Monitoring page for "Noise" in "Prague"

The evaluation of road traffic noise and its impact on the population is based on periodical and one-off measurements. The former conducted at properly selected sites constitute a basis for an overall assessment of the situation, and provide data for calculations and methodologies. The latter represent a flexible and ready method of acquiring data needed to address local problems.

Today’s assessment methods are very good and yield relatively accurate results which can substitute in some cases noise level measurements. With some modifications of input data preparations or methodological procedures the methods are capable to assess changes of traffic, road surface, etc.

The periodical noise measurements conducted in the territory of Prague can be divided into the following categories:

a) Road traffic noise maps
b) Noise load distribution maps

c) Regular noise monitoring has been going on since 1984 on eight monitoring sites in Prague. The 24-hour cycle measurements are conducted once in every 1 to 3 months. The eight sites are divided into four pairs, each pair consisting of a site where traffic noise measurements are taken (located close to a road or a street) and a site used to measure background noise levels.

d) Monitoring of ambient noise impacts on human health

In the framework of the “Monitoring of human health in relation to the environment” programme, which is taking place in 21 cities and towns across the country, noise level measurements are conducted in paired sites (noisy x silent) in two-year cycles (1994 - 1995, 1996 - 1997), as well as questionnaire polls concentrating on human health. The programme is implemented by the National Institute of Public Health, the measurement are carried out by the Public Health Office of Prague on three sites in Prague.

e) Irregular measurements

Apart from systematic measurements there are irregular measurements of noise levels conducted in Prague as well, their main purpose being to assess potential noise level impacts of specific civil engineering projects. The scope of the measurements depends on a number of factors, eg. project site/location, building procedure used (building noise), distance from protected buildings and facilities, etc.
Last year, for example, measurements checking and verifying the efficiency of a noise-abatement barrier along D1 Highway near Chodov and renovated noise-reducing barriers in Prumyslová street, Hostivar district. Furthermore, repeated noise monitoring measurements were conducted at the northern and southern entrances of the Strahov Tunnel (measurements from 1995).

f) Other noise measurements

In Prague attention is also being paid to other noise sources such as air conditioning or refrigeration units, industrial plants, boiler rooms, discotheques, and, last but not least, promotional or athletic events held in public places.
It is particularly the first district of Prague which frequently hosts various outdoors promotional, athletic, or cultural events (as a rule, they take place in either Old Town Square or Wenceslas Square). The District Office of Prague 1 arranges noise monitoring measurements of such events.

Model calculations and preparations of the Traffic-Generated Area Noise Map for the Prague 2

Until recently, automotive traffic noise maps (HMAD) were based on noise measurements conducted in a grid of measuring points to which established L_Aeq values were related. An appropriate selection of measuring points allowed an assessment of homogeneous road sections. In the territory of the second district of Prague a possibility of constructing an area noise (two-dimensional) map using mathematical methods has been verified.

The core information used by the mathematical method in question is existing territorial and automotive traffic data contained in the GIS system. After supplementing additional data (road surface types, facade noise absorption coefficients, height of buildings, height of hedges and trees, location and height of walls) and following a necessary transformation of the data from the GIS environment to the HLUK+ (NOISE+) program, L_Aeq values were calculated for the whole territory of Prague overlaid with a regular grid of points. An updated version of the HLUK+ software in the “HLUK+MAPA” (NOISE + MAP) setup was used. The results were subsequently exported to the GIS system which produced ultimate map outputs.

Outputs of the study confirm it is possible to produce a traffic-generated area noise map of Prague (for both daytime and nighttime periods) based on a mathematical formula.

Understandably, the extent of available input data (e.g. the degree of detail of the traffic data network) is a limiting factor when preparing calculation-based maps. A promising solution seems to be a combination of simulation and mathematical methods on the one hand, and supplementary noise measurements on the other hand, so that updated input information can be quickly presented in traffic-generated noise maps for large areas.

Traffic-Generated Area Noise Map of Prague 2

There is also information related to this issue in the following sections of the report
	Health Transport Population Laws, policies, institutions Information