A few weeks ago I was in Sam’s Club headed for checkout. For those not familiar with Sam’s, the typical checkout consists of a series of cash register islands with a lane on either side. The registers are grouped in pairs. Rather than being side by side, one is in back of the other as you approach.
As I approached, I noticed that one had a closed (cerrado) sign but I could not tell which lane was closed and which was open.
The front register, serving the left lane was closed. The rear register, serving the right lane, was open. The problem was that the open/closed signs are on the opposite sides from the checkout lanes that they serve.
Look at the picture. It appears that the left lane is open and the right closed when it is actually just the opposite.
It took me a moment to figure out which lane was open.
So what about in your plant? Is your signage clear and unambiguous? Can everyone, especially those unfamiliar with the sign, instantly know what it means? Or do they have to pause and think about it? Based on my experience in many different plants as well as general life experience such as above, my bet would be that you have some combination of ambiguous and unambiguous.
I will also bet that, if it is a sign you see every day, you may not even realize that it ambiguous.
Our lives revolve around visual cues. In addition to signs, we need to fill out documents, operate equipment and more. If the visual cues involved in these tasks are not clear, we will at best be slowed down trying to understand what they mean.
Have you ever started filling out a form where it said, for example, “Name” but it was unclear whether you were to fill in above or below? I run across this routinely and don’t realize it until I have the whole form filled out wrong.
At worst, we will not follow the signals correctly. In extreme cases we may do the opposite of what we are supposed to and cause a safety incident. There is a reason why “Emergency Stop” buttons must be red on a yellow background and cannot be used for any other purpose. (Such as giving to a Russian under the guise of a “reset” button.)
We need to always keep a critical eye out and eliminate these ambiguities and strive to eliminate them. As I said, they are not always hard to see once we get used to them. One technique I have found useful is to take someone who is seeing it for the first time and ask for their reaction. Do they understand it correctly? Equally important, do they understand it correctly immediately or do they need to stop and figure it out? If the latter, you have some work to do. Ask them why it was not obvious. Incorporate their comments in the redesign. It may take several iterations to get it right, but it is important.
One excellent book on the use of visual cues is The Design of Everyday Things by Donald Norman. This looks at some common things we take for granted and how they could be designed better. One of his pet peeves is the common kitchen stove. Burners are arranged in a square. Controls are often in a line and it is not always obvious which knob controls which burner.
Another excellent book is The Visual Factory by Michel Greif. This covers different ground in that it is specifically the use of visual cues on the factory floor. In addition to discussing how to drive out ambiguity this book also addresses the need to make all information as visual as possible.
Both are available at Amazon, B&N and elsewhere.
