Label Implementation Guide (LIG)
Implementing a GS1 System
This chapter uses terms and concepts presented
in Chapter 7 and Chapter 3 and it
further assumes that the preparation steps outlined in Chapter
4 have been completed. If you are not familiar with the GS1 System and
bar code printing, you may want to read Chapter 3 & Chapter 4 before
continuing with this chapter.
This chapter explains how to label consumer units
with the GTIN-12 and / or intermediate packs with the GS1-128. Chapter
6 deals with implementing a Serial Shipping Container Code project.
On the surface, the request to implement these
projects appears to be simple … get the bar codes shown below on your products
and your intermediate packs and shipping containers.
In practice, however, the request initiates
The first step of these sub-projects is
understanding what the customer is asking for. Some companies want the GTIN-12
(encoded in a UPC-A bar code) placed on individual items but are not asking for
the GTIN-14 to be encoded in an originally referenced ITF-14 or GS1-128
(formerly UCC/EAN-128) bar
code. Step 1 then is to confirm what the customer is asking for:
GTIN-12 number only. Covered in this chapter.
number only (Note: this would be very unusual). Covered in this chapter.
the GTIN-12 number and the GTIN-14. Covered in this chapter.
Serial Shipping Container Code (SSCC). Read Chapter
to the ANSI MH10.8
Once the scope of the request is understood,
several additional sub-projects can be defined:
Get a GS1 Company Prefix (see Section 4.8).
Assign UPC-A Global Trade Item Numbers (GTIN)
to all products. (Since this would be held in a data file it will be a 14 digit
global trade item number (GTIN) See section 4.2
GTIN-14 numbers (14-digit) to all intermediate packs and shipping
database and software to recognize the new numbers.
necessary, layout new graphics on packaging, making room for bar codes.
Print and apply the UPC-A bar codes with GTIN-12 numbers to
Print and apply the ITF-14 or GS1-128 bar codes with GTIN-14
numbers to all intermediate packs and cartons.
these numbers to your customers.
Assigning GTIN-12 numbers to all products
(refer to the documents provided with the GS1 Company Prefix)
The GTIN-12 is assigned by
the manufacturer to each of its products. The 12 digit item number is a subset
of the 14 digit GTIN. So, if you have not yet assigned any 12 digit GS1 numbers,
then start with a 14 digit GTIN for each item. The relationship is explained in
section 4.2. And demonstrated in section 5.4 below. To assign this number to
your products, follow these steps:
As a rule, these numbers
should be assigned arbitrarily, without attempting to reserve blocks of numbers
for special colors or sizes or assigning any significance whatsoever to the
number. Building so-called "intelligence" into numbers frequently causes more
problems than it solves.
Getting a Company Prefix from the GS1
Contact GS1, formerly the Uniform Code Council (UCC),
to get a Company Prefix. The GS1 Customer Service Department in Dayton, OH
assigns the Company Prefix and maintains a database assuring that no other
company is assigned the same number. Applicants should access the GS1 website at
www.gs1us.org and apply for
Assigning GTIN-14 Numbers
is a 14-digit number assigned by the manufacturer to each standard packaging
level unit above the consumer unit. To assign this number, follow these steps:
- Make a list of the different standard
intermediate packs and shipping container for each consumer unit identified
Note: Many companies do not ship their
products in standard configurations. In these cases, it may be necessary for the
project team to establish standard shipping configurations for all its consumer
units (or just the ones shipped to the customers asking for the SSCC) in order
to assign them GTIN-14 numbers.
- Assign Indicator digits to
each different standard packing configuration. Use the numbers 1 through 8. The
Indicator of "0" can be used in special situations where the shipping container
is also the lowest unit of sale, i.e. a bathtub. The Indicator Digit is the
first, or left most, digit in the 14-digit GTIN-14.
- Add a leading zero to the
eleven digit GTIN-12 base number of the product in the intermediate pack or
shipping container, i.e. If the GTIN-12 number for the product is 098756100013,
strip off the last digit (3) and add a zero to the front. The UPC-A base number
- Create a 13-digit number
by combining the Indicator digit assigned in step 2 with the GTIN-12 base number
calculated in step 3.
- Complete the 14-digit
number by calculating the check digit as the fourteenth, or right most, digit in
the 14-digit GTIN-14.
Preparing the database and application software
Using the GS1 System does not mean
abandoning present numbering systems. Usually it means adding the ability to
cross-reference the new numbers to the old. The table below illustrates this:
A … Record
Number… is for reference purposes only.
