In the Netherlands there is a primary need for reliable, objective data about environmental noise pollution. Geluidsnet (translated: Soundnet) was founded in 2003 to meet this need, and is now a growing company specialising in accurate, long-term measurement of environmental background noise and effective communication of results to the client. Using a large network of noise meters, Geluidsnet can give definitive and traceable information about sound levels and patterns in key areas over the whole country.

Noise pollution from aircraft is a particularly big issue in the Netherlands, and Geluidsnet is a front-runner in identification of aircraft-generated noise. Novel analysis algorithms developed in-house mean that Geluidsnet is able accurately to report the number and frequency of aircraft passes in spite of high levels of other background noise.

Geluidsnet’s data has on several occasions formed the basis for government policymaking, and is otherwise used by its clients for a variety of private and public information purposes. The company operates in a fully transparent and verifiable manner, and has a diverse customer base, from interest groups and householders to research organisations and government bodies.
 

Novel approach to measurement
Geluidsnet has installed a large number of strategically placed unmanned noise meters which continuously transmit their measurements to a central database using internet connections. The meters themselves are compact, low-cost and low-maintenance, and can be positioned in almost any location at ground or roof level. They operate continuously, transmitting their results over the internet to a central database. Geluidsnet is thus not limited by the high cost of manpower or equipment, in contrast to more traditional methodologies.

Easy access for the customer
The internet is used both to collect incoming data and also to display results to the customer. Real-time and historic measurements from all meters are constantly available to clients through the Geluidsnet website, and further subscription services are available such as regular reports from specific locations.

High quality data
The large number of sampling points (nearly fifty at the start of 2007, to increase to over one hundred by the end of the year) generates a reliable picture of sound over large areas. It also means that if measurements at one location are disrupted, data are still available from others nearby.

Geluidsnet has rigorous quality control procedures in place, so that irregularities are automatically traced and correlated against other information from that and neighbouring meters in order to check whether the fluctuation is real. Furthermore, as data can be sampled over periods from several days to several years, long-term trends in noise levels can be distinguished from periodic variations over short timeframes.