Andon gives every employee the power and duty to signal problems immediately — and obliges a defined help chain to respond within minutes. The lamp is the least of it; the response chain is the system.
The response chain is defined and staffed: who comes first, within how many minutes, and who is the next link
The cultural agreement is explicit: pulling the cord is DESIRED behaviour — even when the alarm turns out to be false
The signal types are few and unambiguous (e.g. quality / technical / material)
When MUST a signal be raised: a defective part, a deviation from the standard, a risk of a stop, a safety observation. The criteria must be so clear that doubt falls out to signalling — “better one call too many” is a rule, not a platitude.
A cord, button or flag + light/sound + visibility for the help chain. The technology is secondary; a laminated red/green flip can start the pilot. Most important: the signal must be seen/heard by those who are to respond — not just recorded in a system.
First response (team leader) within X minutes — a physical arrival, not a phone answer. If the problem can’t be solved within the agreed time, it is escalated automatically to the next link. The chain is documented visibly at the line, with names per shift.
The first sentence on arrival is standardised: “Thanks for calling — what do you see?” Never “why have you stopped?”. The first weeks’ responses decide the system’s life: one irritated leader at a false alarm, and the cord rusts.
Each signal is logged briefly (time, cause, response time, solution). A weekly Pareto on the board: the most frequent signal causes get a 5 Whys/A3. The goal over time is fewer NECESSARY signals — never fewer signals through restraint.
How it goes wrong in practice — and this is where most implementations part ways.
The signal lights, no one comes, the operator solves it themselves as always — and the system is dead after two weeks, now with documentation that no one comes.
When “many calls” is read as poor performance, people stop calling — and the problems go underground again. Celebrate calls that caught something early.
Eight colours and five sounds: no one remembers the code, and hesitation eats the point. Two or three types are enough.
The method only works when it becomes daily routines and leadership behaviour. The operations check shows in 4 minutes where your operations stand — and what should come first.