REGULATIONS AND REQUIREMENTS

Make sure your trailer has adequate lighting, as this is a legal requirement. This simple guide will help you comply with current laws for use on the public highway in the United Kingdom.

Trailers must be fitted with:

Two red rear position lamps.
Two red stop lamps.
Two red triangular reflectors.
An illuminated number plate.
Front white reflectors.
Amber direction indicators (designed to flash between 60 and 120 times per minute).
Some means of informing the driver that the trailer’s indicators are working correctly, such as a buzzer or a tell-tale lamp.

If the trailer is more than 1.3 m wide, it must also have:

At least one red rear fog lamp.

Larger trailers (1.6 m and above) require additional features:

Front white reflectors.
Front white marker lamps/lights.

Trailers manufactured from October 2012 that are equipped with brakes require an additional feature:

A reversing lamp.

Longer trailers (6 m and above, excluding the drawbar and excluding boat trailers) require additional features:

Red/white side markers.

Placement of lamps and reflectors

Indicators must be a minimum of 350 mm and a maximum of 1500 mm above the ground.
Indicators must be no more than 400 mm from the trailer’s outer side.
Indicators must be at least 400 mm apart.
Rear triangular reflectors must be positioned a minimum of 250 mm and a maximum of 900 mm above the ground, at least 600 mm apart, and no more than 400 mm from the sides.
A single rear fog lamp must be mounted anywhere between the centreline and the outer edge of the trailer.
If two rear fog lamps are fitted, they must be separated and placed on opposite sides at the rear of the trailer.
Rear fog lamps must be a minimum of 250 mm and a maximum of 1000 mm above the ground.
Rear fog lamps must be at least 400 mm apart.
There must be at least 100 mm clearance between rear fog lamps and rear lamps/indicators.

Lighting installation – All trailers

The trailer must be equipped with lamps or retro-reflective material that show only a white light at the front, except for:

An amber light from a direction indicator.
An amber light from a hazard warning lamp.
A yellow light from visible conspicuity (marking) material.
An amber light from a side marker lamp.

Rear lamps must emit only red light; front lamps must emit only white light.

The operation of any lamp must not affect any other lamp, nor be affected by any other lamp, unless specifically designed to do so. Lamps must not move by swivelling, deflecting or otherwise while the trailer is in motion, except for a work lamp used to illuminate a work area or the scene of an accident, breakdown or road works in the vicinity of the trailer on which it is fitted.

All mandatory and optional rear lamps, reflectors and markers must be installed in their correct orientation.

When any door or other moving part is held in an open position (any position in which the component remains, with or without fixed support), the following — front and rear position lamps, front and rear indicators, and rear retro-reflectors — must meet one of the following conditions:
a) At least 50% of the apparent surface of the lamp or reflector is directly visible in front of/behind the trailer, as applicable; or
b) Additional lamps/reflectors that are fully visible and meet all the requirements for the above lamps/reflectors are switched on/visible; or
c) A notice on the trailer informs the user that, in certain positions of the moving components, other road users must be warned of the trailer’s presence on the road (for example, by placing a warning triangle).

Figure 1: Horizontal angles of visibility

Each lamp and reflector must be positioned to provide an “apparent surface”. At least 50% of the apparent surface of each lamp or reflector must be visible from any point within the relevant angles.

Horizontal angles of visibility

Figure 2: Vertical angles of visibility

Front position lamps, retro-reflectors and indicators (including side repeaters):
‘A’ = less than 750 mm above ground level.
‘B’ = 750 mm or more above ground level.
‘Ar’ = Front retro-reflector less than 750 mm above ground level.
‘Br’ = Front retro-reflector 750 mm or more above ground level.
‘C’ = Rear position lamps and stop lamps 1500 mm or more above ground level. Indicators and rear reflectors 750 mm or more above ground level.
‘D’ = Rear position lamps and stop lamps less than 1500 mm above ground level.
‘E’ = Rear position lamps, stop lamps, indicators and rear reflectors less than 750 mm above ground level.
‘F’ = Rear fog lamps.

Figure 3: “Rearward” of the trailer

“Rearward” of the trailer means an area whose sides are at an angle of 15 degrees outwards from the outermost edge of the trailer (starting at the rear corner) and extending up to 25 m from the rear of the trailer (measured along the trailer’s longitudinal axis).

