Effect On The Farnsworth D-15 When Adapting To A Sodium Vapor Lamp.

Background: The sodium vapor lamp has many applications including lighting our roadways, parking lots and warehouses. This type of illumination may cause changes in color discrimination in persons with normal color vision. This study examines a subject's color discrimination pre- and post- adaptation to a sodium vapor lamp to determine whether color discrimination changes over time. Methods: The sodium vapor lamp was calibrated to 28 foot-candles. The color vision of 33 subjects was tested with the Farnsworth D-15. The test was administered immediately after exposure to the sodium vapor lamp and then repeated after ten minutes of exposure to the lamp. Results: The results were analyzed using the Color Vision Recorder and SPSS software. There was not a statistically significant difference in mean scores due to adaptation for the pre and post CCI, AC-CCI, and C-Index found in this experiment. The pairedsamples
T-Test did not reveal a statistically significant difference in mean scores for the S-index from the pre- and post-adaptation tests. Conclusion: Results show that color vision discrimination remains constant under sodium vapor lighting demonstrating agreement with previous studies that report nearly instantaneous chromatic adaptation for color vision discrimination under various lighting sources. The fact that the Farnsworth D-15 does not detect minor defects may be considered a source of limitation in this study. Nevertheless, the resultant data is sufficient to lay experimental designs for further investigation. Other more sensitive color vision tests should be implemented in studies similar in structure.