Andon

Origin. Toyota Production System; andon means "lantern" — a visual signal.

Mechanism. Status is made visible to everyone through physical signals — lights, boards, displays. When a worker encounters a problem, they activate the andon (typically by pulling a cord); the signal summons help and may stop the line. The public visibility creates accountability and enables rapid response. Information radiates rather than requiring extraction.

Procedure. Install visible displays showing process status. Define the signals: green (normal), yellow (attention needed), red (stopped). Empower every worker to activate the signal. When activated, the responsible party responds immediately. Track signal frequency and causes; high-frequency signals indicate systemic issues. The andon is not the solution; it is the call for help that initiates problem-solving.

Applies to. Manufacturing, operations centers, software deployment (build radiators), any environment where status must be communicated continuously to multiple parties.

Limitations. Andon as surveillance rather than support. If activating the signal brings blame rather than help, workers will not activate it. The response to andon must be assistance, not inquisition. Also: signal fatigue from too many signals or signals that do not correlate with actual problems.