Gas cylinders — Identification and marking using radio frequency identification technology — Part 2: Numbering schemes for radio frequency identification

ISO 21007-2:2005 establishes a common framework for data structure to enable the unambiguous identification in gas cylinder applications and for other common data elements in this sector. ISO 21007-2:2005 enables a structure to allow some harmonization between different systems. However, it does not prescribe any one system and has been written in a non-mandatory style so as not to make it obsolete as technology changes. The main body of ISO 21007-2:2005 excludes any data elements that form any part of transmission or storage protocols such as headers and checksums.

Bouteilles à gaz — Identification et marquage à l'aide de la technologie d'identification par radiofréquences — Partie 2: Schémas de numérotage pour identification par radiofréquences

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Publication Date
07-Aug-2005
Withdrawal Date
07-Aug-2005
Current Stage
9599 - Withdrawal of International Standard
Completion Date
28-Jan-2013
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INTERNATIONAL ISO
STANDARD 21007-2
First edition
2005-07-15


Gas cylinders — Identification and
marking using radio frequency
identification technology —
Part 2:
Numbering schemes for radio frequency
identification
Bouteilles à gaz — Identification et marquage à l'aide de la technologie
d'identification par radiofréquences —
Partie 2: Schémas de numérotage pour identification par
radiofréquences





Reference number
ISO 21007-2:2005(E)
©
ISO 2005

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ISO 21007-2:2005(E)
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ii © ISO 2005 – All rights reserved

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ISO 21007-2:2005(E)
Contents Page
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and numerical notations .2
4 Data presentation. 3
5 Gas cylinder identification structure . 4
6 Gas cylinder identification data schemes. 5
7 Air interface specifications. 16
8 Transponder memory addressing. 17
Annex A (informative) Technical solution. 18
Annex B (informative) List of codes for registration bodies. 19
Annex C (informative) List of codes for gas cylinder manufacturers. 20
Annex D (informative) Gas quantity units code . 40
Annex E (informative) Host to interrogator to MODBUS communication protocol. 41

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ISO 21007-2:2005(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 2.
The main task of technical committees is to prepare International Standards. 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 document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 21007-2 was prepared by Technical Committee ISO/TC 58, Gas cylinders, Subcommittee SC 4,
Operational requirements for gas cylinders.
ISO 21007 consists of the following parts, under the general title Gas cylinders — Identification and marking
using radio frequency identification technology:
— Part 1: Reference architecture and terminology
— Part 2: Numbering schemes for radio frequency identification

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ISO 21007-2:2005(E)
Introduction
Throughout industry and in commerce, trade and the domestic sector, the employment of gas cylinders
(referred to as GC in this part of ISO 21007) to enable the local consumption and use of gases and liquids,
without the need for in-situ high cost permanent pressure vessel installations, is an important part of modern
practice.
Such cylinders may provide complex gas mixes for medical, industrial or research use.
As the cylinders may contain a wide variety of gases, identification is of paramount importance. It is
mandatory to be able to uniquely identify each cylinder. As many contents are of limited life, and for product
quality and liability tracking and tracing, in some circumstances it may be necessary or desirable to identify not
only the type of gas or liquid, but also such details as filling station, batch and date of fill.
Various methods and technologies such as physical identification through indentation; paper, card, metal, and
plastic labeling; colour code identification; bar coding and, in some circumstances, vision systems are already
used to make or assist such identifications.
The technology of radio frequency identification (RFID) involves a reader/interrogator station that transmits a
predetermined signal of inductive, radio or microwave energy to one or many transponders located within a
read zone. The transponder returns the signal in a modified form to the reader/interrogator and the data is
decoded. The data component in a portable gas or liquid cylinder environment provides the basis for
unambiguous identification of the transponder and may also provide a medium for a bi-directional interactive
exchange of data between the host and transponder. The signal may be modulated or unmodulated according
to architecture of the system.
In many cases it will be necessary or desirable to use one air carrier frequency and protocol, but this will not
always be possible or even desirable in all situations, and it may be useful to separate fundamentally different
cylinders by the response frequency.
However, there is benefit in using a standard common core data structure that is capable of upwards
integration and expandable from the simplest low cost cylinder identification system to more complex
functions. Such a structure will have to be flexible and enabling rather than prescriptive, thus enabling different
systems degrees of interoperability within and between their host systems.
The use of Abstract Syntax Notation One (ASN.1, as defined in the ISO/IEC 8824 series) from
ISO/IEC 8824-1 as a notation to specify data and its associated Packed Encoding Rules (PER) from
ISO/IEC 8825-2 is widely used and gaining popularity. Its usage will provide maximum interoperability and
conformance to existing standards and will meet the specifically defined requirements for a generic standard
model for portable gas cylinder identification in that it
⎯ enables and uses existing standard coding,
⎯ is adaptable and expandable,
⎯ does not include unnecessary information for a specific application, and
⎯ has a minimum of overhead in storage and transmission.
ISO 21007-1 provides a framework reference architecture for such systems. This supporting Part 2 provides a
standardized yet flexible and interoperable framework for numbering schemes. This part of ISO 21007 details
individual numbering schemes within the framework for the automatic identification of gas cylinders.
Central to the effective use of many of the constructs is a structure to provide unambiguous identification. This
part of ISO 21007 provides a standardized data element construct for the automatic identification of gas
cylinders.
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INTERNATIONAL STANDARD ISO 21007-2:2005(E)

