On the prioritization of safety warnings in product manuals

Most warning research has focused on how to best present individual hazards on signs and labels. However, many products have multiple hazards and to date there has been very little research on how to effectively present multi-hazard warnings. The present paper studies the sequencing of safety warnings in product manuals using warning statements from manuals of three power tools, each having multiple hazards associated with their use, maintenance, and storage. This research also examines the relationship between statement orderings and several user-belief dimensions. One group of 25 participants ordered sets of warning statements based on how they believed the warnings should be listed in the manuals. Another group of 25 participants rated each warning statement on importance, injury severity, injury likelihood, and prior awareness. The results provide a quantitative summary of preferred statement order that could be useful in assembling warning lists in manuals. Three of the four belief dimensions had substantial negative correlations with mean rank; the fourth, prior awareness, showed a weaker relationship. Empirical assessment of warning statements might be useful in prioritizing multiple warnings in product manuals to better transmit product-related hazards to users. Relevance to industry The present study demonstrates a procedure that could be useful to product and equipment manufacturers on how to prioritize lengthy lists of warning hazards. Empirical determination of the sequencing of safety messages may increase the likelihood that important information will be read and decrease the likelihood of product liability suits that allege inadequate hazard warnings.