Traffic light rating system

A traffic light rating system is a system for indicating the status of a variable using the red, amber, or green of traffic lights.

Food may be labelled with a traffic light label showing how much fat, saturated fats, sugar, and salt are in that food by using the traffic light signals for high (red), medium (amber) and low (green) percentages for each of these ingredients. Foods with 'green' indicators are healthier and to be preferred over those with 'red' ones. The label is on the front of the package and easier to spot and interpret than Guideline Daily Amount (GDA) labelling which will continue. The GDA is difficult to understand for many, including children, and does not lend itself to quick comparisons. The use of traffic light labelling is supported by many physician groups including the British Medical Association and welcomed by consumers. Despite worries from some in the food industry that red foods would be shunned, the British Medical Association, Food Standards Agency and others agree that consumers interpret the labels sensibly, realise they can have red foods as a 'treat', and they are easier to understand than lists of percentages.

Currently the traffic light label is used in some European countries on a voluntary basis.

White goods must be labelled with a label indicating energy consumption. This is not strictly a 'traffic light' but by analogy a scale of seven values that run from red to green through intermediate colours.

The system may also be used for the European Game Information System (PEGI), which puts age ratings onto video games. Again this is not strictly a 'traffic light' since there are likely to be more than three colours.

In many factories, different stations on the production line(s) are equipped with factory monitoring and control systems; attached to such systems is a 'traffic light' status indicator which is generally visible from many places within the factory. Green typically indicates normal levels of production; amber indicates that production has slowed (or attention is otherwise warranted); red indicates that production has stopped or the line is down.

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