CM Magazine

Card Durability Standards Revision

ISO/IEC 24789-1, 2 are the international standards for determination of card durability that is sometimes referred to as card service life. These standards were first published in 2012 after several years in development and have been in revision since their publication. These revisions are now in their final stages of approval, and it is expected that a substantially revised standard will be published later this year.

A primary objective of this revised standard is to provide a deterministic test plan for a particular card application and its intended usage. It relies less on long, sequential tests used in the current standards with substantial changes in both methodology and testing, utilizing enhanced technology and providing more clarity. However, test results still track well with comparable results from use of the current published standard.

In the current published standard, each age/usage combination corresponds to a card service life class. This provides a means for ranking and comparing the main factors affecting card service life. There are two sequential processes to generate an Application Profile: 1) first, defining three usage factors (environmental, storage and reader factors) and applying a probability for each condition and 2) from this generate what’s called the “raw application profile” (the first process). This raw profile is then “corrected” for usage frequency and card lifetime (the second process), which results in an Age and Usage Class. Once the application profile has been determined, it is necessary to define the set of tests to be performed. The standalone test method is where a single, untested card undergoes a specific test requirement. Basically, this method was for unembossed cards without chips (ICs). The evaluation sequence method is where the same card undergoes a series of tests in a specific sequence. So, in summary, this standard defines 1) a quantitative calculation of an “Application Profile” and 2) a set of tests to be performed appropriate for that determined Application Profile. However, it is left to the card issuer, and their testing lab, to determine the suite of tests that represent expected card usage in its intended application.

In the new, revised standard, as stated above, a primary objective is to have a more deterministic process for the suite of tests to be performed. The premise is that two, or more, independent test labs come to the same conclusion of the appropriate test suite. Test parameters for most methods to be included in a test plan suite are determined from card functional elements, the number of uses per day and expected lifetime (years). Test sequences in the test plan have been shortened with a limit of three methods in any test sequence. Test parameter calculations are only based on the usage factor (uses/day) and expected lifetime (years). The complex calculations using environmental, storage and reader factors of the current standard have been eliminated.

A correlation study was done to compare results of the new revised version with the published 2012 version of ISO/IEC 24789-1. It shows good correlation (mathematically) from the 2012 standard to the revised implementation on age (linear correlation) and usage (exponential correlation) classes (the respective correlation curves are a simple best fit curve between the data points used in each version of the standard). Thus, they are an approximate estimate of how to correlate the published 2012 age/usage classes to the new revision of the standard. Also, new to the revised standard is the that the test plan setup for personalized cards and card bodies are separately defined. The text recommends testing fully personalized cards but does not require them. This allows both a card manufacturer to test un-personalized blanks and allows personalization companies to conduct testing using cards that they have available. It drops requirements for testing finished cards but recommends their use whenever possible.

Some changes in the tests themselves are also included. Most notably, the temperature and humidity cycling method has been replaced by temperature exposure with humidity variation method. DOTP replaces DOP as the plasticizer material used in the plasticized vinyl storage test method. The temperature and humidity aging followed by peel strength sequence testing has been eliminated. Wear and soil (now called “Soiling Test” with a new apparatus and method), UV light exposure and shortened bending stress tests have been moved to an informative annex as optional test methods. Also, new mechanical life cycle sequence test method and apparatus for contactless IC cards, card static stress and temperature and humidity induced dye migration test methods have been added as options in the annex. Standalone and sequence tests are also more fully described and explained.

Overall, most tests have been enhanced to take advantage of improved technology since the published 2012 standard. Improved clarity of test methods with better diagrams also enhance understanding of the standard. Undoubtedly, this revised standard will also undergo further revisions over time as technology and knowledge improve. However, this revision achieves its primary goal of providing certainty of test regimes for defined card applications and their usage, that is a significant advance over the current published standard.

About the Author: David Tushie, ICMA standards and technical representative, has had a long and continuing career in the card industry, working for international companies such as DataCard, UbiQ and NBS Technologies. He has masters’ degrees in engineering and business, holds U.S. and international patents in measurement and card issuance systems and has had several years of involvement with the ANSI, INCITS and ISO Standards process. ICMA is represented at six ISO and ANSI Standards Meetings through David’s standards role within the association.