B … Full Global Trade Item Number (GTIN)… is the new term for
the 14-digit data structure to identify trade items (products and services) with
the GS1 System.
- Even though the GTIN-12
number is only 12 digits, it is stored in a 14 digit, all numeric, right
justified, zero-filled field to make it consistent with the GTIN-14 number
format. Padding the number with leading zeros does not change the check digit
- Column C … Original UPC
Number … is now the GTIN-12 number of the item.
- Column D… Old # …
is the company’s "old" internal product number (and may still be the
current product number).
- Column E … Description
… is the description.
- Column F … Quantity
… is the quantity of "Consumer units" defined by the left most number in column
Digit Product Code (GTIN)
Original UPC-A Number
1 Single Red Pen
1 Single Red Pen
1 Single Red Pen
Red Pen 5-Pack
Red Pen 5-Pack
Red Pen 5-Pack
Line #1 is a single
"Consumer unit" Single Red Pen. Lines 2 & 3 are the same product in different
standard shipping configurations. Note that the first three line items have the
same Original UPC-A Number in Column C.
Also, note the Indicator
digits (Indicators 3 and 5 respectively) in the left-most position of the
GTIN-14 column in lines 2 & 3. These indicate different package quantities of
the same consumer units. When the GTIN-14 for line #2 is scanned, the inventory
will be adjusted (incremented for a receipt, decremented for a shipment) in the
amount of 50 Red Pens with the Original UPC-A Number 098756100013.
The GTIN-14 is precise and
it will work better with EDI (Electronic Data Interchange) transactions because
the quantity is explicitly tied to a specific number. Transmitting the GTIN-14
alone will communicate product and quantity information.
Line 4 is the same product
in a 5-Pack container instead of a single item package. It is assigned a
In the example above, the
following actions were necessary to add the ability to recognize the GTIN-12
- Add two new fields to the
data base. One for the GTIN-12 number and the other for the GTIN-14.
- The UPC-A bar code is
formatted as 12 digits, all numeric, right justified.
- The GTIN-14 is formatted as 14 digits, all
numeric, right justified, zero filled.
The next step is cross-referencing the new field
to the old item number. The objective is to enable the existing business system
to locate the proper database record when either the Original UPC Number or the
new, GTIN-14 is entered.
Note: The numbers might be key entered or bar
code entered but the system won’t necessarily know the difference. For the sake
of accuracy, some programmers design their programs to force bar code entry of
critical data elements because scanning bar code is more accurate than manual
key entries. However, this is not the rule and it is totally optional. In most
cases, the computer will treat bar code data entry the same as keyboard data
Companies without their own computer departments
should contact their primary software vendor to determine their present system’s
capabilities to cross-reference several numbers to the same inventory record. It
is important to recognize that the changes that need to be made have nothing to
do with the technology of reading bar codes. The changes are related to
cross-referencing several numbers to the same inventory record. The fact that
the number may be entered via a bar code scanner is totally irrelevant. The
question for the primary software vendor is: Can your system cross-reference
several numbers to the same record? Bar code has nothing to do with it.
Once the system has the capability of
cross-referencing several numbers to the same inventory record, the applications
that will need to accept either the old numbers or the new numbers will need to
be identified and modified accordingly. This usually falls on the shoulders of
the company IT (Information Technology) or computer department or the company’s
primary vendor of its business system software. The affected applications /
modules would probably include:
- Order entry
- Order picking
- Inventory Adjustments
- Shipping Verification
Alternately, instead of
getting the present software vendor to modify their program, third-party
programmers could write a custom program to accomplish the same thing but this
approach should be considered very carefully. If the primary information system
is updated or revised by the vendor, the custom program may not work with the
new version. Generally speaking, it’s safer to get the primary vendor to make
the necessary adjustments and commit to keeping the program capable of
cross-referencing several numbers to the same inventory record.
5.5 Printing and applying
GTIN-12 numbers in the UPC-A symbology
Once the numbers have been
assigned and the computer system can recognize the new numbers and the old, bar
codes representing these numbers will need to be printed and applied to the
company’s items and, if specified, intermediate packs and shipping containers.
Chapter 7 … Bar Code
Print Quality for a detailed explanation of printing alternatives.
The project team will need to
decide how the UPC-A symbols will be printed and it will also need to establish
quality control procedures to verify that the bar codes are printed and applied
according to the specification.
UPC-A symbols can be printed
directly on packaging with offset, flexographic or silk screen technologies.
They can also be printed on labels and applied to the product manually or with
automatic label applicators.
