Approaching a junction where a side road forks off to the left, you see a small blue circular sign with a single white arrow pointing straight up, fixed on a post just before the give-way markings. What does this sign require of your car specifically at this junction?
- You must continue straight ahead; turning into the side road is not permitted for your car
- You may turn either direction, but through traffic must give way to vehicles emerging from the side road
- The sign is advisory only; it recommends going straight ahead if convenient, but any direction is permitted
- You must stop completely at the sign before proceeding, regardless of which direction you intend to travel
Why A? And why not the others?
Correct answer: A. You must continue straight ahead; turning into the side road is not permitted for your car
The blue circle carries a mandatory, not merely advisory, instruction, and when it shows a single upward arrow it means ahead only: every vehicle must continue in that direction and cannot turn into the side road at this specific point, distinguishing it from a red circular sign, which prohibits a movement rather than compelling one. Describing the sign as allowing free choice of direction misreads a blue mandatory circle, which by definition narrows the driver's options; it is not a permissive both-ways instruction. Treating the sign as merely advisory ignores that blue circular signs give legally enforceable positive instructions, the mandatory counterpart to the prohibitory red circle family, so a driver cannot lawfully disregard it just because turning seems convenient. Requiring a full stop confuses the sign with the entirely different octagonal STOP sign; an ahead-only sign carries no stopping requirement of its own, only a direction requirement, so a driver already moving straight through simply continues without needing to halt.
Source: The Highway Code: Traffic signs — signs giving orders (GOV.UK), mandatory direction signs