We work together with the management and the head production engineers in several Bangladeshi garment factories to implement the intervention. Participation in the project is still advertised, therefore the exact number of factories in the project is not yet determined. The intervention is of the following nature: Whenever a sewing line in the factory starts producing a new garment that it had not produced before but that was already produced on another sewing line, than the supervisor of the line that already produced the garment is actively involved in setting up the new line for producing the same garment. Sewing lines in our Bangladeshi partner factories typically switch the garment they produce every 1-3 weeks, and it is very common to see garments being produced on more than one line, while usually starting on different days. Switching the garment typically requires both changes of the machines used and/or adjustments on the machines themselves, such as change of the needle type or yarn type. The workers on the lines also need to be explained the new operations they have to perform on the new garment. This process of the style change can take between 1 hour and 1 day (but is usually done in the `zero-feeding' process, that is, in the line, one machine after another machines is adjusted, and the machines not yet adjusted still produce for the old garment while those already adjusted already work on the new garment. Thus, on average, each machine is idle only 15-30 minutes).
In the randomly selected lines, whenever they switch to a garment that has already been produced on another line in the factory, the line supervisor from the earlier line should be actively involved in the described change process. He should brief the new line supervisor on the most important things he has learned while producing the garment on his line, and inspect the line changing process, either after the end of the line changing process or while the most important machines for the production of the new garment are set up.
To monitor the intervention, we left with the factories either a tablet or a book, in which they should fill out a short survey every time a style change on a treatment line was "treated". The survey asks about the line that starts the garment and the line that already produced it, involved line supervisors, the garment itself, and a few questions on how well the communication went as perceived by the superiors of the line supervisors that instructed the briefing. The tablets send each report directly to a server upon finishing, while the books are collected regularly. Thus, the extent of the implementation, and whether it was implemented in the correct lines, can be checked throughout the experiment is running.