Environmental noise protection

Environmental pollution with noise is a significant burden in all developed countries, as a result of a plethora of sources in urbanised areas and ever more frequently in natural environments. Settlements are particularly affected as the pollution causes a reduction in health to residents, is detrimental to their state of being, diminishes the value of their real estates, thus noise can be characterised as a general vice to society. In nature noise alters the acoustic landscape and animal habitats. On a European level, environmental  noise protection is regulated by directive 2002/49/EC. The directive sets definitions for noise indicators and computational methods for their estimation, specifies key noise sources (roads, railways, air

Noise is present everywhere

ports, industry), and acknowledges a responsibility of informing the public about noise pollution data, potential detriments to health, and the necessity of environmental reports and mitigation measures. The benchmarks for environmental noise pollution are values of noise indicators, expressed in dB(A). The indicators are as follows:

  • ‘Lday’, day-noise indicator (between 6.00 a.m. and 6.00 p.m.)
  • ‘Levening’, evening-noise indicator (between 6.00 p.m. and 10.00 p.m.)
  • ‘Lnight’, night-time noise indicator (between 10.00 p.m. and 6.00 a.m.)
  • ‘Lden’, day-evening-night noise indicator (weighted mean of the prior three indicators).
Typical noise levels

 In special cases the degree of noise pollution can be estimated with alternative indicators such as, noise peaks, low-frequency noise exposure etc. The degree of pollution is determined by a combination of measurements and computational models. The legislation defines upper limit values for the aforementioned noise indicators (maximum permissible noise levels), that a source can cause. Limit values vary according to overall pollution and type of source (railway or road transport, industrial equipment or facilities). If the limit values are exceeded the manager of the source is responsible to ensure further measures are put in place to reduce emissions or limit their leakage into the environment. The value of indicators is determined either by direct measurements at location or computational models that take into account the noise emission characteristics of the source and the acoustic topology of the emission surroundings. 

In addition, limit values are also correlated with the vulnerability of the vicinity. The vulnerability is determined by land use that is in turn defined by the respective municipality spatial planning acts.