The dimensioning of the cold end of the emission control system is determined primarily by the acoustical requirements and backpressure requirements. It is to this end that pipe diameters and silencer volumes, shapes, internal designs and locations within the total emission control system are rightsized and customised for each engine/vehicle combination.

The challenge lies in always finding the most effective solution within the constraints of compactness, weight and cost, while accounting for the aspects of durability, feasibility, design robustness and standardisation. BOSAL is constantly developing new acoustic solutions and state-of-the-art components aimed at facilitating this process.