- Author
- Collins, B. L. | Goodin, P. J.
- Title
- Visibility of Exit Directional Indicators.
- Coporate
- National Institute of Standards and Technology, Gaithersburg
- Sponsor
- National Electrical Manufacturers Assoc., Washington, DC
- Report
- NISTIR 4532, March 1991, 43 p.
- Distribution
- Available from National Technical Information Service
- Keywords
- exit signs | arrows | chevrons | color | contrast | directional indicators | exit | egress | emergency lighting | sign | visibility
- Abstract
- A three-phase experiment assessed the effectiveness of different configurations for exit signs and directional indicators. Two phases involved visibility assessments, while a third phase was a behavioral assessment. In the experiment, sign effectiveness was determined in terms of distance to detection, correct identification, and rated effectiveness, as well as speed through a corridor. The results indicated that a chevron in grey on white with a contrast of about 0.4 to 0.5 (to meet minimum specifications) was identified correctly at the greatest mean distance and receives the highest mean ratings of effectiveness, as compared to other directional indicators. The combination of a 2.25-in chevron with a 6-in EXIT sign was identified correctly at a mean distance of about 100 ft. Use of color, either red or green, increased this distance by about 15 to 20 ft. Reducing width to height ratio reduced identification distance by about 35-40 ft for chevrons of comparable height, although chevrons of 2.6 to 3.75-in. in height, with a width to height ratio of 0.29 to 0.43, were identified correctly at about 100 ft. These data suggest that chevron width could be reduced if height were increased above 2.6-in, and still maintain adequate visibility at 100 ft. However, visibility is best predicted by total chevron area, with chevrons with larger total areas seen at greater distances. Analysis of the movement data from the behavioral phase indicated that chevrons of 2.25-in provided adequate visibility at about 100 ft but that speed of movement is not a sensitivie indicator for sign visibility. Finally, the data from all three phases indicate the importance of chevron size and configuration as well as sign color and contrast in determining visibility.