Awards & Engraving

September '16

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26 a-e-mag.com • A&E SEPTEMBER 2016 People ask how they know which colors are light and which are dark, since there isn't any guidance in the code. The best way to do it, according to most scien- tists dealing with the topic, is by looking at the light reflectance value (LRV) of each color. You can now purchase a portable instrument for $500 or less to measure the LRV, and in many cases, if you are using a colored material or a paint, the manufac- turer will gladly supply it. Once you know the LRVs of two colors you want to use, the simplest thing is to be sure that the two numbers are as far apart as possible. If the light color is in the top half of the scale (50-100) and the dark color is 15 or less, you will have minimum adequate contrast according to many building codes. Some studies have shown that a 70-point difference will provide quite good contrast for over 90 percent of people with serious vision conditions. CHARACTER DIFFERENCES But let's return to the characters them- selves, because the differences between tactile and visual characters are important. While visual readers need large, upper and lower case characters with bolder strokes, tactile readers usually benefit when the characters are somewhat smaller and have thin beveled or round profile strokes. It's important to use all upper case, and to space the characters quite widely so that it's easy to feel the point where one char- acter ends and the next one begins. Obvi- ously, contrast is not an issue at all, nor is glare. You can "hide" the tactile characters and braille in a decorative footer at the base of the visual sign. You can even use shiny metal as long as the area with the visual characters isn't impacted by the glare. If you are a detail person, you might want to know some of the specific rules. They differ slightly for tactile and visual characters, but the major points are that tactile characters are uppercase, and that they range in height from 5/8 inch to 2 inches (and please, if you are making a dual purpose sign, keep the tactile char- acters small). Be sure there is a minimum 1/8-inch space between the two closest points of adjacent characters, measuring at the top surface of the characters, not the base. The visual spacing can be much less, as little as 1/16 inch if the characters are beveled or rounded. This sign was also designed as a result of a lawsuit. The wood and chrome trim picks up the décor of the building, and an insert can be changed if the tenant changes. The tactile information is unobtrusive but highly readable by touch. An interesting dual purpose sign for the Los Angeles Metro System, with the tactile message on top of a longer, more detailed visual message and pictogram. When viewed straight on, the pictogram is not distorted.

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