CLASSIFICATION AND FACTORS OF HUMAN ERROR IN THE CREATION OF MANUFACTURING DRAWINGS AND MATERIALS LISTS.

Abstract

In any process, there is always the possibility of errors during its development. The task analyzed in this case is one of the tasks of the tool design process for the soldering of components on electronic boards, which consists of generating drawings and bills of materials of the designs made. In this activity, cases are frequently reported where errors such as erroneous or incomplete information cause delays, bottlenecks, rework, and waste that represent costs and inefficiency. The objective of this work is to use techniques to analyze human reliability and propose concrete recommendations to reduce the possibility of human errors. The study was carried out with cognitive ergonomics tools such as Hierarchical Task Analysis (HTA) and then with the Systematic Human Error Reduction and Prediction Approach (SHERPA) method. A convenience sample of eight design team members was used in a tooling manufacturing company for electronic board component soldering processes in Ciudad Juarez, Chihuahua, Mexico. The HTA was broken down into the main task and subtasks that integrate it, obtaining detailed information of the activity of each one of them, proceeding later with the classification and association of error modes in each one using the SHERPA method, determining the consequences associated with each error mode. Task 4 generating drawings and designing BOMs, turned out to be the most extensive task in the process with 17 subtasks and these subtasks with activities that demand high levels of attention, are repetitive, and are executed with urgency so it is vulnerable to errors. By classifying and associating the error modes of each subtask with the SHERPA taxonomies, the consequences, possibilities, and criticality of these error modes were identified. A total of 26 human errors, of which 25 were action errors (96.15%) and 1 selection error (3.84%). The taxonomies identified with the highest presence were “omitted activity” with 13, followed by “incomplete activity” with 9, “activity too short or long” with 1, “too few or too many activities” with 1, and “incorrect selection” 1. The criticality and probability, together define a level of risk of occurrence of the error, the level found in the subtasks analyzed was high in 18 of them (69.23%) and medium in 8 of them (30.77%). The repeatability of the activities in each project, taking into account that 2 to 3 are performed daily by the designer, makes it an extensive task and vulnerable to errors due to conditions, so it is advisable to make changes to this activity.