Unfamiliar four-arm junction with a stopped bus
You are driving in an area you do not know, approaching a four-arm junction controlled by traffic lights. Your light has been green for some time. A large bus is stopped in the left-hand lane just beyond the junction, facing your direction, with its hazard lights on and passengers standing near the kerb. The right-hand lane beyond the junction is clear for about 50 m. A car is close behind you, and a van is waiting to emerge from the road on your right. The junction box is marked with yellow cross-hatching. Rain has just started and the road surface is greasy.
1. How would you decide whether to proceed through the green light, and what would you check before entering the junction?
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A green light gives permission, not an obligation. Before entering I would check that the exit is clear enough to take my car completely through, because stopping in the yellow box would block the junction. The bus is the key problem: it is stopped just beyond the junction with hazards on, so the left lane is effectively closed. I would check the right mirror and blind spot, signal right if safe, and plan to move into the right-hand lane to pass the bus, using the clear 50 m beyond the junction. I would also check the van on my right, since it may try to emerge if it misreads the lights or if its own signal turns green. Because the road is greasy, I would reduce speed before the junction and increase my gap, avoiding any sudden braking that could cause the car behind to run into me.
2. What are the risks created by the bus, its passengers and the car close behind, and how do you manage them together?
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The bus creates three hazards: passengers may step into the road, the bus may pull out or open doors, and its bulk hides pedestrians crossing in front of it. The car close behind limits how hard I can brake, so I need to slow early and progressively, using the mirrors to judge its distance. My plan is to reduce speed well before the bus, signal my lane change early, and pass with a wide margin, watching under and around the bus for feet and shadows. I would not overtake the bus on the left where passengers are standing. If the right lane is not clearly safe, I would stop behind the bus at a distance that leaves me an escape route, rather than squeezing past. Managing the hazards together means choosing one action, a controlled lane change, that solves the bus problem without creating a braking problem for the car behind.
3. The rain has just started and the surface is greasy. How does this change your speed, gap and braking through the junction?
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Fresh rain on a dry, dirty surface lifts oil and rubber, so grip is at its worst in the first minutes. I would reduce speed by roughly 10 to 20 km/h below what I would use in the dry, extend my following gap, and brake earlier and more gently, using light progressive pressure rather than a late stab. Through the junction I would avoid sharp steering inputs, especially while crossing the painted markings, which are slippery when wet. I would keep both hands on the wheel, ensure the wipers and lights are on, and check the mirrors more often because spray reduces what I can see and what others can see of me. If the car behind is still too close, I would increase my own gap ahead so that any braking I do is gradual, giving that driver more time to react.