Reduce the number of incorrect codes

A food manufacturer had significant failure costs due to non-readable coding. After a cause analysis, they found that the printer head was not cleaned properly and this led to anomalies. The reason the operators did not clean the printer head properly was that they did not have a clear standard and training for this task.


Each month, €35K of failure costs were written off due to unreadable codes. The unreadable codes were created by a poorly cleaned printer head. This anomaly was caused by employees not knowing exactly what, how and why they could clean a printer head in the best way possible.

In this case, Job Instruction was required, as there was no standard for performing this operation. In addition to the lack of the standard, instructions were given according to the traditional way of training: walk along, just tell or just show. After the cause analysis, a One Point Lesson was set up, but again no significant improvement was achieved as the way of instructing did not yield the desired result.


After the cause analysis it was established that the standard working method was lacking and that the way of training could be improved.

- A pilot was started, which stated who would become a TWI Job Instructor, which tasks should be standardized and which people needed training.

- During the training week, the task was analyzed and the standard how to clean the printer head was recorded in a Job Breakdown.

- When setting the standard, the specialists found out that they needed additional cleaning agents. These were purchased immediately after approval of the supervisor.

- A plan was drawn up to train who should be trained to clean the printer head, and when.

- During the execution of the training plan, the supervisors, in this case team leaders, checked on the shop floor whether the task was carried out according to the standard.


The costs of failure have been reduced to 0 according to the execution of the training plan.

After this success, an analysis was made of other quality deviations caused by the actions of people. Also for these tasks standards have been drawn up and these have been trained to the employees according to the 4-step method of Job Instruction.