ANDON: Visual Control

Most of the information people collect comes from signs and signs. We live daily with multiple signals around us and consciously, or not, we use them to increase our understanding of our environment, facilitating constant decision-making with a high degree of independence.

What is Andon?

Andon is an expression of Japanese origin that means “lamp” and relates to visual control. In turn, it is considered as an element of the Lean Manufacturing philosophy, which brings together a set of practical communication measures used for the purpose of obviously and simply capturing the state of some productive system.

The above is a definition, so to speak, general. In reality visual control as a communication technique has multiple applications, perhaps the most important are related to the identification of anomalies and waste; and its main purposes are to facilitate both decision-making and staff participation, providing information about how their performance influences results, thus ensuring that you can have greater control over your goals. It can then be said that visual control empowers and motivates staff through information.

It is very important to emphasize that visual control is a tool that should support the measurement of processes, not people. So if the measurement allows to identify the performance of individuals, attitudes towards responsibilities, not personal consequences, should be generated.

When should Visual Control be implemented?

As a communication tool, visual control should focus on information that represents added value in a process. So it is usual for its implementation to always be welcome, and is an ideal complement to methodologies such as 5’s, waste disposal, SMED and many others. It is advisable to prioritize those processes in which we identify opportunities for improvement through signage, as an indicator of actions and decision-making.

Its implementation can be carried out, among many others, in the areas of:

  • Process or manufacture.
  • Storage.
  • Equipment.
  • Quality assurance.
  • Maintenance.
  • Security.
  • Organizational management.
  • Offices.

It is worth noting that the implementation of visual control must follow a systematic process, for which it is important to consider, among others, the following issues:

  • Does the process we want to control add value?
  • What indicators do we want to monitor?
  • According to the calculation of the indicator, where should it be monitored?
  • How are nonconformities or anomalous situations identified?
  • Who or how is the information recorded?
  • How can indicators be reviewed?
  • What action should be taken according to the indicator information?
  • What decisions should be made according to the indicator information?

What are the benefits of visual control?

The main benefit of visual control lies in improving the flow of relevant information, and standardizing communication. In addition, implementing Andon or visual control can contribute to:

  • Remove waste or move.
  • Improve quality.
  • Improve response time.
  • Improve security.
  • Standardize procedures.
  • Improve work planning.
  • Contribute to order and organization.
  • Stimulate participation.
  • Motivate the staff.
  • Reduce costs.

Types of visual control (Andon)

As mentioned above, visual control has multiple application methods, these fit different objectives and can be broadly classified into:

  • Visual control of equipment and spaces.
  • Visual control of production.
  • Visual control at the workplace.
  • Visual quality control.
  • Visual security control.
  • Indicator management. 

Below are some of the most commonly used visual control practices.


Alarms are a basic type of audio-visual control, usually used to communicate urgent situations. It is normal for organizations to be assigned different warning relationships according to the number or type of sounds. For example:

  • 1 Sound: Security situation involving alert to the company’s security department.
  • 2 Sounds: Security situation involving alert and call to the entire security brigade of the company. The rest of the collaborators should remain vigilant, but they can continue their work.
  • 3 Sounds: Serious security situation involving alert and call for the entire company security brigade. The rest of the collaborators should evacuate calmly and go to the established shelter sites.

In addition, it is common for alarms to be tested once a week, on the same day and at the same time.


Colored lamps, also known as turrets, are installed on production lines, equipment or manufacturing cells; for the purpose of communicating the status of them. They are usually used in very numerous lines and eventually replaced by colored flags. Each color represents a state, and the relationship state- colors varies from company to company, however it is common to find that:

  • White / Blue: Problems related to the raw material (e.g. supply).
  • Green: Equipment or cell operating normally.
  • Yellow: Equipment or cell inactive due to some maintenance failure. If the light is flashing it may represent a reference change.
  • Red: Equipment or cell with quality problems, or in which an accident occurs.
Andon - Turrets
Machine-indicator light turret

Installing these elements involves establishing an action protocol, so that the state representing the turret seeks to attract the attention of a person responsible for: sourcing, maintenance, security, production, or a supervisor.


A One Point Lesson, also known as LUP, is a communication tool, used for the transfer of simple or brief knowledge and skills. It is worth clarifying that although the knowledge transmitted through a LUP is inconscient and unproficient, it must be reviewed and approved, and does not replace a Standard Operating Plan (POE), in fact it can be used as a complement to an SOP, or to transmit information that does not require it. A good LUP should essentially allow for easy, clear and accurate learning.

For example, it is normal for the handling of printing or photocopying equipment to be carried out by a person, and that some workers do not know about the operation of the equipment; so a LUP detailing the operation steps of the computer can be very useful at any given time.

Even lessons from a point can complement different methods of visual control, so for example, a contributor can create a LUP in which he specifies the meaning of the colors of the “turrets” installed on the production lines, or the meaning of the “safety pyramid”.


Information boards are visual control tools used to give automatic and continuous traceability or tracking to the production plan. In practice the board is usually programmed with a counter whose rhythm is based on the takt time (customer purchase rate). 

It is also scheduled with another counter that is updated with the records of finished units sent directly from the line. So the takt counter can be considered as the goal, and the difference in actual process productivity can be evident.

“Productivity means doing things in such a way that, in the case of the company, it is as close as possible to its goal. Anything that brings a company closer to its goal is productive; anything that does not carry it is unproductive.” The Goal (Eliyahu Goldratt).

Control Boards -


Checklists or checklists are visual control tools that allow activities to be carried out in accordance with a previously established procedure. These lists have a myriad of applications, and are often used to follow safety and maintenance procedures to the foot.


One of the main visual control tools to implement order, organization and standardization are marks on the ground. These brands are usually made by means of vinyl tapes for the purpose of identifying point workstations, product, raw material, to identify transit areas, caution and safe areas. It is common to find that the color ratio is done as follows:

  • Green area: Indicates good product.
  • Blue area: Indicates raw material and product in process.
  • Red area: Indicates non-compliant product.
  • Yellow/white marking: Delimits corridors, safe transit areas.
  • Black and white marking: Delimits maintenance areas.
  • Black and yellow marking: Delimits precautionary areas.
  • Red and white marking: Delimits safety areas.
Plant Signaling -

They are certainly an essential visual control tool, which denotes organization and prevents chaos.


Like floor marking, job marking is an important tool for implementing order, organization, and standardization. They certainly contribute to the improvement of workstation efficiency.

Job Marking -


Result dashboards, also called performance dashboards, are a visual control tool used for the inclusion of performance indicators. Its main function is to demonstrate how the performance of collaborators influences the results of processes, lines and organizational objectives. These tools are very rich in relevant information and added value, according to this, a collaborator after analyzing a results board will have a broad idea of the state of the processes, therefore contributes, among other things, to line changes, to the speed of response, to plant presentations, to the motivation of the staff, etc.


The safety pyramid is a visual control tool used to represent the indicators set in Bird’s causation theory. It shows us the proportionality between accidents with loss of working days, accidents without loss of working days, accidents with material damage and incidents. In addition, it can be supplemented with safe days indicators and safe practices.

Safety Pyramid -

As has been evident, there can be as many methods of visual control as possible; the important thing is that there is a high degree of commitment of the management of the organization in the implementation of the control tools, this depends on the interest that collaborators give to these methodologies.

Similarly, it is important to consider that training staff in understanding visual control tools is an essential step.

ANDON: Visual Control
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