Examples of poor design from an engineering expert witness and consultant

Abstract

As an engineering expert witness and consultant, the author has participated successfully in about twenty six cases that involved personal injuries or death. Seven of the above cases are briefly outlined to illustrate how inadequate design and/or analysis of components, parts, subsystems and products resulted in death of users or severe injuries to users. One example is a liquid sprayer that was designed incorrectly, without regard to applicable standards. In addition, neither design failure mode and effects analysis (FMEA) nor process FMEA was conducted. This product resulted in the death of one user. This paper will discuss this case and summarize what designers can and must learn from it. The rest of the six cases will be presented briefly to illustrate what designers can learn from each case. The focus will be on design principles, instructions to users, applications of human factors in design, and designing for safety of users.