Gas cylinders — Identification and marking using radio
frequency identification technology —
Part 2:
Numbering schemes for radio frequency identification
1 Scope
This part of ISO 21007 establishes a common framework for data structure to enable the unambiguous
identification in gas cylinder (GC) applications and for other common data elements in this sector.
This part of ISO 21007 enables a structure to allow some harmonization between different systems. However,
it does not prescribe any one system and has been written in a non-mandatory style so as not to make it
obsolete as technology changes.
The main body of this part of ISO 21007 excludes any data elements that form any part of transmission or
storage protocols such as headers and checksums.
For details of cylinder/tag operations see Annex A.
2 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 3166-1, Codes for the representation of names of countries and their subdivisions — Part 1: Country
codes
ISO 13769, Gas cylinders — Stamp marking
ISO 21007-1, Gas cylinders — identification and marking using radio frequency identification technology —
1)
Part 1: Reference architecture and terminology
ISO/IEC 8824-1:2002, Information technology — Abstract Syntax Notation One (ASN.1): Specification of basic
notation
ISO/IEC 8825-2:2002, Information technology — ASN.1 encoding rules: Specification of Packed Encoding
Rules (PER)

1) To be published.
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ISO 21007-2:2005(E)
3 Terms, definitions and numerical notations
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 21007-1 and the following apply.
3.1.1
bit rates
number of bits per second, independent of the data coding
3.1.2
carrier frequency
centre frequency of the downlink/uplink band
3.1.3
construct
one or more primitive constructs to form an ASN.1 message
3.1.4
data coding
coding that determines the baseband signal presentation i.e., a mapping of logical bits to physical signals
NOTE Examples are bi-phase schemes (Manchester, Miller, FM0, FM1, differential Manchester), NRZ and NRZ1.
3.1.5
modulation
keying of the carrier wave by coded data described in accordance with commonly understood methodologies
(amplitude shift keying, frequency shift keying)
3.1.6
octet
set of eight binary digits (bits)
3.1.7
power limits within communication zone
limits that determine the minimum and maximum values of incident power referred to a 0 dB antenna in front
of the tag
NOTE These two values also specify the dynamic range of the tag receiver. Power values are measured without any
additional losses due to rain or misalignment.
3.1.8
registration body
organization entitled to issue and keep track of issuer identification
NOTE For examples, see Annex A.
3.1.9
tolerance of carrier frequency
maximum deviation of the carrier frequency expressed as a percentage
3.2 Numerical notations
The numerical notations used in this part of ISO 21007 are as follows:
⎯ Decimal (“normal”) notation has no subscript, e.g. 127;
⎯ Hexadecimal numbers are noted by subscript 16, e.g. 7F ;
16
⎯ Binary numbers are noted by subscript 2, e.g. 01111111 .
2
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ISO 21007-2:2005(E)
4 Data presentation
4.1 General requirements
The data element construct determined in this part of ISO 21007 is an “enabling” structure. It is designed to
accommodate within its framework, data element constructs for a variety of GC applications, from simple GC
identification to more complex transactions with a wide variety of uses, and to allow combinations of data
elements to be used in a composite data construct. It is designed to allow as much interoperability of the data
elements within an electronic data interchange/electronic data transfer (EDI/EDT) environment as is possible
and has to provide a capability for a significant expansion of the number of GC applications in the future.
This part of ISO 21007 takes cognizance of and accommodates the operation of systems of different
capabilities and will enable within its structure the interoperability of one transponder in any country, even
though the operator systems themselves may be significantly different, so long as there is a common air
interface (at reference point Delta) and protocol. Even where information has to be collected by a separate
interrogator because air carrier compatibility does not exist, the data once collected is in a commonly
interoperable format and so may be used accurately and effectively within an EDI/EDT environment.
The data element structure defined in this part of ISO 21007 specifies the general presentation rules for
transfer of ASN.1 data schemes. It is also the purpose of this part of ISO 21007 to determine how ASN.1 will
be used for data transmission in GC applications.
