Since 2012, a trial of longer semi-trailers (LSTs) of up to 15.65 metres has taken place on roads in Great Britain, enabling 30 standard UK pallets to be transported in a trailer as opposed to 26.Sidmouth Herald: Stuart HughesStuart Hughes (Image: Terry Ife)

This has provided more efficiency and fewer lorry journeys for commodities limited by bulk as opposed to weight. This efficiency is further enhanced by a number of operators utilising double deck trailers.
The maximum length of a longer semi-trailer plus tractor unit is 18.55 metres, marginally shorter than road train combinations allowed in general circulation in the UK and mainland Europe. Until agreement is given that LSTs can be used on international operations, they will be limited to use in the UK.

The ongoing LST trial now involves around 2,600 LSTs. Up to the end of 2019 the trial results indicated that:

  • On average, the use of LSTs reduced journey numbers by 1 in 12, with more than 54 million vehicle kilometres saved
  • A total of 48,000 tonnes of CO2(e) and 241 tonnes of NOx have been saved
  • On a per kilometre basis, LSTs have been involved in about 53% fewer personal injury collisions and casualties than the GB articulated heavy goods vehicle (HGV) average.

And now, the consultation asking whether the DfT should end the existing longer semi-trailer trial (LST) ahead of schedule is being carried out and will close on the 1st February 2021.
Although originally planned to run until 2027, DfT believes the trial has reached a point where continuing is unlikely to provide useful results and that remaining issues, relating to the safety, can only be answered outside of trial settings.
By ending the trial, the DfT is seeking to implement one of four options. Apart from the ‘Do nothing’ option (in which case the trial runs until 2027) the other three options will allow any number of extra LSTs onto the roads. These numbers would only be controlled by market forces.
I share Devon County Council traffic engineers’ concerns that the worst case option is ‘Allowing LSTs to enter into general circulation’ which would remove any opportunity to control their use through the Traffic Commissioner and the Operator liability.
The only way to control their inappropriate use on the Devon’s highway network would be via Traffic Regulation Orders which would be totally unachievable and would be a huge burden on the Traffic Authority.
The County Council will therefore be supporting Option 2 Lighter regulatory option which in fact is the DfT’s preferred policy option as it allows the whole of the freight industry to have unrestricted access to LSTs and therefore it makes an important contribution to reducing emission levels.

This option would remove the cap on the total number of LSTs permitted and would allow the market to decide the quantity in operation based on commercial need. To ensure the excellent safety record of LSTs operated under the trial is at least maintained this option proposes that the regulatory measures of, among others:

  • Accident reporting to the department where there is loss of life, injury (on public or private land) or damage (when on a public highway)
  • Operators being required to provide drivers with a minimum of half a day’s training in respect to the particular LST design before a driver operates an LST for the first time.
  • Operators being required to undertake a risk assessment of the proposed route for the LST to ensure it is appropriate
  • Operators being required to retain a record of all risk assessments undertaken prior to LST journeys and make them available to the police, DVSA, OTC or traffic commissioner on request

Finally to put minds at rest, the LST’s, if regulated, would only be able to travel off the trunk road network for 20% of their entire journey. So, it is unlikely they will be used to destinations such as, in my county division, Sidbury (where I have called for a weight restriction) and Sidmouth. But the Exeter industrial sites would be within their reach. The regulated options would allow Devon County Council to control their use on unsuitable roads easily through the Traffic Commissioner and the Operators licence.