For decades, the Andon system meant one thing: a light that turns on. Red—problem. Yellow—caution. Green—all clear. A simple signaling system that became the foundation of Toyota’s production system and Lean Manufacturing worldwide.
Today, as manufacturing plants invest in digitalization, dashboards, and Industry 4.0 systems, the question arises of how to harness the full potential of the Andon system in production—and it turns out that the most difficult part of this challenge has remained unchanged for half a century. It’s not about the technology, but about what happens after the light comes on.
A problem that technology alone cannot solve
In most facilities, the Andon system is technically implemented correctly. The light comes on, the notification is received, and the status changes. And yet the problem persists. Someone saw the signal but didn’t know if it was their responsibility. Someone arrived too late. A third person fixed the symptom, not the cause. The technology worked—the people, not necessarily. This happens when the implementation of the system is not accompanied by the parallel implementation of response procedures. And changing the organizational culture in manufacturing starts with three specific decisions.
This application is just the beginning
From the very beginning, Toyota understood that the effectiveness of the Andon system is not a matter of equipment—it is a matter of organizational behavior. One of the most commonly identified causes of low implementation effectiveness is the lack of a defined Andon response protocol. [1] The operator signals a problem, but the system—human, not technical doesn’t know what to do next. Who should come? When? What will they do if they can’t solve the problem on their own? Without answers to these questions, even the best digital system becomes nothing more than a log of unresolved incidents.
This is not a technical problem. It is an organizational and cultural problem.
The three pillars of a culture of response
Implementation practices and the relevant literature point to three conditions without which an Andon system will not deliver the expected results—regardless of how good the technology is.
Clearly defined responsibility
Every signal must have an owner. Not “the UR department,” not “the shift foreman”—a specific person who knows that this is their task and that their response time is being measured. Research on Lean implementations in manufacturing environments shows that effective alert escalation systems in production require a precisely defined responsibility matrix: who responds to a given type of event, within what timeframe, and who takes over if the first person does not respond. [2] In a digital system, this translates directly into the configuration of notification routing rules—a machine failure goes to the mechanic, a material shortage to logistics, and a quality issue to quality control. In practice, the absence of this configuration means that an alert about a machine failure goes simultaneously to the mechanic, the foreman, and the manager—and each of them assumes that someone else will handle it.
Standard response time with automatic escalation
Best practices specify a concrete timeframe: a maximum of two minutes from the time a report is submitted until it is acknowledged by the responsible person, after which it is automatically escalated to the next level. [3] Not as a punishment, but as a systemic safeguard. Response time to production failures is one of the key performance indicators for the maintenance department—and this is where digital Andon makes the biggest difference. In the analyzed implementations, the time from reporting to the technician’s arrival at the workstation was reduced by up to 60% thanks to digital routing and automatic escalation. [3]
A Blame-Free Culture
This is the most difficult element, and at the same time the most important one. Facilities that punish employees for reporting problems or stopping the line incur a double cost: an overt one—downtime—and a hidden one—a significant portion of problems that go unreported out of fear of consequences, as confirmed by observations from implementations described by Lean practitioners. [1] Research on organizational culture in manufacturing confirms that employees who have experienced negative reactions to their reports eventually stop using the Andon system altogether. The result: falsely low failure statistics and very real, hidden losses.
From Signal to Insight: What Industry 4.0 Is Changing
This is where the real change brought about by digitalization begins. An analog light simply indicated that something was happening. An Industry 4.0 digital system tells you: what is happening, where, how long it has been going on, who is responsible, and whether this is the third time this week.
The data left behind after each incident
Every report processed through the digital system leaves a trail: time of occurrence, workstation, response time, resolution time, and person responsible. Individually, these are incidents. Collectively, they form the knowledge and foundation for continuous improvement (Kaizen). A study conducted in the Peruvian textile sector showed that the implementation of Andon, combined with work standardization and error-proofing tools, reduced the defect rate from 12.70% to 6.71%—by nearly half. [5] The study’s authors note that this result was achieved by combining the signaling system with standardized response procedures and root cause analysis for each report.
From Reaction to Prevention
A plant that analyzes its Andon event history begins to see patterns invisible to the naked eye: which machine generates the most alerts during the third shift, which workstation has the longest response time to production failures, and where a problem recurs every two weeks because the symptom is being fixed instead of the root cause. Integration with IIoT systems allows an event to be linked to machine parameters at the moment it occurs and enables preventive planning rather than firefighting—provided that the data is systematically analyzed and translated into a maintenance schedule. As Florescu and Catana point out in the context of lean-based management in Industry 4.0: the integration of advanced technologies into the Andon 4.0 concept is the driving force behind the modernization of production management toward full interconnectivity. [6]
A culture of response and access to data are two sides of the same coin. The first says: take action now. The second says: make sure it doesn’t happen again. The system can enforce this process, but the decision about who is responsible and when must be made by management.