Excluding transfers in a predefined context, the first level of identification required in ASN.1 messages
identifies the context of the message. This part of ISO 21007 determines that in GC applications this is
achieved by using an object identifier that shall be determined in accordance with an arc determined in
Annex B of ISO/IEC 8824-1.
The objective of this part of ISO 21007 is therefore to establish a basis where the message can always be
identified simply by reference to the relevant standard and without the requirement of central registration
authorities (except where those are specifically required in the referred to document).
4.2 ASN.1 messages
Where there is a simple message where no further subdivision according to ASN.1 rules is possible, the
message is called an ASN.1 “primitive message”. Such messages will have only one identification and length
2)
statement. The GC identification structure defined in Clause 3 of ISO 21007-1:— is an ASN.1 primitive
message.
4.3 Message identification requirements
The data constructs shall conform to ISO/IEC 8824-1.
With the exception of transfers in a predetermined context (see 4.4):
⎯ All GC standard ASN.1 messages shall commence with a unique object identifier that shall be determined
in accordance with the arc 2 (joint ITU-T), followed by the object class indicating a standard arc 0,
followed by the reference to the standard:
{ITU-T)(2)  standard(0)  standardxxx(yyy) }
⎯ Where the data content relates to standards produced by other identified organizations, they shall
commence with a unique object identifier that shall be determined in accordance with the arc 2 (joint ITU-
T) followed by the identification of an identified organization arc 3, followed by the identification of the
identified organization (as provided in Annex B), followed by the object class indicating a standard arc 0,
followed by the reference to the standard:
{ ITU-T(2)  identified-organization (3)  organization-identity(xxx)  standard(0)  standardxxx(zzz) }

2) To be published.
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ISO 21007-2:2005(E)
4.4 Predetermined context and the use of packed encoding rules
Where the context of a transfer is known, the data constructs determined in this part of ISO 21007 may be
assumed to be in accordance with the rules determined in ISO/IEC 8825-2.
In respect of any identification of an item using an ISO ASN.1 message, the data necessary for unambiguous
identification shall reside on the on-board equipment associated with the item being identified.
4.5 Sample GC data structure constructs
The ISO complete ASN.1 format is as follows:
octet 0 octet 1 octet 2 octet 3-4 octet 5-xx
02 20 00 ISO standard reference GC identification structure
16 16 16

The predetermined GC context follows:
octet 0-yy
GC identification structure

5 Gas cylinder identification structure
5.1 General requirements
The general requirement of the structure proposed shall be that it is constructed from one or more data
elements to form an ASN.1 message.
Each of these data elements shall be preceded by 2 octets that identify
a) the data scheme identifier (also referred to as DSI), and
b) the length of the data field.
Data scheme identifier (1 octet) Length of data field (1 octet) Data field

This part of ISO 21007 has been designed by adopting the principles of ISO/IEC 8824-1 and ISO/IEC 8825-2,
which utilize octets (bytes) of data elements to provide an application identifier, a coding identifier and a
length/use identifier in an “abstract syntax notation” for “open systems interconnection”.
By adopting the ISO/IEC 8824-1 and ISO/IEC 8825-2 abstract syntax notation with the inclusion of a data
element length indicator, the flexibility is provided for data elements of any length to be supported. This data
structure standard is itself given a migration path so that as technological developments allow further
capabilities, subsequent standards may provide additional data fields for use in all or some sector-specific
applications while maintaining the upwards compatibility from and to this part of ISO 21007.
The structure enables the chaining of multiple data elements from different application sectors to build
complex data element constructs. For example, a GC identification shall be followed by an ISO country code,
or perhaps a GC identification followed by a transient data set of the current contents, fill date and location
followed by a country identifier, etc.
It is expected that several data element structures will start with a GC identification data element.
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ISO 21007-2:2005(E)
5.2 Data structure construct
5.2.1 General
The data structure construct is as follows:
Data scheme Length of data Data field Data scheme Length of data Data field
identifier field identifier field

