An SPB measurement accurately determines the sound properties of road surfaces. The results of an SPB measurement are directly comparable with the measurements of other reference road surfaces. It is the method for determining the noise reducing effects of road surfaces.
Road surface correction
The implementation of the SPB method is specified in ISO 11819-1. The noise emitted from light, medium-weight and heavy motor vehicles is measured at defined distances from the road. The Dutch classification system for the acoustic properties of road surfaces (road surface correction, “Cwegdek”) is based on the results from hundreds of SPB measurements. SPB measurements are also required to determine the road surface correction of new road surfaces.
Although the SPB method is extremely reliable and representative, it does require a great deal of expertise on the part of the operator. The traffic being measured must be driving past at a constant speed and with sufficient distance between vehicles to measure the passage of individual vehicles. The surrounding environment must also be guaranteed free from unwanted reflections and noise interference. Because of our many years of experience and our professional measuring team, M+P is known internationally for its outstanding expertise in conducting SPB measurements. Every year we perform several hundred road surface measurements. The same method of measurement is also used to measure the noise from the expansion joints of bridges.