The decision to use one print
method or the other is based on a variety of factors including volume of labels
/ symbols needed, the packaging’s compatibility with direct printing methods,
the company’s ability to forecast its requirements ahead of time and the
company’s willingness to assume responsibility for the quality of the symbol
in every respect.
See the discussion on bar code print
quality in Chapter 7.
speaking, direct printing on packaging is the least expensive for very large
quantities. Printing labels in-house requires less lead time and allows quick
response to unexpected label requirements (usually at a higher per unit cost).
Printing and applying the GTIN-14 number in the ITF-14 or GS1-128 Symbol
If the customer is requesting the
GTIN-14 number on intermediate packs and shipping containers, methods of
printing and applying these will also need to be selected and procedures to
verify quality will need to be written.
7 … Bar Code Print Quality for a detailed explanation of printing
numbers can be directly printed on corrugated cartons using the Interleaved 2 of
5 (ITF-14) symbology. Direct printing methods save the cost of labels which can
be significant over a year. Label costs vary with quantity, label materials and
label size but a 10 sq. in. label (2.5" x 4") would cost between 1˘ and 2˘ in
quantities of 100,000 or more. Cartons can be direct printed off-site, usually
with offset printing technologies or on-site using ink jet technology (at a
likely higher per unit cost).
The GS1 has revised its specifications
allowing the GTIN-14 number to be encoded in GS1-128 symbology instead of
ITF-14. When using this new format, the 14 digit number is preceded by the
Application Identifier "01" which tells the computer the bar code contains the
GTIN-14 number. See Appendix 5 for a complete list of Applications Identifiers
The GS1-128 symbology cannot be reliably printed directly onto cartons because
of unpredictable ink absorption rates. Choosing this symbology and format
usually means choosing labels instead of direct printing.
One final point, although the GS1 has defined this method of communicating the
GTIN-14 number, not all companies are accepting it. Check with the customer
before selecting this symbology and format.
is especially important when printing directly on corrugated cartons because ink
spreads at an unpredictable rate on different lots of corrugated cartons. If the
ink spreads too much, the bars become too wide and the spaces too narrow. Bar
codes printed directly on to corrugate should be checked periodically with an
ANSI/CEN/ISO-capable bar code symbol quality verifier.
printing alternatives include thermal transfer, laser, impact printers, and
possibly ink jet printers.
5.7 Communicating the
GTIN numbers to the customer – data
may already have procedures in place to communicate your existing numbers to
your customers but if your database structure is different or if the customer
needs a specific structure or file format, some type of field mapping will be
necessary. Although some people still use hard copies of catalog information or
send files on CD, the direction is clearly to use the Internet to send and
receive information. The best methods enable information to be transferred in
the transfer method, companies must understand which element of information is
contained in each position in the record. Companies in your industry have
developed a model Standard Item
Record (SIR). The model defines each element of information and
represents it in an Excel spreadsheet.
Not only is it
necessary to communicate the SIR to your customer(s), it’s also a good idea to
submit printed samples of your printed bar codes to the customer to make sure
they can read them. Some customers insist on this anyway. Considering the cost
implications and possible negative impact on customer relations if they can’t
read the bar codes you send them, it’s a good idea to get the customer to
respond in writing, stating their acceptance of the sample. It’s important to
remember, however, that ongoing print quality inspections will be needed at your
end to assure that printing systems continue to produce high quality,
5.8 Summary List of Tasks and Milestones
Determine what your customer(s)
is / are asking of you, i.e. understand the specification.
Get GS1 Company Prefix from the
GS1 Organization. The Company Prefix is part of GS1 membership.
Make a list of all your
"consumer units" and assign GTIN-12’s to each one.
If you are being asked to mark
intermediate packs and shipping containers with the GTIN-14 and ITF-14 or
GS1-128 bar code symbologies, make a list of all your standard packaging
configurations for each consumer unit and assign a GTIN-14 number to each
Cross-reference the new GTIN-12
code to your old numbers in your computer database and modify applications
to recognize / accept the new numbers or the old numbers.
Decide how you want to print
each type of bar code, i.e. how you want to print the UPC-A symbology at
item level and how you want to print the ITF-14 or GS1-128 symbol at higher
levels of packaging.
Design label formats for each
customer. Do this yourself or have an outside vendor do it as an item of
their contract. Note that your customers may have specified label formats
Submit sample bar codes to your
customers for written approval.
Print and apply bar codes to
your items and higher packaging levels.
Communicate these numbers to
Develop and implement quality
control procedures to assure that your print quality and bar code placement
remains in specification.
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