5.2.2 Data scheme identifier (DSI)
The octet used for the data scheme identifier shall be used to identify to which of the standardized GC coding
scheme data formats the data element construct conforms.
Each number issued shall be supported by an ISO format standard detailing the data scheme that is to be
used within that format.
NOTE Clause 6 details the initial list of primitive data scheme allocations.
5.2.3 Length
The length octet shall determine the number of octets in the subsequent data fields. It shall be a length
indicator as defined in ISO/IEC 8825-2.
NOTE For coding, this field will be kept to less than 127, i.e. 1-byte length is expected. For constructs, the extension
bit may be used to signify a 3-byte length indicator.
5.2.4 Data field
The data field shall follow the number of octets of data that comprises the data field as determined in the
previous octet.
The data structure of the data field shall be defined in a series of standard data formats issued and published
by the gas cylinder data scheme issuing authority and forming subordinate standards in support of this part of
ISO 21007.
NOTE This field may also contain constructs of primitives as defined in ISO/IEC 8824-1 and ISO/IEC 8825-2.
6 Gas cylinder identification data schemes
6.1 General requirements
The essence of the general requirement of GC systems is constructed around a basic core unambiguous
identification. This GC identification numbering scheme provides a “fixed” core unambiguous identification
element.
It is envisaged that this core element of unambiguous identification will form the first data set of one or many
data sets in a GC environment using data structures that comply with the structure established in ISO 21007-1.
Either data scheme 01 or data scheme 02 shall be used in accordance with 6.2 or 6.3, respectively. In
addition, data schemes 10, 11, 12, etc. can optionally be used (see Table 1).
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ISO 21007-2:2005(E)
Table 1 — GC primitive data scheme identifiers
Data scheme number Data scheme identifier GC data scheme
0 40 Nonstandard scheme

16
01 41 GC numbering scheme (binary)
16
02 42 GC numbering scheme (ASCII)
16

10 4A GC manufacturer information
16
11 4B GC approval information
16
12 4C GC package information
16
13 4D GC content information
16
14 4E GC commercial product information
16
15 4F GC production lot information
16
16 50 GC accessories information
16

20 54 GC acetylene specifics
16

This data structure is designed to be used not only as a form for simple GC identification, but to form the GC
identification element of all standard GC messages where GC identification is a component. To this extent,
while this part of ISO 21007 has been primarily designed for use in a transponder/interrogator environment, it
is expected that other GC systems, while they use different transmission media and effect similar data
exchanges, shall adopt this standard numbering scheme.
This compact numbering data scheme can be replaced or combined with a more versatile identification
scheme allowing the use of existing non-numeric gas cylinder identifications. This alternate unambiguous
identification data set will be given the DSI appellation: data scheme 02.
Other data schemes concerning the package and content of gas cylinders proposed in 6.4 to 6.11 provide
capability for other applications that simplify GC identification.
The data scheme identifier (DSI) is described in Table 1; the length is the number of bits of the information
field. Clauses 6.2 to 6.11 give some examples for the content of these data schemes. Clauses 6.2 and 6.3
describe the minimum definition for the unique identification number of a GC. The choice is between a binary
(6.2) and an ASCII (6.3) version. All other definitions in 6.4 to 6.11 are optional.

Data scheme identifier Length Information field/data scheme

Info 1 Info 2 Info 3 …….
Figure 1 — Flow chart for principles of 6.2 to 6.11
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ISO 21007-2:2005(E)
6.2 Data scheme 01: numbering (binary)
6.2.1 General
If data scheme 01 is used, the unique number shall be coded in binary format as indicated below.
The format provides a transponder code mandatory field providing specific adaptation to the requirements for
GC identification in the GC environment.
The code length is 64 bits or more and will be preceded by 2 octets that identify, respectively, the GC DSI
(i.e. 41 primitive) and the code length in octets (i.e. 08 or more).
16 16
The Data scheme 01 structure is as follows:
Data scheme identifier Length Unique number data field
41 08 or more
16 16

The third field contains the GC unambiguous identification number.
The following structure details the elements and content of the unambiguous data structure and is to be read
in conjunction with the notes shown following the structure.
Unique number data field:
ISO 3166-1 issuer country code Registration body Issuer identifier Service number / unique number

