Weights, Dimensions and Loads
This domain covers the legal size and mass limits for buses and coaches, how loads must be distributed and secured, and the practical arithmetic a driver does before departure. Expect questions that give you a vehicle, a passenger number and a luggage weight and ask whether it may move.
Dimensions
- Maximum width: 2.55 m; 2.60 m for refrigerated vehicles with insulated walls.
- Maximum height: 4.00 m, load included.
- Maximum length: 12 m for a rigid bus, 18 m for an articulated bus, 18.75 m for a bus-and-trailer combination.
Weights
- Two-axle bus: 18 t maximum gross weight.
- Three-axle bus: 25 t.
- Articulated bus: 28 t.
- Single axle: 10 t; the driven axle of a bus is commonly allowed 11.5 t. These are ceilings, not targets: the manufacturer's plate and the axle limits can be lower and always prevail.
Loads
Luggage goes in the holds, secured so that it cannot shift in braking. Weight must be spread so that no axle is overloaded - a full rear hold and an empty front hold can push the drive axle over its limit even when gross weight is legal. Doors and emergency exits must stay clear. Nothing may obscure lights, the registration plate or the driver's view, and any projection must be marked. Roof racks, where fitted, must stay within the 4.00 m height and within the roof load rating.
Worked example
A three-axle coach has an unladen mass of 16.2 t. It carries 55 passengers at 80 kg including hand luggage (4.4 t), 4.5 t of luggage in the holds and 0.3 t of water and fuel. Total = 16.2 + 4.4 + 4.5 + 0.3 = 25.4 t against a 25 t limit. The vehicle may not depart: reduce luggage, move passengers, or split the load across two vehicles. Note the answer would be the same even if gross weight were 24.9 t but the drive axle alone exceeded 11.5 t.
Traps
- Confusing 4.00 m height with 4.00 m width or the 2.55 m width limit.
- Checking only gross weight and ignoring individual axle loads.