Transport for London (TfL) has finally agreed the star ratings applied to Euro 6 trucks for its Direct Vision Standard (DVS), which is being proposed for introduction in 2019 to assess and rate how much an HGV driver can see directly from their cab in relation to other road users.

But operators will have to contact the makers of the vehicles on their fleet to uncover what the ratings will be for the trucks they run.

Using a star system, the DVS rates HGVs from 0 (lowest) to 5 (highest) based on how much a driver can see directly through their cab windows, as opposed to indirectly through cameras or mirrors.

The most dangerous ‘zero rated’ trucks will be banned from entry into Greater London by 2020.

Each HGV is given a rating based on how much a driver can see of the area of greatest risk to vulnerable road users. This area has been identified through analysis of collision data and through considering how much of a person can, and needs to be seen to avoid a collision.

The area of greatest risk is split into different zones: the zones where most collisions happen are important for the driver to see because they can take action to avoid a collision. These zones are given a higher weighting.

A defined technical measurement is used to calculate the total volume of the area of greatest risk that can be seen directly by the driver and each vehicle is awarded a score. The score determines the star rating which rewards improvements to direct vision.

The higher the star rating, the more a driver can see directly of the area of greatest risk.

Operators are being told to contact truck manufacturers directly to request a DVS star rating for their existing Euro 6 vehicles or to enquire about the rating of a new vehicle. They will need to supply information on their existing truck, which could include the chassis number and age of the vehicle.

The manufacturer will calculate the star rating of the vehicle based on the approved technical protocol. They will then advise its DVS star rating.

TfL said manufacturers are expected to receive a large number of enquiries, but will aim to respond within 10 working days.