Excerpt from RATIONALE STATEMENTS REGARDING ISSUES COMMON TO ANSI Z535.2 and Z535.4 January 30, 1989

Historically, ANSI standards addressed public and in-plant safety signing (Z35.1 and Z35.4) but not safety messages that were to be affixed to products. These product hazard alerting labels had to be adapted from one of a number of standards, ANSI as referenced above, but also from other voluntary consensus organizations such as SAE, as well as individual company and industry standards. The task of the Z535 committee was to combine these into one basic standard if possible and work began along these lines.

After a period of time, during which a number of meetings were held and ideas exchanged from many sectors, it became evident that environmental safety signs and product safety signs had distinctly different user groups with different requirements.

Environmental safety signs are usually larger, observed at longer distances, frequently contain less information for visual clarity at a distance, and are not likely to visually blend with colors in the background. Product safety signs are likely to contain more information within a smaller format, are usually observed at closer distances, must integrate with a wide range of product sizes and shapes, and should always contrast with the product color.

Thus, the design and color characteristics of product safety signs are different from those of environmental safety signs. The Z535 committee determined that not only should it be permissible to have two different standards, but desirable, in order to tailor each standard to specific needs.