Work content (Wc) represents total operator cycle time or, if multiple operators, the sum of operator cycle times to perform a specific process(es) or sub-process(es). The scope of human work, including both value-added and non value–added activities, may encompass a complete value stream or only a portion of it. For example, the lean practitioner may speak of the work content to check-in and room a patient, assemble a sensor module or process a claim. The term “total work content,” is applied when referencing the work content to build a product in its entirety, completely execute a certain transaction, etc.
As the name implies, the focus is on the work; reflecting the sum total work of ALL people within the subject process(es) or sub-process(es) to complete one cycle. Think about work content as the work, comprised of manual, wait, and walk time, it would take if one person were to execute the entire cycle all by himself. Of course, when one person does do the entire cycle, work content is pretty easy to determine.
Wait time excludes inter-operator waiting. For example, the lean practitioner would not include the time of operator B waiting for operator A to present a sub-assembly within the work content calculation.
It is important to understand total work content for the purpose of determining optimal staffing levels and to understand work content variation and its implications within a mixed model environment.
The math follows: