This study assessed perceptions of hazard levels associated with three signal words, CAUTION, WARNING, and DANGER, combined with four background colours, white, yellow, orange, and red. In general, DANGER was perceived as indicating the highest level of hazard, WARNING, an intermediate level, and CAUTION, the lowest level. Greatest consistency was found for DANGER. There was a small but significant amount of disagreement about the relative amounts of hazard represented by CAUTION and WARNING. White, yellow, orange, and red were also perceived as being associated with successively greater levels of hazard. Greatest consistency was found for DANGER with a red background. There was little agreement about the best colours to be associated with CAUTION and WARNING. Ratings on scales of seriousness of injury and probability of injury show that people perceive CAUTION and WARNING to be much closer to each other than to DANGER.
A. Chapanis (Tue,) studied this question.