An AIL (Abnormal Indivisible Load) is any load that cannot be broken down into smaller loads for transport without undue expense or risk of damage, an example of such a load would be a 180 tonne transformer. Whereas an articlulated vehicle carrying a normal load can reduce the weight of the load by removing part of it and redistributing the remainder, this is not the case of an AIL.
An AIL is also any load that exceeds certain parameters for weight, length, and width, wherupon the vehicle carrying the load would not comply with Construction and Use Regulations due to the weight of the load exceeding 44,000 kgs; or as a result of the width and/or length of the load dictating that it can only be carried on a heavy motor car, trailer or combination of both where the same would not comply with the Construction and Use Regulations in all respects.
AIL's are a complex subject due to the regulations that affect them. This section merely gives a brief insight into AIL's and there carraige.
Special Types Rules
The Special Types rules permit:
- abnormal indivisible loads to be carried which exceed the weight and/or dimensions limits contained in the Road Vehicles (Construction and Use) Regulations 1986, the Road Vehicles (Authorised Weight) Regulations 1998; and in cases where
- a variety of unusual vehicles, such as items of engineering plant or military vehicles, whose design and function prevents compliance with construction and use regulations, to be used on public roads in certain circumstances.
These rules are contained in section 44 of the Road Traffic Act 1988 and the Motor Vehicles (Authorisation of Special Types) General Order
2003 (STGO). Only AIL's may be carried under these rules. Information pertaining to section 44 can be found on the
Section 44 page within this section.
Rules governing Weights and Dimensions are to be found in section 41 of the Road Traffic Act 1988.
Vehicle Categories and Weights
Vehicles are classified into three groups according to total laden weight. Current categories are set out below with their related axle weights and spacings. A vehicle can be used in any category provided it meets all the conditions of that category. An empty vehicle can travel in a different category when unladen.
The maximum gross weights for the three categories are:
|Category||Maximum GVW (kg)||
|Maximum Axle Weight|
D x 7,500
D x 12,500
In the table above, D is the distance (measured in metres) between:
- the foremost axle and the rearmost axle of the vehicle carrying the load;
- in the case of an articulated vehicle, the kingpin and the rearmost axle on the semi trailer; or
- in the case of any other description of combination, the foremost axle and the rear most axle of the group comprising all those vehicles in the combination that are carrying a load
Category 1 vehicles or combinations must have, at least, six axles. However Category 1 articulated vehicles up to 46,000 kgs may have five axles.
Indivisible loads which are abnormal only in respect of their dimensions and not their weight may be able to be carried on standard vehicles subject to the construction and use regulations. However, it must be noted here that loads wider than 4.3 metres cannot be carried under Construction and Use Regulations and all movements where a load wider than 4.3 metres must comply with STGO rules.