Office of Aerospace Medicine Technical Reports
FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute
Report No: DOT/FAA/AM-79/22
Title and Subtitle: Readability of self-illuminated signs in a smoke-obscured environment
Report Date: September 1979
Authors: Rasmussen PG, Garner JD, Blethrow JG, Lowrey DL
Abstract: This study investigates the ability of people with normal distant visual acuity to identify self-illuminated emergency signs in a smoke-obscured environment. The results indicate that signs whose background luminance meets or exceeds the requirements of Federal Aviation Regulation (FAR) 25.812 are readable under favorable conditions when the total optical density of the smoke between the observer and the signs ranges between 3.00 and 3.55. Substantial increases in character sizes in the signs produce only moderate improvement in readability. Some limitations on the practical application of these data to predicting sign visibility in adverse conditions are discussed.
Key Words: Visual performance, Aviation safety, Postcrash fire, Emergency evacuation
No. of Pages: 8
Civil Aerospace Medical Institute
Report No: DOT/FAA/AM-79/22
Title and Subtitle: Readability of self-illuminated signs in a smoke-obscured environment
Report Date: September 1979
Authors: Rasmussen PG, Garner JD, Blethrow JG, Lowrey DL
Abstract: This study investigates the ability of people with normal distant visual acuity to identify self-illuminated emergency signs in a smoke-obscured environment. The results indicate that signs whose background luminance meets or exceeds the requirements of Federal Aviation Regulation (FAR) 25.812 are readable under favorable conditions when the total optical density of the smoke between the observer and the signs ranges between 3.00 and 3.55. Substantial increases in character sizes in the signs produce only moderate improvement in readability. Some limitations on the practical application of these data to predicting sign visibility in adverse conditions are discussed.
Key Words: Visual performance, Aviation safety, Postcrash fire, Emergency evacuation
No. of Pages: 8
Last updated: Friday, June 1, 2012