# Statistical Tolerance Analysis--A Survey on Awareness, Use and Need in German Industry
## 3 Surveys on Tolerance Engineering  
The following section discusses surveys in the context of tolerance engineering. Similar to our survey, this section focuses on German industry. Nevertheless, an identical picture can also be seen from a global point of view in recent works [44; 45]. In 1985, [PERSON] interviewed 125 German companies in [46] on the application of updated standards on tolerances and fits. Most of the interviewed companies were in the fields of mechanical engineering and electrical engineering. Nearly all the companies surveyed (92.2%) gave their opinion on carrying out tolerance engineering. The main reasons given for the introduction of tolerance engineering were functional and quality-specific aspects, where cooperation with other companies was also mentioned. However, more than half of the companies (63.6%) still had problems with the implementation of effective tolerance engineering, mainly due to gaps in knowledge and insufficient experience. These implementation problems were particularly evident during the measurement of deviations that appear. About 75% of the companies reported that they did not check shape and position tolerances. In 1995, [PERSON] interviewed 31 companies in Germany [47]. It turned out that shape and positional tolerances were stated to be extremely important for product quality assurance and clear and comprehensive communication with partners. At the same time, the respondents pointed out that gaps in employee knowledge, and comprehension problems during testing led to problems. According to the respondents, these problems should be improved by internal discussions of component drawings and various training of the engineers and departments involved. [PERSON] investigates in [48] the use of tools in tolerancing in the medical device industry, and companies from the aviation industry were also included in the survey. An online survey, which followed several telephone interviews, found that statistical tolerance analyses were rarely applied among engineering design departments in the medical sector. The main reason was seen as the high complexity of the analysis tools. However, companies that used tolerance analysis reported very positive benefits. The extent to which the results of the survey are representative is questionable, since only 13 participants took part in it. Nevertheless, the survey supports the already quoted strictly limited application of tolerance analysis in German industry. The focus of [35] was on the application of tolerance analysis in the field of medical engineering. They discuss the use and challenges of using software tools for tolerance analysis (computer-aided tolerancing, or CAT) in a company. Different employees within this company were interviewed and stated that tolerance analysis was considered highly important and was already applied during product development. However, there was no continuous workflow. Based on these findings, the employees were asked about their requirements of these software, so that their continuous application could be facilitated. The most important finding was the need to improve the link between the 3D-CAD- and the CAT-environments. The authors shed light on the requirements of a company in detail. The general validity of these results, however, is not discussed in the work. The latest survey on the state of tolerance engineering in Germany was carried out in 2018 by [PERSON] et al. [49]. However, the authors have published only a few results since then. The survey focused on the barriers to a proper application of ISO GPS standards in German industry. The authors revealed that \(\sim\)69% (=24 of 35) of the participants were familiar with the ISO GPS standards, but only \(\sim\)67% of them (=16 of 24) were applying ISO GPS. The participants that did not apply ISO GPS in their companies saw the barriers in the \"lack of know-how and expertise\", the \"implementation of the GPS-system in the company's individual product life cycle\", the \"lack of time\" and \"difficulties in communication\".