Potential and developing hazards
The single distinction the hazard perception test is built on, and why only one of the two scores anything.
Almost everyone who struggles with hazard perception is struggling with one distinction. Get this right and the rest is practice.
Three kinds of hazard
Static hazards
Fixed features of the road: a bend, a junction, a brow, a narrow bridge, roadworks. They never move and they are entirely predictable, which means there is no excuse for being surprised by one. They do not score in the test.
Potential hazards
Something that could cause a problem but has not started to yet: a parked van, a pedestrian on the pavement, a side road, a car waiting at a junction, a cyclist ahead.
Potential hazards do not score either. What they do is tell you where to look.
Developing hazards
A potential hazard that has started to change in a way that will require you to do something — slow down, change direction, or both.
These are the only ones that score.
The test in one sentence
Click at the moment a potential hazard becomes a developing one — not when you first see the object, and not when the problem is unavoidable.
The same object, three states
| Scene | State | Scores? |
|---|---|---|
| A van parked at the kerb ahead | Potential — it hides whatever is behind it | No |
| A ball rolls out from beside the van | Developing — a child is about to follow it | Yes |
| A child is in the middle of your lane | Too late — the scoring window has closed | No |
Notice that the scoring moment is the ball, not the child. That is the whole skill: responding to the evidence that something is about to happen, rather than to the thing itself.
Why they test it this way
A driver who reacts when a child is already in the road is a driver who brakes hard and hopes. A driver who reacts to the ball has already lifted off, already covered the brake, and probably stops without drama.
Every point in this section is measuring the gap between those two drivers, in fifths of a second.
Common examples of the change
- A parked car's brake lights come on, or its front wheels turn out.
- A pedestrian on the pavement turns towards the road or steps off the kerb.
- A car waiting at a junction edges forward, or the driver looks away.
- A cyclist looks over their shoulder — they are about to move out.
- Brake lights come on several vehicles ahead.
- A lorry indicating left moves out to the right to make the turn.
Next: where to look for these clues, then how the scoring window works.
Sources checked for this page
- GOV.UK — theory test
- Driving — The Essential Skills — Hazard awareness
We summarise official guidance in our own words. Where the rules matter legally, check the official source. This site is not affiliated with DVSA.