The operation of buses with a maximum permissible mass of more than 5 tons is prohibited if:

Explanation

In both cases; both the absence of wheel chocks and the fitting of red reversing lamps at the rear.

A bus with a permissible maximum mass over 5 tonnes must carry wheel chocks, and their absence prohibits operation. The reason is simple physics: several tonnes of mass on a slope generate a force that the parking brake alone was not designed to hold for long periods, especially when the vehicle is stopped on a gradient for a wheel change or repair and one axle may be lifted off the ground. A wheel chock is a mechanical restraint that depends on no system at all and is in everyday use on Armenia's mountain roads.

A red reversing lamp is independently an offence too, because it breaks two rules at once: a reversing lamp must give white light, and red at the rear has a completely different meaning. The driver behind equates the red light with a brake or tail light and does not realise that the vehicle in front is reversing towards him. In a car park or at a stop, that misunderstanding leads to an impact, and with a pedestrian present, to injury.

Worth memorising: the reversing lamp and the number-plate lamp are the only white lights permitted at the rear of a vehicle; changing their colour is just as much an offence as fitting an unauthorised white light at the rear.

• The absence of wheel chocks on a bus over 5 tonnes really does prevent operation, but it is an incomplete answer and sets aside the reversing lamp colour fault. • A red reversing lamp is an offence on its own too, but the absence of wheel chocks is raised alongside it and you must accept both.

Sources and content coverage · Report a content error