Retro-reflectors

All reflectors must be marked with ‘e’ or ‘E’ and, where applicable, other approval marks.
Rear reflectors must be oriented predominantly to the rear.

Conspicuity markings; trailers over 3500 kg

Conspicuity markings must only be applied to the correct trailer category (see application).
All conspicuity material must be of an approved type.
There must be at least one visible approval mark on one element of retro-reflective conspicuity material installed on each side of the vehicle.
The maximum gap between adjacent elements must not exceed 50% of the width of the smaller adjacent element (see note 5).
The lowest edge must be between 250 mm and 1500 mm above the ground.
The minimum width of the markings must be at least 50 mm.
The maximum width of the markings must not exceed 60 mm.

Rear conspicuity markings; trailers over 3500 kg and more than 2.1 m wide

Must be red or yellow.
Must cover at least 70% of the total width of the trailer.
Must be at least 200 mm away from any mandatory stop lamp.

Side conspicuity markings; trailers over 3500 kg and more than 6 m long

Must be white or yellow.
Must extend to within 600 mm of each end of the trailer (see Figure 2).
Must cover at least 70% of the total length of the trailer (see note 8 and Figure 5).
If full or partial contour markings are applied, the maximum height should be as close as possible to the top of the body (see Figure 2).

End-outline marker lamps, position (side) lamps, stop lamps and side marker lamps

All lamps must be marked with ‘e’ or ‘E’ and, where applicable, other approval marks.

Front and rear position lamps

The correct colour must be fitted to the trailer (Table 1).
They must operate.
They must emit white light at the front / red light at the rear only.

Stop lamps

The correct colour must be fitted to the trailer (Table 1).
They must operate.
They must emit red light only.
They must illuminate only when the service brake is applied, and must extinguish when the service brake is released.

Side marker lamps

The correct number must be fitted to the trailer (in accordance with positional requirements).
They must operate.
They must emit amber light (red is permitted if within 1 metre of the rear).

End-outline marker lamps

(Requirements as per approval markings and colour in Table 1.)

Direction indicators

All lamps must be marked with ‘e’ or ‘E’ and, where applicable, other approval marks.
They must operate.
The correct colour must be fitted to the trailer (Table 1).
They must flash at a rate between 60 and 120 times per minute (with all mandatory indicators operating and the towing vehicle’s engine running if the rate would otherwise fall below the requirement).
All indicator lamps must emit amber light.
The hazard warning device must operate all direction indicators simultaneously.

Trailer types

Pig trailer
A trailer that has an axle group near the centre of the length of its load-carrying surface.

Dog trailer
A trailer with two axle groups, of which the front axle group is steered by connection to the drawing vehicle.

Semi-trailer
A trailer that has an axle group towards the rear end of the length of its load-carrying surface such that a significant load is imposed on the drawing vehicle, or part of the load-carrying surface is over the towing vehicle.

Caravan
An enclosed trailer designed to be used as a mobile home or dwelling when parked. It will typically provide fixed sleeping accommodation and/or facilities for food preparation.
A trailer permanently fitted with a folding/popup roof (such as a camper trailer) is a caravan. Enclosed trailers built to accommodate people when parked—such as worker welfare units, mobile kitchens or mobile offices—are also considered caravans.

Box trailer
A general-purpose trailer with a load space bounded by vertical sides. This category includes a box trailer fitted with a cover but not equipped as a caravan, e.g. only fitted with temporary sleeping accommodation.

Tray-body (flatbed) trailer
A general-purpose trailer with a flat load platform not bounded by vertical sides.

Boat trailer
A trailer built specifically to carry a boat.

Car trailer
A trailer built specifically to carry a motor vehicle, such as a passenger car or a race car.

Horse float (horsebox)
A trailer built to carry one or more horses or similar livestock.

Plant trailer
A trailer that, instead of a load space, has machinery attached to it, such as an air compressor, concrete mixer or drilling rig.

Grouping of rear lamps

Rear position (side) lamps, stop lamps, direction indicators, number-plate lamps and retro-reflectors may be grouped in the same units, provided their individual requirements are met.

The following are examples of acceptable arrangements