Longer Semi-Trailers Guide

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Benefits and consultation

• Economic benefits

  • 1 in 12 (8.2%) journeys saved on average.    
  • 30 standard pellets can be transported as opposed to 26.  
  • Savings on fuel, labour and maintenance costs.  
  • There is no need for significant technological or infrastructure development.   
  • Saved 78-86 million vehicle kilometres throughout the trial.  
  • The trail provided a net economic benefit of £1,177 million  
  • 1.4 billion is the estimated total cost benefit to businesses and government over 20 years.   

• Societal and environmental benefits

  • Up to a 14% emissions reduction, 8% on average (CO2 savings of 70,000 tonnes through the trail).   
  • Involved in 61% fewer personal injury collisions.   
  • Reduced congestion and associated costs.   
  • Reduced local air pollution.   

• Safety concerns

  At the end of the trial, a public consultation took place om the LST trial in 2021, and below are the key considerations from it:   

   63% of respondents expressed safety concerns related to LSTs.  

  • The primary worry was increased safety risks for vulnerable road users.  
  • Many respondents suggested restricting LSTs to the strategic road network.  
  • Emphasis on keeping them off minor roads and out of towns and cities.  

• Mitigation Measures

   Proposed controls to mitigate casualty risks. 

  • Steering axle design requirements to reduce tail-swing or kick-out.  
  • Operating standards, including licensing, qualifications, and driver training.  
  • Controlled trial conditions replicating route assessment conditions from the LST trial.  

What you need to do to use LSTs

• Notification 

  Before an LST is used on the road, operators must notify the Secretary of State for Transport via electronic communication specifying the name and address of the operator as well as the number of any license held by the operator in respect of LST under section 2 of the Goods Vehicles (Licensing of Operators) Act 1995. This form of notification will remain a legal requirement until 1 June 2028.

  • If an operator’s license is held, it must be completed through the existing Vehicle Operator Licencing System (VOL)
  • If an operator of an LST does not have an operator licence, the DVSA can be notified by. 

  If operating in Northern Ireland, an LST authorised as above for use in Great Britain would also require advance authorisation from the Department for Infrastructure in Northern Ireland. You can contact The Department for Infrastructure via email at vehicle.standards@infrastructure-ni.gov.uk

  Please note, that there is an exemption for LSTs  in an operator’s lawful possession for less than one month to cover non-standard uses such as manufacturing/sales, transfer of ownership and specific maintenance and testing purposes.

  If you use an LST, it must meet the requirements of the LST order. If the LST does not meet those requirements, it may be a breach of the Road Traffic Act 1988.

• Standard regulations

  LSTs must  comply with all regulations that  apply to standard semi-trailer use except for regulations relating to the length or provisions relating to turning circles. These regulations include:

  • The road vehicles (construction and use) regulations 1986.
  • The road vehicles (authorised weight) regulations 1998.
  • The road vehicles lighting regulations 1989.

  LSTs must pass the turning circle test applied to the existing 13.6 meter trailers, for which the LSTs require a steered rear axle. Within the Road Vehicles (Construction and Use) regulations, turning circle requirements for semi-trailers can be demonstrated by:

  • Carrying out a physical test or equivalent method to meet the actual requirements.
  • A calculation utilising only the effective wheelbase between the king pin and the centre point of the trailer’s fixed axles. Please note a calculation that uses the wheelbase between the kingpin and centre point of the fixed axles does not consider how the steering axles may influence the path the trailer follows. Extra reliance on the operation of steering axles for LSTs to comply with turning circle requirements means this primary calculation method cannot be relied on.

• Copies of route planning and risk assessment  

  Operators are legally required to keep copies of route plans and risk assessments for a route for two years beyond the date the LST was used. There is no specific format that these must follow. However, operators will need to demonstrate route planning, risk assessment, and feedback processes proportionate to the scale of the operation and the number of drivers and routes involved.

  The LST order requires that a copy of the route plan and risk assessment must be:

  • Completed before the journey of an LST starts.
  • Carried in the motor vehicle that tows the LST on that established, specific route.

  As good practice, operators may also wish to retain evidence of the following:

  • Their process for route planning and risk assessment.
  • Evidence that drivers have been informed about this process.
  • Any driver route feedback – and any actions taken as a result.

  A more dynamic approach is expected in certain circumstances (such as general haulage, where routes are confirmed at short notice). You could include a plan for activities and risk assessments conducted by office-based staff during the day before sharing with a driver through a text message, email or a phone call. Both paper and digital documents can be used in the same documentation process, providing flexibility for administrative procedures.

• Route planning

  A route plan must be completed in writing (either digitally or on paper) and include all roads on which the LST will be used, including motorways and motorway junctions (although a generic assessment is sufficient to cover LST operations on motorways in most cases). Each new route to or from a destination needs its own plan, which should contain the following:

  • Routing information (for example, turn-by-turn instructions, a map or pre-loaded sat nav). Multiple route options are assessed and approved for a single destination, with final route choice being made depending on traffic conditions.
  • Hazards identified on the route, and advice on managing the risk (for example, how to approach a particular turn, a location where advice may be to occupy two lanes, places where parked cars are an issue, depots with access issues).
  • The option to give feedback on the suitability of the route for LSTs and any additional hazards encountered that may need adding to the risk assessment.
  • The operator needs to safely use both ‘established routes’ and ‘diversionary routes’ as there will be occasions when an established route becomes unavailable. The operator must reasonably consider a diversionary route to be safe for the vehicle and enable the LST to reach or return to a specified route as soon as reasonably practicable. The government has produced the Diversionary Route Checklist to help outline expectations, and although it is not a legal requirement, this document may be used by operators.

• Risk assessment

  A risk assessment must be in writing (digitally or on paper) and consider all relevant risk factors, including, as a minimum:

  • The width and curvature of the part of the road on which the LST is to be used on the route.
  • The amount of space available at any road junction where the LST is likely to turn as part of the route.
  • There is a likelihood that the presence of other vehicles, pedestrians, horse riders, and cyclists on the route will cause difficulties in maneuvering the
  • Assessment of the risks of personal injury (including injury to any animal) and the risk of damage to any vehicle or other property when using the LST on the route specified on the route plan.
  • In light of the highlighted risks, the route is one on which it would be reasonably safe to use an LST.

• Route compliance monitoring

  LST operators should be able to demonstrate they have a process to check all journeys through risk-assessed routes, and procedures should require drivers to follow only risk-assessed routes.

  Copies of route plans and risk assessments need to be kept for two years,  and an LST operator should be able to show DVSA or a Traffic Commissioner (on request) their:

  • Process for route planning and compliance.
  • Actual routes taken.
  • Risk assessments.
  • Compliance records.

  Compliance checking needs to be fit for purpose for the scale and complexity of the operation and must inform relevant managers about levels of route compliance. If drivers are not complying with the planned route, there should also be a process for and evidence of corrective action.

  An LST operator will be expected to demonstrate that the process can lead to corrective action if required. This means there should be a process for:

  • Monitoring compliance internally.
  • Reporting compliance to a suitably responsible manager.
  • Taking any steps necessary to resolve compliance issues (proportionate to the size of the operation).