What do Andon Colors represent?
Andon Color Codes
Andon lights have multiple colors to represent statuses of an operation. Most manufacturing environments share a similar convention for what each color means, but it varies depending on the application. This guide covers different standards for andon light color codes, how they vary by industry, and how to set up a color system that works for your facility.
Standard Andon Light Colors
Most signal light systems use a combination of five colors. Each color communicates a different machine or process status. Here is the most common breakdown:
| Color | Standard Meaning | Typical Use |
|---|---|---|
| Green | Normal / Running | Machine is operating normally and producing parts. Everything is good. |
| Yellow / Amber | Caution / Attention Needed | Material running low, minor issue detected, changeover due, or preventive maintenance needed. |
| Red | Stopped / Fault / Error | Machine is down. Could be an error code, equipment failure, safety stop, or quality reject. |
| Blue | Operator Request | Operator needs something: materials, a supervisor, a quality check, or technical support. |
| White / Clear | Setup / Informational | Machine in setup mode, cycle complete, or a custom condition specific to your process. |
Green, yellow, and red are nearly universal. Blue and white vary from one facility to another, often being used as a custom signal for a specific operation.
Is There an Official Standard?
There is no mandatory standard for Andon light colors. However, IEC 60073 is commonly used across many industries.
- IEC 60073 - An international standard that defines color coding for indicator lights and push buttons. It recommends red for danger/emergency, yellow for warning/abnormal, green for safe/normal, blue for mandatory action, and white for neutral/informational.
In practice, most facilities align with IEC 60073 whether they reference it or not. The color associations are intuitive: green means go, red means stop, yellow means caution.
Common Industry Variations
Automotive Manufacturing
Automotive plants tend to follow strict Andon protocols. Green means the station is running within takt time. Yellow (or Amber) signals a call for help, often triggered by a pull cord. Red means the line has stopped. Blue is sometimes used for quality holds or material requests.
Food and Beverage
In food processing, red often indicates a sanitation or safety stop. Yellow can signal a changeover between product runs. White is sometimes used for CIP (clean-in-place) cycles. The priority is traceability and compliance with hygiene standards.
Warehousing and Logistics
In warehouse environments, tower lights on conveyor systems or pick stations may use green for "station active," red for "jam or fault," and blue for "supervisor needed." The focus is on keeping material flow moving.
CNC and Machining
Machine shops often use green for spindle running, yellow for tool change or program pause, and red for fault or alarm. A 4th tier (blue or white) can signal cycle complete so the operator knows to return and unload the part.
Setting Up Your Own Color Scheme
The most important thing in setting up your own andon color system is consistency throughout your operation. Every machine and workstation in your facility should use the same color meanings so operators do not have to guess.
- Start with the basics. Green for running, yellow for caution, red for stopped. This covers most situations and matches what people already expect.
- Add colors when needed. If operators need to signal for help, add blue. If you need a "setup" or "idle" state, add white.
- Define flash vs. steady. A flashing light will stand out amongst steady lights. A common approach is to use flashing for red only.
- Include the buzzer. If your tower light has a buzzer, define when it sounds. A common choice is buzzer on red only.
- Display the color meanings. Put copies of the color code reference at many stations throughout your facility. This is especially helpful for new employees and visitors.
Tip: If you are deploying Andon lights across multiple lines or facilities, document your color code standard in writing and share it with your maintenance and engineering teams. Consistency across the plant is what makes the visual factory concept work.
Learn More
For related topics, check out these guides:
Need Help With Your Setup?
We configure Andon light systems every day and can help you plan the right color scheme for your facility. Give us a call and let us help with your project.