Pass Either Side vs Turn Left Only

Understanding the subtle yet vital difference between these blue regulatory signs can make all the difference—especially for learner drivers mastering theory and practical tests. Let’s set them out clearly, in traditional style, grounded in DVSA standards.
1. Pass Either Side of Obstruction (Blue Circle, Two Arrows)

Appearance:
A solid blue circular sign featuring two white arrows—one pointing down-left and the other down-right—around a central obstruction

Meaning:
This sign indicates that you may pass the obstruction on either the left or the right. It is typically used where an island, bollard, or central obstruction exists.
- It does not confer priority—it simply gives you the choice.
- It is not a suggestion; it’s a mandatory directive to pass safely on either side.
- Generates less confusion than expected, but remains one of the more misunderstood signs

Memory Aid:
Two arrows = two pathways. You have the freedom to choose; just stay alert and safe.
2. Turn Left Only (Blue Circle, Single Arrow)

Appearance:
A blue circular sign featuring a single white arrow pointing left
Meaning:
This is a mandatory direction sign—you must turn left. No other directions (straight or right) are permitted.
- You’ll often find this at junctions or T‑junction layouts where road geometry requires a left-only movement.
- Disregarding this is not just careless—it’s illegal

Memory Aid:
One arrow = one way. Left only—no deviation allowed.

3. Quick Comparison Table
Sign | Appearance | Meaning | Rule Type | Driving Response |
---|---|---|---|---|
Pass Either Side | Blue circle, two arrows | Pass obstruction on left or right | Mandatory choice | Choose either side safely |
Turn Left Only | Blue circle, single arrow left | Must turn left | Mandatory directive | Turn left only—no alternatives allowed |