Red cabin lights impair air medical crew performance of color-dependent tasks

Red cabin lighting is often used for nighttime patient transports in helicopters. This study was conducted to determine if red lighting results in impairment of color-dependent tasks.

An emergency medical services pilot adjusted red lighting in a BO-105 cabin to maximum acceptable intensity. Thirteen emergency room residents were shown positive and negative CO2 detectors and skin-colored and cyan-tinted rubber masks; percentages of correctly identified masks and detectors were noted. Subjects also read drug name and amount from 12 medication labels. Wilcoxon analysis (p = 0.05) was used to compare label reading accuracy between two groups: control (black/white lettering/background) and red (red lettering or background).

Percentages of accurately identified masks and detectors in the red light setting were as follows: normal mask 61.5%, cyanotic mask 30.8%, negative and positive CO2 detectors 46.2%. Ability to correctly read medication labeling was significantly (p = 0.003) greater in control (76.9 +/- 10.9%) as compared to red groups (16.3 +/- 13.4%).

Red cabin lighting appears to impair performance of certain critical tasks requiring color discernment. Consideration of this by medical crews working under red light conditions could reduce risk for patient-care errors.