Effect of Text Format on Determining Tires’ Date of Manufacture

Abstract

Previous research indicates that most consumers are unaware that older tires can deteriorate and lead to tread separation which could result in crashes. Even if they were to know about this hazard, the task of determining the date of manufacture (DOM) on tires is difficult. In the U.S., consumers must decode a 4 digit number at the end of a longer U.S. Department of Transportation (DOT) identification number in small, black print embossed onto black sidewalls. Eighty-three participants (45 students and 38 adult non-students) were asked to decode 6 different date of manufacture (DOM) markings. Analyses showed that people have difficulty with determining dates in the current U.S. DOT format and that date formats resembling common U.S. date representations were more understandable to participants. Additionally, only half of the participants reported having knowledge of tire aging issues and few have looked at the DOT identification number before participating in this research. Discussed are implications for date formatting, followed by guidance on designing a more consumer-friendly DOM.