Definitions and Categories

When reading any legislation, there are always terms laid out and referred to. These definitions can be confusing as they refer to many aspects of the Construction and Use Regulations (and other legislation) and have wide-ranging application for their use. An example of this is the reference to a Category N3 Goods Motor vehicle i.e. vehicles used for the carriage of goods and having a maximum mass exceeding 12 tonnes or an O4 Trailer (trailers that have a maximum mass exceeding 10 tonnes). 

The following is a general guide to avoid confusion. 

Definitions 

Please find links below relating to the Definitions and Categories applied to Motor Vehicles and Trailers, including:

  • Domestic Legislation 
  • RTA (1988), C&U (1986) and AW Regs (1998) 

Domestic Legislation

The following definitions are contained within current domestic legislation and cover the following:

Goods Vehicle

Means a motor vehicle or trailer constructed or adapted for use for the carriage of goods. This includes goods or burden of any description 

Motor Vehicle

Means a mechanically propelled vehicle intended or adapted for use on roads, and trailer means a vehicle drawn by a motor vehicle 

Motor Car

Means a mechanically propelled vehicle (other than a motorcycle or invalid carriage) which is constructed itself to carry a load or passengers and the unladen weight of which:

  1. If constructed solely for the carriage of passengers and their effects, and is adapted to carry not more than seven passengers exclusive of the driver, does not exceed 3,050kg; 
  2. If constructed or adapted for use for the carriage of goods or burden of any description, does not exceed 3,050kg  
  3. Does not exceed 2,540kg in a case not falling within a or b above 

Heavy Motor Car

Means a mechanically propelled vehicle which is not a motor car, is constructed itself to carry a load or passengers and with an unladen weight exceeding 2,540kg 

Motor Tractor

Means a mechanically propelled vehicle which is not constructed to carry a load, other than excepted articles, with an unladen weight not exceeding 7,370kg 

Locomotive

Means a mechanically propelled vehicle which is not constructed to carry a load, other than excepted articles, with an unladen weight exceeding 7,370kg 

Excepted articles

Water, fuel, accumulators and other equipment used for propulsion, loose tools and loose equipment. 

Centre-axle trailer

Means a trailer having only a single axle or group of axles which is positioned at or close to the centre of gravity so that, when the trailer is uniformly loaded, the static vertical load transmitted to the towing vehicle does not exceed 10 per cent of the maximum authorised weight for the axle or group of axles or 1,000kg, whichever is the less 

Articulated vehicle 

Means a heavy motor car or motor car with a trailer attached so that part of the trailer is superimposed on the drawing vehicle and, when the trailer is uniformly loaded, not less than 20 per cent of the weight of its load is borne by the drawing vehicle. The motive or tractor unit is the vehicle and is a motor car if it weighs up to 3,050kg unladen, and a heavy motor car if it exceeds 3,050kg unladen. 

Unladen weight 

Defined as the weight of the vehicle or trailer inclusive of the body and all parts necessary to, or ordinarily used with, the vehicle on the road. Where alternative bodies or parts are used, the heavier is taken. The weight of water and fuel, loose tools and equipment are not included. 

Road-friendly suspension

Means a suspension system whereby at least 75 per cent of the spring effect is produced by air or other compressible fluid under pressure or suspension recognised as being equivalent within the Community as defined in Annex II of Council Directive 96/53/EC (a). 

 

These definitions are derived from the Road Traffic Act 1988 and the Road Vehicles (Construction and Use) Regulations 1986 and the Road Vehicles (Authorised Weight) Regulations 1998. 

 

Vehicle categories are defined according to the following international classification:

Category M

Motor vehicles with at least four wheels used for the carriage of passengers. 

  • Category M1 - Vehicles used for the carriage of passengers and comprising no more than eight seats in addition to the driver's seat. 
  • Category M2 – Vehicles used for the carriage of passengers, comprising more than eight seats in addition to the driver's seat, and having a maximum mass not exceeding five tonnes. 
  • Category M3 – Vehicles used for the carriage of passengers, comprising more than eight seats in addition to the driver's seat, and having a maximum mass exceeding five tonnes. 

Category N

Motor vehicles with at least four wheels used for the carriage of goods. 

  • Category N1 – Vehicles used for the carriage of goods and having a maximum mass not exceeding 3.5 tonnes. Category N1 Motor vehicles are divided into three classes, depending on their weight when empty:
    • Class I - for vehicles with weight when empty of under 1,205kg 
    • Class II - for vehicles with weight when empty of between 1,205kg and 1,660kg  
    • Class III - for vehicles with weight when empty of over 1,660kg 
  • Category N2 – Vehicles used for the carriage of goods and having a maximum mass exceeding 3.5 tonnes but not exceeding 12 tonnes 
  • Category N3 – Vehicles used for the carriage of goods and having a maximum mass exceeding 12 tonnes 

Category O

Trailers (including semi-trailers) 

  • Category O1 – Trailers with a maximum mass not exceeding 0.75 tonnes. The year of manufacture must be marked on O1 trailers manufactured from 1 January 1997 
  • Category O2 – Trailers with a maximum mass exceeding 0.75 tonnes but not exceeding 3.5 tonnes 
  • Category O3 – Trailers with a maximum mass exceeding 3.5 tonnes but not exceeding 10 tonnes 
  • Category O4 – Trailers with a maximum mass exceeding 10 tonnes 

The following links provide guidance and further information 

The Road Vehicles (Authorised Weight) Regulations 1998 
https://www.legislation.gov.uk/uksi/1998/3111/contents/made 

Road Traffic Act 1988 
https://www.legislation.gov.uk/ukpga/1988/52/contents 

The Road Vehicles (Construction and Use) Regulations 1986 
https://www.legislation.gov.uk/uksi/1986/1078/contents/made