As AIDC applications become more and more critical to a company's success, the cost of bar code scanning failure becomes more significant. Such giant merchandisers as Wal-Mart, for example, have become famous for leveling whopping fines of $50,000 or more on suppliers whose product labels repeatedly misread. Consequently, bar code verification systems, once exclusively used by printers and label vendors, are now commonly used for on-site printing. Verifiers will grade a symbol unacceptable or by degrees of acceptability based upon ANSI's published criteria, known as the Bar Code Print Quality Guideline. Verification devices can be integrated in-line, attached to the printer while monitoring the quality of every printed label or they can be used in a standalone configuration to audit batches of labels. In either case, verification can?t completely eliminate bar code performance problems. Verification can, however, provide a quantitative measure of print contrast and derive wide-to-narrow ratios, checking printed symbol conformance against symbology print quality standards.