Chapter 3 Bar Codes

Quiet Zone

The bar code structure requires a completely blank quiet zone which extends

4.75inches from the right edge of the mail piece. In addition, a minimum quiet zone of 0.040-inch above and below the bar code data must also be provided. You must provide sufficient space for this zone.

Start/Stop Code

The start and stop codes are referred to as “framing bars” in POSTNET. The start and stop codes are each one tall bar, one identifying the leading and trailing end of the bar code. The start/stop code is automatically produced with each bar code. The start/stop code structure permits bar code scanning in a left-to right direction only.

Data Field

The bar code data produces a single field of 30 bars for a 5-digit data field, 50 bars for a 9-digit data field, or 60 bars for an 11-digit data field. The bars are grouped in sets of five. Each set of five bars (comprised of two tall bars and three short bars) represents one of the five digits of the zip code, plus the four-digit zip code extension. If the Advanced Bar Code is used, an additional two-digit code is also added to make an 11-digit data field.

Each bar width is equal, and must be .020-inch ± .005-inch. Each bar height is either a tall (full) or short (half) bar, representing a 1 or 0, respectively. Each tall bar must be .125-inch ± .010-inch; each short bar must be .050-inch ±

.010-inch. Horizontal spacing between bars (pitch) must be 22 bars ± 2 bars per inch over any 0.50-inch portion of the bar code. Horizontal spacing at 24 and 20 bars per inch is 0.0416-inch and .050-inch, respectively, with a clear vertical space ranging from 0.012-inch to 0.040-inch between bars.

Check Digit

The sixth, tenth or twelfth digit represents the automatic check digit character for the 5, 9 or 11-digit data field, respectively. The check digit is added automatically to verify accurate scanning.

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Printronix LQH-HWTM manual Quiet Zone