About Mirrors
Using Mirrors
Using your mirrors must always be part of a safe and systematic routine — for example, the Mirrors–Signal–Manoeuvre (MSM) routine. You must always be aware of how your actions affect other road users, especially those behind you.
The MSM routine involves interpreting what you see in your mirrors and acting appropriately. Regular, sensible mirror use is a key part of safe driving.
Types & Functions of Mirrors
Modern cars must have at least two mirrors:
-
One interior mirror
-
One offside (driver’s side) exterior mirror
Most vehicles, however, have three mirrors:
-
Interior mirror
-
Nearside (left-hand) exterior mirror
-
Offside (right-hand) exterior mirror
Vans and vehicles with restricted rear visibility must have an exterior mirror on both sides.
The Function of Mirrors
Your mirrors:
-
Show the road behind and to the sides of your vehicle
-
Keep you informed of changing traffic conditions
-
Help you make safe, well-judged decisions about speed, position, and manoeuvres
Mirrors & Defensive Driving
Mirrors are one of the most important tools for defensive driving. Use them regularly to stay aware of what’s happening behind and beside you — but remember:
Don’t just look; act safely and sensibly on what you see.
Types of Mirrors
Flat Mirrors
Most interior mirrors and some exterior ones use flat glass.
-
They give an undistorted view of the road behind.
-
This makes it easier to judge the speed and distance of following traffic accurately.
Convex Mirrors
Many exterior mirrors are slightly curved (convex).
-
They provide a wider field of vision.
-
However, objects appear smaller and further away than they really are, making distance and speed harder to judge.
Some vehicles also use split mirrors, which widen your view even further.
Extended-Arm Mirrors
If you’re towing a caravan or trailer, your rear view may be blocked.
Fit extended-arm mirrors so you can clearly see past the sides of the trailer.
This is a legal requirement when towing wide loads.