What does a green filter arrow at traffic lights mean in Northern Ireland?

A green filter arrow allows traffic to move in the direction shown by the arrow, provided the way is clear.

The NI traffic-light guidance says the arrow can permit that movement even while other signal aspects are showing for different movements.

For “What does a green filter arrow at traffic lights mean in Northern Ireland?”, the wider Northern Ireland context is this: Northern Ireland's Highway Code uses signs, signals and road markings together, so the safest reading is always the exact sign at the location plus any lane arrows, plates or temporary traffic management. Rules expressed as ‘must’ or ‘must not’ are legal requirements; advisory wording can still be used as evidence when responsibility for a collision is considered.

For this exact question — “What does a green filter arrow at traffic lights mean in Northern Ireland?” — the practical point is: Follow only the direction of the arrow, check for pedestrians and other permitted traffic, and do not assume every direction has a green signal. The answer should be applied to the actual signs, conditions, licence wording or parking rules in force at the time, because temporary restrictions and individual DVA decisions can change the ordinary position.

This Northern Ireland-specific page on “What does a green filter arrow at traffic lights mean in Northern Ireland?” was checked against the attached official sources before publication, with nidirect/DVA and the Northern Ireland Highway Code used ahead of generic UK motoring articles. If the rule, road layout or personal licence condition changes, those primary sources are the ones to re-check.