Specimen Barcode and Labeling Guide

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Specimen Barcode and Labeling Guide

(Nov 7, 2014 DRAFT)
This guide aims to provide information about what a barcode is and isn't, how it should be used, what equipment to use to read and manage barcodes and what best practices exist for different collection types (e.g., wet, on a pin, on a sheet or packet). This guide will not discuss at any length RFID tags. They may be useful in managing aisles, cabinets, shelves, drawers and carts but are not likely to be cost-effective for individual specimens. A questionnaire to collected information was sent out in early November to the idigbiodigi-l list serv.

Definition

From the perspective of biodiversity specimen collections and this guide, a barcode is an optical machine-readable encoding of a unique identifier that is attached to a specimen. A barcode is used to efficiently manage specimens and to quickly locate them in the specimen database. A barcode reader scans the encoding and because the barcode is part of the specimen database record, the record can be called up and used in collection management tasks, for example, when re-locating specimens or processing loans. Additionally, using a barcode reader to enter the code into a new database record, or to query for an existing record means that mistakes in barcode entry are essentially eliminated.

Character encoding

1D barcodes

  • Code 128
  • Code 39 (also known as Alpha39, Code 3 of 9, Code 3/9, Type 39, USS Code 39, or USD-3) is a widely used, variable length, discrete barcode symbology.
  • Code 49

2D barcodes

  • Data Matrix code is a two-dimensional matrix barcode consisting of black and white cells arranged in either a square or rectangular pattern. The information to be encoded can be text or numeric data. Usual data size is from a few bytes up to 1556 bytes. The length of the encoded data depends on the number of cells in the matrix. Error correction codes are often used to increase reliability: even if one or more cells are damaged so it is unreadable, the message can still be read. A Data Matrix symbol can store up to 2,335 alphanumeric characters.
  • QR code

Barcode labels

The label material

Sheets and packets

If a label is to be attached to the specimen as in the case of an herbarium sheet, it must be acid-free in content and fixative, and should be placed in a uniform location (as much as possible given the exigencies of a pressed plant arranged and glued to a sheet) to aid in rapid processing.

Wet collections

The best material for wet collections is a spun bound polyester label medium used with wax/resin ribbon and a thermal transfer printer (Datamax, Zebra etc.). Print quality is excellent and barcodes can be generated from collections management systems for printing and reading on labels.

Pinned specimens

Others

In the case of unit trays, drawers, skins

What's printed on the label

The text printed on the barcode label is not always only the encoded characters, sometimes it includes other identifying information about the specimen, such as institution and collection name. The barcode designer should pay special attention to distinguishing between the code itself and the information printed on the label. A good barcode contains the least best information, in order to not have to replace the barcode if the included information changes, such as taxon, and other provenance details from the label. A unique identifier, possibly with the specimen collection code and institution code are a good minimal place to be. It might be helpful to reproduce the code itself in visible human-readable characters, but care should be taken to not add extraneous text that might be confused with the encoded information. This duplication can be useful when a barcode reader is not handy for checking a specimen against its database record.

Barcode readers

A barcode reader or scanner is sometimes called a 'wedge'. The Symbol scanner (http://www.motorolasolutions.com/US-EN/Business+Product+and+Services/Bar+Code+Scanning/General+Purpose+Scanners/Handheld-Scanners/LS2208_US-EN) is a good all around reader according to some sources.

Barcode printers

In order for a barcode reader to read the encoding on the label, it must be legible for the lifetime of the specimen. That means it must be produced on a quality printer whose ink will not smudge or deteriorate over time, and printed on label stock that will not degrade in its environment (e.g., in a wet collection), or the faster than the specimen paper it is attached to (e.g., herbarium sheets).

Examples

Wet collections

Datamax thermal transfer printer printing on spun bound polyester with wax/resin SDR ribbon. Sold from Alpha Systems (http://www.alphasystemsva.com)as museum solution.

Pinned collections

Herbarium sheets and packets

Why some institutions have chosen not to use barcodes

Below are some anecdotes directly from institutions who have chosen not to use barcodes on their specimens:

  • Currently at SBMNH invertebrate zoology we do not use barcodes on specimen labels. We see loan processing as the primary use of barcodes. While we do have dozens of loans per year, the added effort to integrate a barcode system into our cataloguing scheme is not worth the time/cost to implement at this time.”
  • KU Ichthyology has chosen not to use barcodes due to the cost per unit effort being too high. Due to the fact that we only use barcodes for processing loans and inventories and process relatively small loans of material, the cost of adding barcodes to every jar (43,000 of them) far outweighs the gain achieved. Andy Bentley (abentley@ku.edu)

Labels and Labeling

References and Resources