Yellow Box and Green Arrow on the Spintex Road
It is 06:55 on a weekday on the Spintex Road, approaching a signal-controlled crossroads. You are in the right-hand lane, intending to turn right. The signal shows a full green disc together with a green right-turn arrow. Just beyond the stop line lies a yellow box junction; about 20 metres past the box the road you want to enter is stationary, with a queue of cars that has not moved for a minute. Oncoming traffic is heavy and continuous. Pedestrians are crossing the side road on your left. The taxi behind you is sounding its horn and edging forward. The light has now been green for around 20 seconds and your exit is still blocked.
1. May you drive into the yellow box junction? Explain the rule you are applying.
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No. The box is a keep-clear area: you may enter only if your exit from the box is clear and you can cross it without stopping. A green light gives you permission to cross the stop line, not permission to stop inside and block the junction.
There is one recognised exception. When you are turning right, you may wait inside the box if you are held up only by oncoming traffic or by other vehicles also waiting to turn right. That exception applies to traffic you are yielding to, not to a blocked road on the far side.
Here the obstruction is a stationary queue beyond the box. The exception does not cover it. You stop at the stop line and wait, even though the light is green and the taxi behind is impatient. A green light with a blocked exit is not an instruction to enter.
2. What does the green right-turn arrow add to the full green, and does it change your answer?
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The full green means you may proceed but must give way to oncoming traffic when turning right. The arrow indicates a protected movement: traffic that would conflict with your turn is being held by its own red, so oncoming vehicles should be stopped and you may turn without yielding to them.
The arrow therefore changes what you expect from other traffic, not whether you may enter the box. It does not suspend the keep-clear rule, it does not excuse stopping where you would block the junction, and it does not remove your duty to give way to pedestrians already on the crossing. Since the blockage is the queue beyond the box, your answer stays the same: wait at the line, on the arrow or not.
3. Suppose you began the turn on the arrow, then could not complete it, and the light changes to amber and then red while you are in the junction. What now?
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You have already crossed the stop line lawfully, so the red does not require you to stop dead in the middle of the junction. Complete the movement as soon as it is safe and clear the junction; do not reverse, and do not sit across the box. Reversing out of a junction is far more dangerous than finishing the turn.
Two things got you here and both are worth naming. First, entering on the arrow before confirming that a car's length existed on the far side - the gap should have been checked before committing. Second, pressure from the taxi's horn, which is not a reason to move.
While you are clearing, keep the indicator on, watch for pedestrians crossing in front of you as you turn, and do not accelerate hard to 'get out of the way' - the priority is clearing the junction without a second conflict.