He adds that both PVC and polycarbonate are typically considered various applications it will support. The second part uses this among the more rigid card materials. determination to define a series of tests to evaluate if it can meet Cards with embedded electronic components may have a shorter this prescribed lifespan. lifespan based on that fact alone, McGoran says. “With contact, Think of it this way, the demands on a passport card used infrecontactless and dual-interface cards, our experience and testing quently for international travel are far less than those placed on a have shown that the durability of the internal fare collection card used multiple times each components, circuitry and connections can day for public transport. Still the required BLENDED CARDS SUCH AS significantly affect card life longevity,” he lifespan for a passport card is far longer than explains. PVC AND POLYESTER BLENDS that of a transit card, so this too must be taken Still, maximizing lifespan is the goal and into consideration as tests are designed. TEND TO RESIST CRACKING composite cards made with different materiANSI INCITS 322: This defines a Card DURING REPETITIVE FLEXURE Structural Integrity Test to help gauge a als have the best durability, says McGoran. TESTING BETTER THAN PURE card’s resilience against delamination under “Blended cards such as PVC and polyester blends tend to resist cracking during repetiadverse environmental conditions. The test PVC CARD STOCK tive flexure testing better than pure PVC card is considered rigorous or extreme, and used stock,” he explains. “We have observed this most often as a qualitative or comparative often translates to longer service life in the field for these blended assessment between different card constructions. cards versus pure PVC card bodies.” To conduct one of the ANSI INCITS 322 tests, cards are placed Polycarbonate cards are popular for European credentialing into a one-gallon paint can along with “dummy cards.” Thirtyprojects, Ogden says. “But polycarbonate isn’t the only answer,” milliliters of distilled water and 10 grams of sand are added, she explains. “There are other substrates out there that are more and the can is sealed and mounted into a standard paint shaker cost effective and could be used with both local and central issusimilar to the machines used at hardware stores. The cards are ance applications.” then shaken for three hours, removed and rinsed. The cards are “These alternatives can also be as or more secure and durable generally considered satisfactory if they do not delaminate or than all-polycarbonate cards because of their increased chemical peel apart. If they include an integrated circuit chip, this should resistance, abrasion resistance and flexibility,” says Scaglia. still be functional. This test has proven to be quite revealing for the various card STANDARDIZING CARD DURABILITY materials and structure technologies used by card manufacturers. Many cards come out of the shaker with only worn corners, but There are several facets to card durability. A primary consideration some cards simply disintegrate or separate into their component is the mechanical durability of the card body, which includes charlayers. acteristics like bending and stiffness, peel strength and resistance to chemicals, says Brad McGoran, principal engineer at Exponent, ANSI INCITS 322 SURFACE ABRASION TEST a consultancy that performs card testing. Additionally, there are the durability characteristics of the To conduct the Surface Abrasion Test, two cards are mounted printed and laminated features on the card. These include the on a machine that rotates them below a pair of abrading wheels abrasion resistance of the magnetic stripe or printed barcode, or grinders of prescribed weight and grit rating. The machine is the resistance of the printed dye to smear or drift, and the UV stopped every 250 rotations and a resurfacing disk with a preresistance of the printed surface, McGoran explains. scribed grit rating is used to resurface the abrasion wheels. After If the card includes an integrated circuit chip with a contact pad every 500 cycles the cards are photo documented. This process or a contactless antenna, durability issues also revolve around continues until the cards reach 5,000 cycles. The estimated point the resilience of those features. For example, the card should of print breakthrough is tracked and recorded. maintain functionality after exposure to x-rays and magnetic fields, and it should survive anticipated levels of electrostatic A CARD ISSUER CAVEAT EMPTOR discharge exposure. For each of these areas, internationally recognized standards When it comes right down to it an issuer has to look at the use of bodies have developed a series of testing methods. Test labs implethe credential. “In our experience, there is no one single formula for ment these prescribed procedures to provide unbiased analysis of the best and most durable card body construction since different a specific card construction’s durability and likely longevity. Key blends and formulations are best suited to different environments test standards include ISO 24789 and ANSI 322. and usage scenarios,” McGoran says. “We recommend that issuers ISO/IEC 24789: This standard is made up of two parts. The and their card manufacturers run specific tests to evaluate overall first is a methodology for determining a card’s expected lifespan durability of the card body to ensure that fielded cards meet their taking into consideration the demands placed upon it by the designated life expectation.”
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