Kent P. Vaubel

The New Alcohol Warning Labels: How Noticeable are They?

An experiment was conducted to assess the effect of various existing warning design factors on the noticeability of warnings on alcoholic beverage containers. One-hundred containers, 50 with warnings and 50 without, were used as stimuli and the time required to determine whether or not a warning was present was recorded. The results indicate that warnings on the front label were found more quickly than warnings appearing in any other location. Also, warnings printed horizontally were found more quickly than warning printed vertically. A regression analysis found that features of the signal word/phrase (“Government Warning”), as well as the amount of “noise” or clutter on the surrounding label, significantly influenced warning detection times. Thus, some of the design features currently used were shown to have an effect on noticeability of warning information. It is suggested that proper manipulation of these features could make the mandated warning more noticeable.

Effects of Explicitness in Conveying Severity Information in Product Warnings

Manufacturers typically provide consumers with a warning message on the label of potentially hazardous products in order to encourage their safe use. Warnings often vary in explicitness and severity, where explicitness refers to the specificity of the stated injury consequences and severity refers to the harshness of the consequences. This study examined the nature of the relationship between explicitness and severity and explored changes in peoples perceptions of four common consumer products as a result of exposure to warnings that varied on these two dimensions. The results show that explicitness and severity are related. The results also demonstrated that exposure to explicit warnings produced an increase in rated severity of injury and intent to act cautiously with a product. Overall this study suggests that, unless they are explicit, warnings on common consumer products may not change perceptions and subsequent intentions to act cautiously.

Inferring user expertise for adaptive interfaces

A technique based on two heuristic rules for inferring expertise is demonstrated by inferring user expertise in word-processing tasks. The heuristic rules were translated into practice by examining command frequencies and requests for on-line help from the 12 participants in the study who were engaged in personal word-processing tasks. These variables were found to be related to word-processing expertise. A scoring rule derived from these variables ranged from 71% to 87% correct in predicting the expertise of the user. The application of this technique to adaptive interfaces that incorporate estimates of user expertise is discussed.

Validity of Isometric Strength Tests for Predicting the Capacity to Crack, Open, and Close Industrial Valves

Cracking, opening, and closing valves are physically demanding tasks required of chemical plant process operators. This study determined if isometric strength tests predicted the capacity to: 1) crack valves; and 2) fully open or close them. The study involved three interrelated steps: 1) compete task analyses to define the torque required to crack valves and the total amount of work required to open or close industrial valves; 2) develop valve turning simulation tests; and 3) complete laboratory studies to define the level of isometric strength demanded for valve turning performance. A total of 405 valves at two major chemical plants were measured to find the torque required to crack, open, and close industrial valves. These data were used to develop two job simulation tests, one measured valve cracking capacity, and the second the endurance needed to open or close a valve. An electronic torque wrench measured valve cracking capacity in eight different ways, and a valve turning ergometer measured the subjects endurance to work for 15 minutes at a power output of 1,413.5 foot-pounds/minute. The sum of isometric grip, arm lift, and torso lift strength tests (ɛIS) measured strength. The isometric strength and endurance work valve tests were administered to 26 men and 25 women. The isometric strength and valve cracking tests were administered to a second sample of 118 men and 66 women. The correlations between ɛIS and work test performance were 0.65 and 0.83 for valve cracking and valve endurance tests respectively. Logistic regression models defined the strength level needed to crack valves and completely close valves.

Effects of Warning Explicitness on Consumer Product Purchase Intentions

Two studies examined the relationship between the explicitness of hazard consequences described by a warning label and purchase intentions. Subjects indicated buying preferences for consumer products displaying explicit and nonexplicit warning labels. A total of 6 common consumer products was used in Experiment 1. Subjects were shown a questionnaire containing information about products varying in price, quality and warning label explicitness. Sixty-six subjects rated 2 products and ranked 2 products based on which they would be most likely to purchase. Results of the rating and ranking tasks suggest that products containing nonexplicit warnings were significantly more likely to be purchased. In Experiment 2, both explicit and nonexplicit warning labels were simultaneously presented for each of nine products and subjects rated with which warning they would prefer to buy the product. Results of Experiment 2 indicate one product was rated significantly more likely to be purchased with an explicit warning label; whereas, two products were rated more likely to be bought with nonexplicit warnings. There were no significant differences for the remaining six products. Overall, nonexplicit warnings were preferred to explicit warnings. However, this trend was reversed for one product, and for many products the detail with which a warning describes potential consequences had little effect on anticipated purchase decisions.

Major and minor injuries at work: Are the circumstances similar or different?

A database containing accident records from a large petrochemical refining complex was employed to test the hypothesis that similar circumstances are associated with incidents that result in major and minor injuries. Results indicated a great deal of similarity for both major and minor accidents and across jobs. Several dimensions or characteristics of the accidents were examined including the kinds of activities employees were engaged in prior to the accident, the sequence of events preceding the injury, the nature of the injury sustained and the parts of the body that were injured. In addition to providing support for the notion that the conditions giving rise to major- and minor-injury accidents are similar, these findings extend previous work by demonstrating that such similarities hold across jobs.

Product Evaluations and Injury Assessments as Related to Preferences for Explicitness in Warnings

Increasing concern about the impact on-product safety information has on sales of a product has focussed attention on consumer decision making as a new area within which to carry out warnings research. Examples of this new research domain include efforts aimed at exploring the relationships between anticipated purchase decisions and the level of detail with which a warning describes consequences of using a product. The level of detail with which consequences are described in a warning is referred to as the explicitness of the warning. In the research reported here, an attempt was made to examine purchase preferences for explicit warnings in the context of cost-benefit tradeoffs made among fictitious products varying in societal value and potential harm. Seventy-three subjects were presented with brief written descriptions of seven products, each having associated with it a unique injury. Explicit and nonexplicit warnings accompanied each product description. Using a questionnaire, subjects evaluated each product in terms of its value to society and indicated whether it should be made available for sale in the United States. They then assessed the severity of the injury and the degree to which they felt it could be controlled by taking the proper precautions. Finally, subjects indicated which warning (explicit or nonexplicit) they would prefer on the product they were to buy. Overall, it was found that products having more detailed, or explicit, consequence information were overwhelmingly preferred. Other patterns indicated that greater purchase preferences for explicit warnings existed when products were considered high in societal value, ought to be sold in the U.S., and when injuries were construed as being controllable. These findings suggest that explicit warnings do influence anticipated purchases of products about which there exists uncertainty concerning product-related danger. This influence appears to be contingent upon perceptions about the costs and benefits associated with the product.

Tire-Rim Mismatch Explosions: Human Factors Analyses of Case Studies Data

Data from 13 accidents involving mismatches of 16 inch tires and 16.5 inch rims were analyzed. These mismatches resulted in tire bead failures during inflation that caused the assembly to explode leading to serious injuries and deaths. The data indicated a number of consistent findings. In ten of the accidents an “entrapment” situation existed in which the person inflating the tire and subsequently injured was not the person who selected the components and placed the tire on the rim. While there was great variance in training, experience and knowledge of tire busters, virtually all were unaware of this mismatch hazard. Tire busters typically did not look for size information on rims, and such information was either not displayed or displayed poorly. Regarding task feedback, because the outer flange diameter of the 16 inch and 16.5 inch rims are virtually the same, placing the tire on the 16.5 inch rim did not provide feedback that something was wrong due to greater task difficulty. Also, the fact that the tire did not properly seat was not attributed to a size mismatch but rather to other more common seating problems. Efforts to warn about the mismatch hazard on the products have not met warnings design criteria and generally have not been effective.