Various types of visual controls in production processes.

1Based on fecal and urine pattern in the dirty bedding of a mouse cage, the term biological kanban was originally coined by Khan and Umrysh (2008) [23]. The data presented in Results section V (Figure 5B) strengthens this term by relating ammonia levels to fecal/urine patterns – thus signaling to staff that it is time to change the cage.2For a more detailed discussion of pitch, and how it relates to takt time, the reader is referred to Creating a Lean Culture by David Mann [42].