Sunday, July 26, 2009

Driving test - hazard perception test

Hazard perception test forms a second section of the theory test and must be passed at the same time. Integrating theoretical hazard perception test training into the practical training sessions will ensure that as competence is achieved in each of the necessary skills, they can be strengthened and applied while you are on the road to increase the road safety benefits.

This part of the theory test requires you to view 14 hazard video clips on the computer screen of approximately one minute each. You are required to watch these clips as if you were the driver. There will be 15 hazard to find - at least one on each clip. However, one clip will have 2 hazard. The hazard perception test clips will not contain any sound.

The clips feature various types of hazard, such as vehicles, pedestrians and road conditions. You should respond by pressing a mouse button as soon as you see a hazard developing that may result in the driver having to take some action, such as changing speed or direction.The earlier the developing hazard is spotted, and a response made, the higher the score. Candidates can score up to five marks on each hazard and the test contains 15 scoreable hazard.

You click either the left or right mouse button whenever you think you can see a hazard developing. The speed at which you click the mouse button as a hazard develops will determine your score for that particular hazard perception clips. You can score between 0 and 5 on each hazard The pass mark for this part of the test is 44 out of 75 (i.e. 15 hazard x 5) for car drivers and motorcycle riders. Those taking LGV or PCV (lorry or bus) tests must score at least 50 out of 75. Candidates are given their results when they have finished both parts of the test and have returned to the waiting room.

Hazard perception test process:

Each hazard perception clip will start with a freeze frame of the start of the video sequence and a count down from 10 will commence. At the end of the count down the clip will start to play and you will be required to click the mouse button each time you see a developing hazard. To let you know that the program has registered your click a red flag will appear on a grey band across the bottom of the screen - one flag for each click you make in any particular clip. At the end of the clip all the flags will be removed before you start the next clip.

An example when to respond:

As an example, of how to identify and respond to a developing hazard, consider a parked vehicle on the side of the road. When you first see it, it is not doing anything; it is just a parked vehicle. If you were to respond to the vehicle at this point, you would not score any marks, but you would not lose any marks. However, when you get closer to the vehicle, you notice that the car's right hand indicator starts to flash. The indicator would lead you to believe that the driver of the vehicle has an intention of moving away, therefore the hazard is now developing and a response at this point would score marks.

The indicator coming on is a sign that the parked vehicle has changed its status from a potential hazard into a developing hazard. When you get closer to the vehicle, you will probably see the vehicle start to move away from the side of the road; another response should be made at this point. Different clips in the test will have various signs to indicate that the hazard is changing its status and is now starting to develop.

Hazard perception online test scoring mechanism:

How the scoring mechanism works ?

Each scoring window is divided into five equal segments and a score of five through to one allocated to each. Those responding in the first segment of the scoring window will score 5 and those in last segment a score of 1. Responses outside the window will score zero.

If you click the mouse while in the first segment (i.e. just as the developing hazard appears) you will obtain the maximum score of 5 points. If you click in the second segment of this window of time you will score 4 points, then 3, then 2 and then in the last segment just 1.This is accurate to one twenty fifth of a second.If you click the mouse button (this is how you inform the computer that you have seen a hazard) too early, before the potential hazard becomes what the DSA term a developing hazard.

Your score will be 0. Therefore to ensure you get a maximum score in the hazard perception test challenge you should fully understand the DSA term developing hazard as opposed to potential hazard. If you click several times during this window of time the computer will always take your highest score and record that for that particular clip.

If you don't click the mouse button in this window of time you will score nothing in respect to that hazard. If lots of unnecessary responses are made in a very short space of time, or throughout the clip, a zero score will recorded for that clip. If this happens a warning message will be shown on the screen at the end of the clip. When the clip ends the screen will turn black for a few seconds before the freeze frame for the next video clip appears and the count down commences again, warning you to get ready. This pattern is repeated until all 14 video clips have been shown.

Click to check how hazard perception test score is calculated:

hazard perception test free clips hazard perception test challenge - Hints and tips

Although each clip contains several potential hazard only the one that materializes
into a real hazard (one clip will have 2 hazards) and involves other road users is marked. This is known as a developing hazard. Therefore you will only receive a score if you spot a hazard before it fully materializes and is brought about by the action of another road user. In a few instances it is difficult to determine when a potential hazard becomes a developing hazard and therefore when the scoring window should start.

This is why it is safer to click a few times as you see a hazard develop to make sure you don’t click too early and miss the opening of this window. Recognition of available clues and perception of danger are skills that are necessary in all drivers and riders, irrespective of the vehicle used. For this reason, the same version of the hazard perception test is used for all categories of test.

Look for these hazards
  • pedestrians or cyclists crossing the road
  • vehicles emerging from side roads, parking places or driveways
  • large vehicles moving over to your side of the road
  • meeting oncoming vehicles on narrow roads or where other obstructions or slow moving vehicles make the road narrow
  • loose pets and farmyard animals
  • changes in the traffic movement and volume
  • junctions and roundabouts
  • horse riders
  • weather conditions of the day
  • road surfaces
  • parked vehicles
  • hidden junctions & turns