Mirrors
Using the mirrors has to be part of a safe, systematic routine such as Mirrors – Signal – Manoeuvre (MSM). You must always know how your driving is likely to affect traffic behind you.
The MSM routine includes interpreting what you see in the mirrors and acting appropriately. Regular and sensible use of the mirrors is an essential element of safe driving.
Modern cars are required to have an offside (driver’s side) mirror fitted, as well as an interior mirror. However, most vehicles have three driving mirrors
- an interior mirror
- two exterior mirrors: one on the nearside (left-hand) door and one on the offside (right-hand) door.
Vans and other vehicles with a restricted view to the rear must have an exterior mirror on each side.
Function
Your mirrors
- give you a view of the road behind and to the sides
- enable you to keep up to date with what’s happening behind and to the sides of your vehicle
- help you to make safe and sensible decisions, based on the position and speed of other traffic.
Defensive driving
Mirrors are one of the keys to defensive driving. Always use them to keep up to date with what’s behind and to the sides of your vehicle.
Flat mirrors
Most interior and some exterior door mirrors have flat glass.
Flat mirrors don’t distort the picture of the road behind. This makes it easier to judge the speed and distance of traffic behind you.
Convex mirrors
Many exterior mirrors have convex glass, which
- is slightly curved
- gives a wider field of vision.
This makes accurate judgement of speed and position of vehicles behind you more difficult.
A vehicle behind seems smaller in a convex mirror, so it could be closer than you think.
Some cars have ‘split’ mirrors, which give a wider field of view.
Extended-arm mirrors
Some caravans and trailers block your interior mirror’s view of the road behind, which means you must rely on your exterior mirrors.
If you’re towing a caravan or a wide trailer, fit side mirrors with extended arms to enable you to see past the caravan or trailer.