Statutory Signage
In signage, a pictogram is the image used to convey the message of the sign. In statutory signage pictograms follow a very specific set of colour, shape and sizing rules. In UK and EU signs the width of a sign's pictogram is set at 80% the height of the area it is printed to. In the US, a pictogram that identifies a room or space (such as the gender pictogram on a restroom signs), must follow specific rules. Other pictograms that must comply with rules are the four "Symbols of Accessibility" specified in the ADA Accessibility Guidelines.
For example: On an A4 Portrait UK / EU statutory sign (210 x 297 mm) using 2/3s of its area to display the pictogram 210 w x 198 H (mm) and 1/3 for its text display, the pictogram would be 158.4 mm wide. (80% of 198 mm).
In the US, the pictogram described above would have to be located within a 6-inch-high (150 mm) clear field, with raised characters and braille located beneath the field.
For a pictogram to work it must be instantly recognizable and understood by all. For this to work the image must be kept consistent. In its purest form a pictogram on a sign should be understood even if there is no text present. Following the standard color and shape rules increase the likelihood of a universally understood pictogram and therefore sign.
According to the book "Discovery-Based Retail," signage falls into three groups: decorative, adding eye-pleasing color; informational; or directional, providing guidance.
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