6.2.2 ISO 3166-1 issuer country code
The ISO 3166-1 issuer country code is as follows:
Bits Variables Type
(binary 0-4 095) 12 4096 Binary

6.2.3 Registration body
The registration body is as follows:
Bits Variables Type
(binary 0-15) 4 16 Binary

6.2.4 Issuer identifier
The issuer identifier is as follows:
Bits Variables Type
(binary 0-16 772 215) 24 16 772 216 Binary
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ISO 21007-2:2005(E)
6.2.5 Unique number
A unique number (within each ISO 3166-1 country) shall be allocated by a registration body (see Annex B).
Bits Variables Type
(binary 0-16 772 215 or more) 24 16 772 216 or more Binary

6.3 Data scheme 02: numbering (ASCII)
6.3.1 General
If Data scheme 02 is used, the unique number shall be coded in ASCII format as indicated below.
The format provides a transponder code mandatory field providing specific adaptation to the requirements for
GC identification in the GC environment.
The code length is 40 bits plus unique string length and will be preceded by 2 octets that identify, respectively,
the GC DSI (i.e. 42 primitive) and the code length in octets (i.e. 05 plus string length).
16 16
The Data scheme 02 structure is as follows:
Data scheme identifier Length Unique number data field
42 05 + string length
16 16

The third field contains the GC unambiguous identification number.
The following structure details the elements and content of the unambiguous data structure and is to be read
in conjunction with the notes following the structure.
The Unique number data field is as follows:
ISO 3166-1 issuer country code Registration body Issuer identifier Service number / unique number

6.3.2 ISO 3166-1 issuer country code
The ISO 3166-1 issuer country code is as follows:
Bits Variables Type
(binary 0-4 095) 12 4 096 Binary

6.3.3 Registration body
The registration body is as follows:
Bits Variables Type
(binary 0-15) 4 16 Binary

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ISO 21007-2:2005(E)
6.3.4 Issuer identifier
The issuer identifier is as follows:
Bits Variables Type
(binary 0-16 772 215) 24 16 772 216 Binary

A unique number (within each ISO 3166-1 country) shall be allocated by a registration body (see Annex B).
6.3.5 Unique string
A unique string provides a unique service/number issued by the operator. Strings should include alphanumeric
characters only, excluding accented characters or special symbols such as “ - ” or blank (i.e. 26 roman
uppercase alphabetic letters (A-Z) plus 10 (0-9) numeric characters) and shall be as follows:
Bits Variables Type
(8 bit characters ASCII string) 48 2 176 782 336 or more ASCII

6.4 Data scheme 10: cylinder manufacturer information (optional)
6.4.1 General
Data scheme 10 determines the form of the data field content, for GC identification for DSI 10 of ISO 27001-1.
The Data scheme 10 structure is as follows:
Data scheme identifier Length Cylinder manufacturer information data field
4A 40 or more
16 16

The third field contains the cylinder manufacturer identification number and the manufacturing serial number
of the cylinder.
The following structure details the elements and content of the data structure and is to be read in conjunction
with the notes following the structure.
The cylinder manufacturer information data field is as follows:
Manufacturer code Manufacturer serial number

6.4.2 Manufacturer code
The manufacturer code is as follows:
Bits Variables Type
(binary 0-65 535) 16 65 536 Binary

See Annex C.
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ISO 21007-2:2005(E)
6.4.3 Manufacturer serial number
The manufacturer serial number is an alphanumeric field allocated by the manufacturer and readable on the
cylinder (ISO 13769).
Bits Variables Type
(8 bit characters ASCII string) 4 8 or more 2 176 782 336 or more ASCII

Strings should include alphanumeric characters only, excluding accented characters or special symbols such
as “ - ” or blank. (i.e. 26 roman uppercase alphabetic letters (A-Z) plus 10 (0-9) numeric characters).
The recommended length of this DSI unique data element is 64 bits (with a 6-character manufacturer serial
number) or more.
6.5 Data scheme 11: cylinder approval information (optional)
6.5.1 General
Data scheme 11 determines the form of the data field content for GC identification for DSI 11 of ISO 27001-1.
The Data scheme 11 structure is as follows:
Data scheme identifier Length Cylinder approval information data field
4B 10
16 16

The third field contains information about the countries where the cylinder is approved.
The following structure de
...

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