A tool without a response culture is like a streetlight on an empty road—it shines, but no one is driving by. Facilities that view Andon not as a technology but as a system of accountability achieve more than just reduced downtime and more effective Lean-based production management. They build an environment where problems come to the surface instead of being swept under the rug, and where every report—instead of causing stress—triggers a smooth, predictable chain of actions. Systems like AndonCloud allow you to configure this chain yourself—notification routing, production alert escalations, and event logs—without having to involve external integrators. But no software can replace the decisions that management must make.
Sources and Bibliography
[1] Mohamad E. et al. (2019) — Framework of Andon Support System in Lean Cyber-Physical System Production Environment, Manufacturing Systems Division Conference, DOI: researchgate.net/publication/336042593
[2] Li J. & Blumenfeld D.E. (2006) — Quantitative Analysis of a Transfer Production Line with Andon, IIE Transactions, 38:10, 837–846, DOI: 10.1080/07408170600733228
[3] Fan J., Hao H., Xu Y. (2024) — Application and Optimization of Deep Learning-Powered Intelligent Andon System in Lean Manufacturing — CAICE 2024, ACM. DOI: 10.1145/3672758.3672786
[4]Kiukkonen R. (2025) — Improving internal material flow between warehouse and production with lean principles — LUT University
[5] Huayra-Mendoza G.F., Ticlavilca-Arias K.C. (2024), Comprehensive Lean Production Model Implementation for Quality and Efficiency Enhancement in Textile SMEs: A Case Study, 1st World Congress on Industrial Engineering and Operations Management, pp. 102–116
[6] Florescu A., Catana A.E. (2025), Lean-based management in process improvement projects in Industry 4.0, RECENT, Vol. 26, No. 3, pp. 354–362
What You Should Know About the Response Culture in the Andon System
Does the Andon system work without a change in organizational culture?
Technically, yes—the signals will be sent. But the effectiveness of the Andon system will be limited. If employees are afraid to report problems or don’t know who should respond, even the best system will go unused. Technology creates opportunities; the organizational culture in manufacturing determines whether they will be utilized.
What does “a blame-free culture” mean in the context of the Andon system?
It is an environment where an operator reporting a problem is seen as someone who helps—not someone who causes trouble. Plants that penalize employees for reporting issues or stopping the line quickly stop receiving reports. The result is falsely good statistics and very real, hidden losses.
Who should be responsible for responding to an Andon signal?
It depends on the type of incident. Machine failure—maintenance department. Material shortage—logistics or warehouse. Quality issue—quality control. It is crucial that each type of incident has a predefined owner, rather than ending up in a general “someone will handle it” queue.
How long should the response time for production failures be?
In the most effective implementations, a maximum of two minutes is allowed for acknowledging a report. After that time, a well-configured system automatically escalates the issue to the next level. This isn’t a punishment—it’s a safeguard to prevent the problem from escalating unchecked.
How does “fixing the symptom” differ from “solving the problem” in the context of Andon?
Fixing the symptom means getting the machine back up and running without investigating why it stopped. Solving the problem involves analyzing the root cause—e.g., using the 5 Whys method—and implementing a measure to prevent recurrence. The Andon system provides data for this analysis: time, frequency, patterns. Without it, the same machines will keep stopping over and over again.
Can data from the Andon system be used to evaluate employees?
With caution. Data on response times to production failures can be a valuable metric for leaders, but it should not be used for punishment. Used wisely, it helps identify areas where support or training is needed. Used thoughtlessly, it destroys trust and discourages problem reporting.
How does a digital Andon system support a culture of responsiveness?
Through automation and transparency. The digital system records every event with an exact timestamp, assigns it to a specific person, and measures response time. Alert escalations in production occur automatically—eliminating situations where a signal is ignored because no one felt responsible for it.
Why do Andon system implementations often fail despite good technology?
The most common reason is the lack of an Andon response protocol and responsibility assigned too broadly. When a notification goes out to everyone at once, no one feels ownership of it. The digital system solves this through precise alert routing the right person, the right moment, and automatic escalation if there is no response within a specified time.
Does implementing a response culture take a long time?
Changing the organizational culture in manufacturing is a process, not a project with an end date. But the first results are visible quickly: when employees see that their reports are received, acknowledged, and resolved within a predictable timeframe, trust in the system grows. The first few weeks after implementation are crucial—that’s when the plant sends a signal as to whether Andon is a tool that really works or just another initiative that will fade away after a month.
