2009 Edition Part 6 Figure 6F-6. Advance Warning Arrow Board Display Specifications
Figure 6F-6. Advance Warning Arrow Board Display Specifications
This figure illustrates advance warning arrow board display specifications.
On the left side of the page is the heading "Operating Mode." Three operating modes are shown, with the representative advance warning arrow panel displays shown as yellow dots on a horizontal rectangular black background on the right side of the page under the heading "Arrow Board Display (Type C arrow board illustrated)." Below the above heading on the right side of the page is the notation "(Right arrow shown; left is similar)."
Under "Operating Mode," the first heading is "I. At least one of the three following modes shall be provided:" Under that heading, the following listings are shown under "Operating Mode," with accompanying illustration and text under "Panel Display."
- "Flashing Arrow": A panel display is shown of a horizontal arrow pointing to the right, with a shaft composed of five yellow dots leading to an arrowhead composed of five yellow dots. A note under the panel display illustration states: "Merge Right."
- "Sequential Arrow": Three separate illustrations of panel displays are shown, each displaying a horizontal arrow pointing to the right, with an arrowhead composed of five yellow dots. The shafts of the arrows in the three separate illustrations are composed of two, three, and five yellow dots, respectively. In each of the three illustrations, the left-most yellow dot of the arrow shaft is located near the left edge of the panel and the arrowhead is just to the right of the right-most dot of the shaft. A note under the panel display illustrations states: "Merge Right."
- "Sequential Chevron": Three separate illustrations of panel displays are shown, each displaying one or more chevron arrows pointing to the right, with each chevron arrow composed of five yellow dots. In the first of the three illustrations, one chevron arrow is shown, located at the left side of the panel. In the second illustration, two chevron arrows are shown, located at the left and center portions of the panel. In the third illustration, three chevron arrows are shown, located at the left, center, and right portions of the panel. A note under the panel display illustrations states: "Merge Right."
Under "Operating Mode," the second heading is: "II: The following mode shall be provided: Flashing Double Arrow." Under the heading "Panel Display," a double-headed horizontal arrow is shown composed of three yellow dots in a horizontal line with each arrowhead composed of five yellow lights. A note under the panel display illustration states: "Merge Right or Left."
Under "Operating Mode," the third heading is: "III. At least one of the following modes shall be provided: Flashing Caution or Alternating Diamond Caution." Under the heading "Panel Display," three separate illustrations are shown, separated by the word "or." The first illustration shows four yellow dots, one near each of the four corners of the display panel. A note under the panel display states: "Flashing Caution." The second illustration shows a horizontal row of four yellow dots. A note under the panel display states: "Flashing Caution." The third illustration shows a diamond composed of eight yellow dots at the far left of the panel and a second diamond at the far right of the panel. A note under the panel display states: "Alternating Diamond Caution."
A table shows the following—minimum size, minimum legibility distance, and minimum number of elements—for the four Arrow Board types:
- Arrow Board type A: minimum size 48 x 24 inches, minimum legibility distance 1/2 mile, and minimum 12 elements.
- Arrow Board type B: minimum size 60 x 30 inches, minimum legibility distance 3/4 mile, and minimum 13 elements.
- Arrow Board type C: minimum size 96 x 48 inches, minimum legibility distance 1 mile, and minimum 15 elements.
Arrow Board type D: minimum size "None" (note: length of arrow equals 48 inches, width of arrowhead equals 24 inches), minimum legibility distance 1/2 mile, and minimum 12 elements.
