Visual Signals

Demarcation ZonesGenerally in Lean, the intention is to make the current situation as clear as possible to everyone who needs to know it.  I have made two previous posts about a visit to the Nissan UK plant in Sunderland (posts on Level Scheduling and the Drum-Buffer-Rope system). There are a whole variety of visual methods used in Lean, and many of them were in use at Nissan.

Process Control Boards

There are various names for Boards that show the current status of a process, but ‘Process Control Board’ is as good a name as any. There were several types of these on display at Nissan. Some Boards showed the current production status compared to the projected number at that time of the shift. Others told the operator the details of the car on which they were working, and told them what type of car was arriving next (this was a mixed production line – please see this post for more details).

Demarcation Lines

Demarcation lines communicate information about the use of an area. There were several types in use at Nissan:

  • Lines showing safe and unsafe areas. Wide blue areas on the floor showed where it was generally safe to walk – although caution was always required. These turned in to striped blue areas where they crossed an internal road, showing where careful attention is required, for example because of automated vehicles. Where there was no pedestrian access, there were wide red floor areas. .
  • Tiger stripes were used in some areas, such as an area at the edge of a walking route, where an automated vehicle swung round, and came close to the pedestrian walkway.
  • Areas showing the location of equipment. When items were in areas not normally used, there was signage on the equipment that not only asked staff not to move it, but explained what it was, why it was there, and who to contact if there were any queries. An example was along the lines of ‘Maintenance equipment required for 2015 shutdown. Please do not move. Contact __________ with any queries’.  Explaining to people why they should do something strikes me as preferable to blanket instructions with no explanation.

Standard Work

In several locations, I saw photographs showing how something was to be arranged, as part of 5S, and photographs demonstrating techniques. I assume these were recent changes to a process. Standard work included information relevant to error proofing: I plan to cover this in more detail in a future post.


One type of kanban is a card that attached to supplies, and which is used to control re-ordering and re-supply of necessary stock. I haven’t been to a Toyota plant, but I suspect they may use these more than was evident in Nissan. Small items are controlled by kanbans, however, at last for re-stocking of pick up points where staff could take small items that they needed in their work. A contractor then re-filled the stock bins, using kanbans.

Skills Matrices

Skills matrices are commonly used when multi-process working is required. It is important to have enough people skilled in necessary tasks – Nissan used the mantra ‘one person, three tasks’, indicating that everyone on their production line needed to be able to do at least three tasks. In practice, the skills matrices on display in each zone made it clear that many staff could do far more than three tasks.

Links between Strategy and Delivery

Areas in each production zone, and along side production lines, made clear the links between company strategy, plant requirements, and the work of each of the production lines and zones.

Problems and Improvements

The zone rest areas, where team briefings are also conducted before each shift, included sheets showing quality and safety concerns raised by team members, and the response to them. Other areas showed current improvement projects being undertaken, and changes made from them.

Application to health and social care

It’s difficult to think of any of these that do not have an application in some health and social care settings. On a brief visit, it is difficult to judge use, but the observation that jumped out was that the scale and apparent consistency of use far exceeded anything I have seen in a UK health care setting. Hospitals are dangerous places, but not generally as dangerous as manufacturing facilities – the use of demarcation lines for example will be higher in industrial settings. I am impressed, however, with the clarity of message. I knew very little about Nissan, and my knowledge of car manufacturing is non-existent, but I understood the gist of most of what I saw. If we can design, and consistently use, signage that conveys meaning as well as Nissan have managed it, we will be doing well.

One thought on “Visual Signals

  1. Pingback: Lean and Person-Centred Care |

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s