Relevant standards (e.g. AIAG Handbook, VDA Volume 16) clearly warn of the risks of slippage during human visual inspections. A pure visual inspection is ineffective as a safe shutdown measure, only useful as an immediate measure. A complete exclusion of faulty parts after a visual inspection is impossible for everyone, even the specialized service provider. Reasons for this are e.g. concentration fluctuations, performance pressure, fatigue, environmental influences, health impairments, etc.. The literature speaks of different transfer rates from 3000 ppm up to 30000 ppm for complex testing tasks.
The "zero error principle" represents a limitation to the best possible minimum. The consistent use of many instruments and processes connected in series is the path that the schambeck group is continuously developing in order to come as close as possible to the "zero-defect principle". Nevertheless, the service provider cannot give any guarantee of liability for the exclusion of the passage of defective parts during visual inspections.
- person-related measures
1. aptitude test for hiring (branch-related or partly customer-related)
2. induction and qualification programme SELMA (SchambeckELeraning&wissenMAnagement)
3. random sampling of new employees by Q team leaders
4. MSA capability test on the human test system after a Gauge R&R study (only for part-specific series tests). Analysis of whether the employee is able to find defects within the specifications with repeat accuracy.
5 "Eye test equipment" - exercises for relaxation and recovery of the eyes, especially during tiring "visual inspections" such as the detection of color deviations or rigidly focused viewing angles.
6. visual tests and regular examinations according to G25 and G37
- process-related / organizational measures
7. 20-point checklist for setting up a Q-gate, with all specifications that must be available in order to set up an effective Q-gate
8. internal audits & audit plan
9. 8D process in case of complaint to avoid repeat defects
10th ERFA (exchange of experience in shift book, daily team meetings, monthly NL-meeting Team-to-Team and 3x a year exchange of experience in management circle between all NL)
11. job rotation for monotonous inspection tasks
Christian Schambeck, 17 July 2019