Perceived Effectiveness of Environmental Warnings

Abstract

This study examined perceived effectiveness of warning signs for various hazard situations. Four-statement signs contained a signal word, a hazard statement, a consequence statement, and an instruction statement. Four additional three-statement signs, each with a different statement systematically removed from the four-statement sign, were used, for a total of 5 signs for each hazard situation. The results of Experiments 1 and 2 indicated that removing content statements reduced perceived effectiveness. Hazard and instruction statements were the most important statements, showing the greatest decrease in effectiveness when deleted. Signs for the most hazardous situations were perceived as the most effective warnings. Experiment 3 examined redundancy of statements in a sign. The results suggested that the deletion of redundant statements, particularly signal words, had less influence on effectiveness. The hazard statement showed the lowest redundancy consistant with it producing the greatest effectiveness decrement when deleted.