At every junction, a driver leaves one road and turns into, crosses or joins another one. This is what 'emerging' means. In Chapter 6, we have explained how a driver should deal with a junction up to the point at which he must look and stop, if necessary. But what exactly should he look for and how does what he sees enable him to decide whether to wait or go on ?

The most obvious thing to look for is the approach of traffic, particularly from the right, which is the greater danger. The decision to stop is sometimes made for you by STOP signs or traffic signals, or by a policeman or traffic warden. At other places, you will have to wait for a gap in a stream of vehicles to join or cross a road. At other times GIVEWAY signs and/or lines will remind you of the particular need to judge the speed and course of other vehicles. GIVE WAY does not necessarily mean that you must come to a stop. But you must let  vehicles on the major road go first, and not enter the junction unless and until you can do so without getting in their way.

If you have stopped at a junction, then you have to make a second decision: When is it safe to go on? Even when traffic is controlled by signals, the green light means only that you may go on if the way is clear. You must still take special care, and in particular, you should give way to pedestrians who are crossing. The same rule applies to the 'moveon' signal of a policeman or traffic warden.

Therefore, at any junction you have to decide whether to wait or go and when to go, if you wait. In all cases, you need to have a full view.

A driver's field of view enables him to see a stretch of the road in front and behind him. His vision is normally limited by various obstructions on the road, parts of his vehicle and weather conditions, making it necessary for him to slow down or even stop.

Coming up to a junction is, rather like running into a patch of fog. Consider the extreme case of a driver approaching a blind corner in a narrow street, with a lorry or bus behind him. In front he can see only a strip of the road he is to enter and behind, only a large radiator. This can occur on any road, wide or narrow, when a stream of traffic is approaching a junction. In fact, road junctions are always the places where vision tends to be poor. Yet a good view into the other roads of the junction is essential. This view is called the 'zone of vision'.

Although the zone of vision gets wider as you get nearer the junction, it is surprising, as to how close you must be before it widens enough for you to see far enough into the other roads. Figs show why the last few feet are so critical in giving you your zone of vision.

It is not always easy to judge the speed and distance of an approaching vehicle, especially if it is coming straight towards you. It is a little easier, if it is coming at an angle or on a curve. Remember that if the vehicle is coming downhill, it may be travelling faster than  you think. On the other hand, don't expect it to be crawling just because it is coming uphill.

Don't forget that there may be other vehicles quite close that you can't see. Watch out for 'dead ground' where the road dips and a car can be hidden. An example of this is  shown in Fig. Look out for overhanging leafy branches, which can hide a considerable stretch of straight road. Again, a car parked off the road can hide oncoming vehicles at a junction. This is really an obstacle point, but a car may come up and park while you are waiting at a junction, so be ready to re-assess your zone of vision and to move as necessary.

Finally, remember that poor weather conditions can complicate the whole business of looking at a junction, however wide and full your zone of vision would otherwise be. So take particular care to make sure before going on.

You have to get to a position from where you can clearly see into a junction to answer the question: 'Wait or go on?' If there is a vehicle coming from the right, which is very close, you should stop and wait. It may be equally important that any approaching vehicles be so far off that you can go on with perfect safety. In case of doubt for safety, you should stop and wait.

You must be careful to join or cross the path of an oncoming vehicle only when it is far enough to make it quite safe for you. Forcing other drivers to change their plans is a dangerous business. This is very much our basic practical message: Stick to the rules and everybody concerned knows what to expect. At junctions, the rules really mean that you should adjust your speed and/or position to be prepared to fit in safely and if that is not enough, you should stop and wait.

Having decided that it is safe to emerge at the junction, you go forward on to your 'new' road. At once you will have another set of questions to answer. They will include:

The answers to all these questions concern position and speed. This gives us the full routine (MSM and PSL) for dealing with a junction. Get in the habit of using this routine at all junctions. It will serve you well.

It may be very tempting when turning right on to a wider road to drive along the centre of the road and join the left stream, especially when there is little traffic from the right. This is very risky. First, you will confuse drivers behind you. Second, the road may become narrow, or there may be junctions or islands in the road ahead. Third, there may be no gap for you to fit into. So don't create an extra stream in this way.

You may also be tempted to pull into the centre of the road and wait there to complete the turn. This is also very dangerous unless the centre divider is conveniently wider than the length of your vehicle or the road is specially marked to allow it.

Turning into a road to right or left :

If you are going to turn to  the  left,  watchout especially for cars parked, or about to stop on the left. You may get trapped behind them. Be very careful to look for cyclists or motor-cyclists coming up on your nearside.

If you are turning to right, getting your position and speed correct is vital. You must look for traffic on both the roads you are joining and leaving. Don't cross oncoming traffic until you can do so without causing it to change speed or direction. Be very careful where you stop and wait, because some of the oncoming vehicles may be turning right too.

There are some wider junctions where it is more convenient to pass nearside to nearside, but this is less safe because the oncoming vehicle hides the view of the driver. The usual rule is offside to offside, but watch out for junctions where police control or  road markings mean that you are intended to turn nearside to nearside.

At a staggered junction as that shown in Fig. you cannot turn right behind an oncoming vehicle that is also turning right (offside to offside). So be on the look-out for traffic hidden behind the leading vehicles and be ready to stop.

These can be deceptive because some call for little change of direction. But if two drivers are approaching a junction on two different roads of 'Y' junction and don't realise its importance, one at least will have to take very sudden and therefore, dangerous action. Apply the PSL routine at 'Y' junctions as you would at any other junction.

Always be on the look-out for pedestrians and remember these two rules: At pedestrian rossings controlled by lights or police give way to pedestrians, who are crossing when the signal to move is given. When turning at a road junction always give way to pedestrians who are crossing the road.

Roundabouts help traffic flow by mixing together several streams of vehicles. But this very function creates a situation in which a high level of information and anticipation is needed. The rules to remember are: the GIVEWAY rule, to decide whether to wait or go on; and the 'driving procedure' rules, to decide how to approach the roundabout and what course to take in it.

The GIVE WAY rule says that when you approach a roundabout, you should normally give way to traffic from your immediate right to avoid causing any approaching driver to reduce speed, to alter course or to be put in any danger.

Since this is a general rule, upright GIVE WAY signs (on posts) are not placed at all roundabouts but the points of entry are marked by single broken white lines on the road.

The following rules should always be observed unless road markings indicate otherwise or the approach road and the roundabout itself are quite free of traffic.

Approach in the left-hand lane; keep to that lane in the roundabout and leave by it. Use the left-turn indicator on approach and through the roundabout.

Approach in the left-hand lane; keep to that lane in the roundabout. Use the left-turn indicator at the exit before the one you are going to take. If conditions dictate,  approach in the right-hand lane and keep to that lane in the roundabout. Use the left turn indicator at the  exit before the one you are going to take.

Approach in the right-hand lane; use the right-turn indicator before entering the roundabout and maintain this signal while keeping to the right-hand lane in the roundabout; change to left-turn indicator at the exit before the one you are going to take.

If you stick to these signals, you will be letting other drivers know what you are going to do. And if they are observing the rules too, you will know what they are going to do. But note that they are not hard and fast. You need to weigh up the situation and apply a degree of common sense. As said earlier, roundabouts are places where traffic streams mix. So be prepared for other drivers to cross your path to leave by the next exit and always be on the look-out for their signals.

Don't forget the other rules, we have talked about: mirror - signal - manoeuvre (MSM)  and position - speed - look (PSL). You should apply these routines as much at a roundabout as at any other junction. Remember too, that the signals for left or right turns must be given in good time.