin)
W = 10,28 mm (0.405 in)
a ≤ 11,7 µm (466 µin) a ≤ 7,3 µm (284 µin)

W
W
a
a
AB

Figure 3 — Surface profile


Abrupt drop
Permitted
Not permitted
Permitted Not permitted

Figure 4 — Surface profile examples

Irregular profiles as shown may result in poor quality encoding.

Figure 5 — Irregular surface profile examples

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ISO/IEC 7811-6:2008(E)
6.1.2 Height of the magnetic stripe area
The vertical deviation (h) of the magnetic stripe area relative to the adjacent surface of the card shall be:
-0,005 mm ( -200 µin) ≤ h ≤ 0,038 mm (1500 µin)
Spiking in the profile caused by the material "squirt out" in hot stamping is not part of the stripe. It shall not
extend above the magnetic stripe area height (h) as defined above.
6.2 Surface roughness
The average surface roughness (R ) of the magnetic stripe area shall not exceed 0,40 µm (15.9 µin) in both
a
the longitudinal and transverse directions when measured according to ISO/IEC 4287.
6.3 Adhesion of stripe to card
The stripe shall not separate from the card under normal use.
6.4 Wear of magnetic stripe from read/write head
Average signal amplitude (U ) and individual signal amplitude (U ) are measured before and after 2000 wear
A i
cycles and shall result in:
and
U ≥ 0,60 U U ≥ 0,80 U
A after A before i after A after

6.5 Resistance to chemicals
Average signal amplitude (U ) and individual signal amplitude (U ) are measured before and after short-term
A i
exposure as defined in ISO/IEC 10373-1 and shall result in:
U ≥ 0,90 U and U ≥ 0,90 U
A after A before i after A after

Average signal amplitude (U ) and individual signal amplitude (U) are measured before and after long-term
A i
exposure (24 hours) to acid and alkaline artificial perspiration, as defined in ISO/IEC 10373-1.
and
U ≥ 0,90 U U ≥ 0,90 U
A after A before i after A after

7 Performance characteristics for the magnetic material
7.1 General
The purpose of this section is to enable magnetic interchangeability between card and processing systems.
Media coercivity is not specified. The media's performance criteria, regardless of coercivity, is specified in 7.3.
This method uses a reference card whose material is traceable to the primary standard (see Clause 4). All
signal amplitude results from the use of the secondary reference card must be corrected by the factor supplied
with the secondary reference card. Test methods given in ISO/IEC 10373-2 shall be used.
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ISO/IEC 7811-6:2008(E)
7.2 Testing and operating environment
The testing environment for signal amplitude measurements is 23 °C ± 3 °C (73 °F ± 5 °F) and 40 % to 60 %
relative humidity. When tested under otherwise identical conditions, the average signal amplitude measured at
8 ft/mm (200 ftpi) shall not deviate from its value in the above test environment by more than 15 % after 5 min
exposure over the following operating environment range:
temperature -35 °C to 50 °C (-31 °F to 122 °F)
relative humidity 5 % to 95 %

7.3 Signal amplitude requirements for magnetic media
The requirements for recording characteristics of the card are shown in Table 1, and Figure 6 and Figure 7.
The media’s performance requirements specified in 7.3 shall be met in order to achieve improved resistance
to erasure, and to enable magnetic interchange between card and processing systems. The properties in
Annex D are intended as guidelines for magnetic material. Annex D is informative and shall not be used as
performance criteria for cards.
Table 1 — Signal amplitude requirements for unused unencoded cards
Description Density Test recording Signal Requirement
ft/mm (ftpi) current amplitude
result
Signal amplitude 8 (200)
I U 0,8 U ≤ U ≤ 1,2 U
min A1 R A1 R
Signal amplitude 8 (200)
I U U ≤ 1,26 U
min i1 i1 R
Signal amplitude 8 (200)
I U U ≥ 0,8 U
max A2 A2 R
Signal amplitude 20 (500)
I U U ≥ 0,65 U
max i2 i2 R
Resolution 20 (500)
I U U ≥ 0,7 U
max A3 A3 A2
Erasure 0
I , DC U U ≤ 0,03 U
min A4 A4 R
Extra pulse 0
I , DC U U ≤ 0,05 U
min i4 i4 R
Demagnetisation 0
I , DC U U ≥ 0,64 U
d A5 A5 R
Demagnetisation 0
I , DC U U ≥ 0,54 U
d i5 i5 R
Waveform 3 (75)
I U , U U ≤ 0,07 U
max i6 A6 i6 A6
U is the absolute value of the largest signal amplitude in the U measurement area as shown in Figure 7.
i6 i6
The slope of the saturation curve shall never be positive between I and I .
min max
NOTE  It is not permissible to combine the above requirements mathematically. These values are for unencoded card
tests and are not applicable for encoded cards.

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ISO/IEC 7811-6:2008(E)
U
A1
130
U
A2
Readback 120
voltage
100
U
R
(%U )
R
80
60 Example curve
40 Reference card curve
corrected to the
20
primary standard
Recording current
I I I
R min max

Figure 6 — Saturation curve example showing tolerance area at 8 ft/mm (200 ftpi)
NOTE  The curve defines the primary standard response (on a card). The window parameters define a card that will
be functional in the machine readable environment.


Midpoint Midpoint
between between
adjacent adjacent
peaks peaks
Last Last
Last Last
0 cross 0 cross
0 cross 0 cross
point point
point point
1,5a 1,5a
a a
U
i6
U
i6
measurement
measurement
area for U area for U
i6
i6

1. Find midpoint between 2 adjacent peaks.
2. Find 0 crossing point for waveform between midpoint and adjacent peak.
3. The measurement area is 1,5 times a (the distance between the midpoint and 0 cross point).
4. Find the largest signal amplitude level in the measurement area defined in the figure.
5.
The absolute value of this level is the U for the waveform.
i6

Figure 7 — Waveform measurements
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ISO/IEC 7811-6:2008(E)
8 Encoding technique
The encoding technique for each track is known as two-frequency recording. This method allows for serial
recording of self-clocking data. The encoding comprises data and clocking transitions together. A flux
transition occurring between clocks signifies that the bit is a "one" and the absence of a flux transition between
clocking transitions signifies that the bit is a "zero" (see Figure 8).

t t t t t t
000 0 0
111 1 1
101 0 0
t, indicates self-clocking (timing) intervals

Figure 8 — Examples of two-frequency encoding

The data shall be recorded as a synchronous sequence of characters without intervening gaps.
NOTE  Recording with a write current which is less than I may result in poor quality encoding.
min
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ISO/IEC 7811-6:2008(E)
9 Encoding specification, general
9.1 Angle of recording
The angle of recording shall be normal to the nearest edge of the card parallel to the magnetic stripe with a
tolerance of ± 20 min. The angle of recording (α) is determined by measuring the angle of the head gap when
the reading amplitude is maximum (see Figure 9).

Top reference edge
α =90° ± 20’
Back of card
Encoded track
Magnetic stripe
width

Figure 9 — Angle of recording

9.2 Nominal bit density
The nominal bit density for each of the tracks shall
...