Samenvatting
This project was instituted to determine minimum and maximum limits of vehicle control label illumination and to recommend procedures for compliance testing. In order to establish a minimum brightness levels, a psychophysical procedure was used to establish the 95% correctness threshold for 95% of older drivers. Results showed that minimum brightness levels must be specified as a function of a letter size and contrast ratio. Older drivers required almost 10 times more light than younger drivers.