What is Andon in Lean?

What is Andon in Lean?

Andon is a signal used to alert Lean teams of an important status change, an activity that has failed or is running sub-optimally. The Andon can be a light going off, a text display on a ticker board or a sound alert. The important thing is that it is automated, since manually triggered signals are too easy to fail, and that it attracts workers’ attention. Its point is to alert them to stop what they’re doing, and go fix the problem.

Andons in everyday life

We encounter Andons in everyday life, e.g. when an engine warning light flashes on the dashboard, signalling an issue with the car. Ideally, it should force us to drive to the nearest service station to get it resolved. Andons have also been utilized in store or post office queues, and any customer service oriented teams, but we’ll get back to those later.

In tandem with Jidoka

At Toyota, Andon devices tied in with the company’s philosophy of Jidoka: the automation of problem or defect detection. It meant that if anything on the production line went wrong, the line would be stopped and the defect would be resolved right then and there.

Jidoka emphasizes that you fix the problem at its source, hence a well implemented Andon should alert you exactly at the time of a problem occurring, and - if possible - at the exact place where it’s happening. Andons fit in with the principle of visualization, allowing teams to get a clear indicator that something is wrong and needs fixing.

In Western society, we often like to put our best foot forward and sweep any problems under the rug. The latter concept is frowned upon at Toyota. If there are any problems on the Toyota production line, then everyone will be aware of it, and teams will often swarm to sort it out.

Andon must be tied to the Value Stream

Agile software teams are known for heavy use of Andon devices. You can often see red, orange and green indicators on build servers used to compile and test code. If there’s a failure on a server, developers are encouraged to stop what they’re doing and fix that problem first.

But what we’ve seen is that the application of Andon is not as easy as it can appear. In certain cases, teams are being alerted to activities or events that they would not regard as important at all! For example, there might be an Andon that warns of low disk space on a build server, and an orange light flashes - but to a developer concerned about getting their code done on time, this may not seem that important, and they will simply ignore it.

In some supermarkets or banks, there are lights indicating the average queue waiting time, but in most of such cases, you can see that leadership has not trained staff how to resolve the issue - so that the Andon becomes just an indicator of bad service, rather than a light to marshal teams to fix a problem. Unfortunately, most of these implementations have missed the point of Andon completely.

Were these supermarkets using Andon right, then whenever the waiting time estimation lights up as orange or red - more check-outs should be opened to help with the number of customers waiting for service. Their Value Stream is in people getting through checkout and out the door, not in people observing a stagnant queue in front of them.

Andon won’t work in command and control environments

Andon can be a life saver or a bell of foreboding - which it will be for your team depends on the culture that stems from leadership. If management encourages workers to come forward with problems, so that they can be resolved, then Andon will work wonders. But in uncompromising command and control environments, where there’s no room for error or malfunction, we’ve seen teams go as far as to unplug their Andons. When asked why they did this, they explain that the thing just causes management to panic and they get into trouble.

Now, unplugging the Andons does not remove the problems, it only removes a part of the story from management, causing miscommunication, deepening lack of trust and misaligning all performance metrics, which are missing data of errors having been resolved as part of the process.

Use Andon the right way and don’t waste a great opportunity to get to know your process and the team better - both of which are necessary to perfect and continuously improve production.