I often see internal quality specifications come with an orange and a red zone - that is to say, with a warning level vs a 'real' quality problem.
While it's well intended - reacting before you've got a real problem on your hands - there is a better way to signal operators when to act on the process and/or the product: I propose using this traffic light system.
It clearly indicates when not to touch the process at all, indicates when the process should be investigated and when it's needed to block products.
#qualitymanagement #continuousimprovement #operationsmanagement