What are UK Legal Requirements for trailers?

Trailer Lighting is an often neglected aspect of a vehicle and frequently not sufficiently lit up causing a danger on the roads and not meeting legal requirements. It's often the case that a a trailer will obscure the tractors lighting while not providing any of it's own meaning that people might not see brake lights, reverse lights, or might not see the trailer altogether in darkness.

This blog is aimed to help clarify exactly what is required and indeed necessary for safe and legal travel while towing a trailer. All lighting products featured are required to be E marked to be acceptable in UK law, all our lighting products on our website are E marked. As a disclaimer, this guide is not comprehensive and is only a summary of the DVSAs guidelines that can be found here: https://assets.publishing.service.gov.uk/media/6568bc212ee693001360cbc0/individual-vehicle-approval-inspection-manual-trailers.pdf

Reflectors:  While being the easiest thing to fit to a trailer, it's often the least well known. Under UK law, you need at least 2 triangular red reflectors on the rear of the trailer. Their purpose is to act as a back-up of illumination should the electronic lighting fail. They must be between 900-250mm from the ground (there are couple of exceptions to this), and 400mm from the sides or 600mm if the width of the trailer is less than 1300mm. You also need front and side reflectors (white and amber respectively) but these should be non triangular. They have the same height requirements but only the front reflectors have the same width requirements. You may need more than one side reflector on each side if the trailer is longer than 1m. 

Other reflectors such as conspicuity tape and marker boards may help the visibility of the vehicle but are optional. Bear in mind that if you do use them, you have to comply to DVSA standards.

Marker Lights: Marker lights are intended to 'mark' the position and size of the vehicle meaning that in low light conditions, a road user can easily see how big the vehicle/trailer is and importantly, which way is it is facing. UK law determines that trailers must have the correct number of marker lights on it and that they must be the correct colour (to indicate whether you're looking at the back, side or front of the vehicle). You must have only red markers at the back, amber markers on the sides and white markers at the front the same as with reflectors. Many modern marker lights (including our range) have reflectors built in, eliminating the need for separate components. 

         - Indicators. UK law also requires that you have flashing indicator lamps along the side of the vehicle to indicate that the vehicle intends to turn in that direction. However, you can work around this by installing a flasher unit that will cause the marker lights to flashing like an indicator and fulfilling both roles. Alternatively, some marker lights have this indicator function built in and once wired up, will produce the same effect.

         - Stalk Outline Marker Lamps: All trailers over 2.1m wide must also have 'End-Outline Marker Lamps' or as they're more commonly known, 'stalk lamps' because they frequently stick out to the sides on so-called stalks. They're purpose is an extension of the purpose of the marker light which is to mark out the very extremities of the width of the vehicle. They should be fitted as far to the sides as possible on the vehicle and certainly not 400mm from the edge. In most cases they are made of rubber to make them flexible since colliding with stationary objects is commonplace and it prevents damage to both the object it hits and the lamp/trailer itself. They are required to present a white light to the front and a red light to the rear but most have an amber light to the sides also. They must be visible from both the front and rear of the trailer hence the need to stick out the sides.

Number plate lights: You must also illuminate your number plate with 1 or 2 number plate lights that should come with the marker lights without needing any further switch or button. They must be white in colour and be bright enough to fully illuminate your number plate. 

Rear Fog Light: Back in the olden days, vehicles tail lights were so dim that they were a hazard to road users especially during foggy weather and they often couldn't see vehicles ahead and so would crash into them from behind. And so a regulation was passed that required all trailers and many other vehicles to have front and rear fog lights fitted so that the driver could turn them both on with one switch if there was poor visibility. These days, lighting has become far brighter than before making the rear fog light mostly redundant. However it is still law to have at least 1 but a maximum of 2 fitted to the back of the trailer (2 are required if the trailer is over 6m long). Many modern combination or 'cluster' lamps have these in built but not all, so be careful.

Reverse Light: Reverse Lights should come on when the driver goes into reverse gear to warn people behind you that you're not travelling in the direction they would expect. DVSA requirements are the same as rear fog lights in that you need 1 or 2 fitted depending on how long the trailer is. 6m or longer and you need 2 but no more. They must be fitted between 250mm and 1200mm from the ground.

Brake/Stop Lights: It may go without saying but you need brake lights on your trailer since the tractors brake lights are probably concealed. You need at least 2 of them lower than 1.5m from the ground or 2.1m if the structure of the trailer makes that impossible. They should also be at least 600mm apart or 400mm if the trailer is less than 1.3m wide. Many brake/stop lights are integrated into the tail lights which is another trend that developed from older technologies: frequently with bulb rear lights, the brake light and tail lights will be operated on the same bulb but with seperate filaments to produce different levels of brightness.

If you're looking for your own lighting solutions then check out our range of combination rear lights, marker lights and others here: https://shop.universalelectrix.co.uk/pages/vehicle-lighting