| Character Height and Viewing Distance |
 |
| Signs should be sized according
to the expected viewing distance and the time needed for the observer
to avoid the potential danger. We recommend that the size of the sign
be determined by letter height of primary statement, which is often
the Action Statement. In other words, a sign that says “Keep
Out!” Needs to be sized so that the height of the capital letter
“K” is visible from the necessary distance [see table]. |
|
| This chart is based on the recent
ANSI 535.2 standard for favorable and unfavorable conditions. It is
far more conservative than the “rule-of-thumb” that is
used for traffic signs, which allows 50’ per inch of letter
height for normal reading and 37.5’ per inch of letter height
for minimum reading distance. |
| |
| Capital letter height |
8.00"Min.
Reading distance
(for favourable conditions) |
Min. Reading distance
(for unfavourable conditions) |
Common Sizes
for Signs |
| 0.25” |
6' |
3' |
3.5" x 5" |
0.5"
|
13' |
6' |
3.5" x 5" |
| 0.75" |
19' |
9' |
5” x 7” |
| 1.00" |
25' |
12' |
7” x 10” |
| 1.50" |
38' |
18' |
10” x 14" |
| 2.00" |
50' |
24' |
14” x 20” |
| 2.50" |
63' |
30' |
14” x 20” |
| 3.00" |
75' |
36' |
20” x 28” |
| 4.00" |
100' |
48' |
20” x 28” |
| 5.00" |
125' |
60' |
24" x 36 |
| 6.00" |
150' |
71' |
24" x 36 |
| 7.00" |
175' |
83' |
24" x 48 |
| 8.00" |
200' |
95' |
36" x 60” |
|
