Noise assessment

(information from the yearbook Prague Environment 2006)

Overexposure to excessive noise is, similarly as air pollution, the most serious factor affecting health of inhabitants of large cities. Long-term affecting noise nuisance may result in hearing impairments and disorders yet also cause a number of other diseases as stress, neurosis, pathological changes in blood pressure, etc.

Road traffic is the major source of noise in urban environment and especially the heavily growing automobile transport. Exceptions are the vicinities of airports, railways, or even construction sites. Adverse effects of noise are reinforced due to highly concentrated population on relatively small areas. Prague is the worst affected area of the Czech Republic concerning noise affects on inhabitants. Share of population affected by the excessive noise overexposure is closely bellow 50 % (a study of the SZÚ, 1994).

The legally established criterion for environmental noise assessment is the equivalent sound pressure level L_Aeq. It is average energy of momentary sound pressure level values A over a defined period of time which is 1 hour. It is expressed in decibels (dB). Valid legislation on the assessment of acoustic conditions in ambient environment was in 2006 established by the Act No. 258/2000 Code, on public health, in valid wording, and the related Order of the Government of the Czech Republic No. 88/2004 Code, on health protection against adverse effects of noise and vibrations.

The Act No. 258/2000 Code, imposes on every operator and administrator of noise sources the duty not to exceed the highest acceptable noise levels in the environment. If an operator or administrator is not able to fulfil this duty the Act establishes factual requirements and time limits for their further proceeding in the administrative procedure to the authorities of public health protection.

The Order of the Government of the Czech Republic No. 148/2006 Code, which is the executive regulation to the Act, then establishes, inter alia, acceptable values of noise (“limits”) in the environment:

a) uses the term of “old nuisance” and establishes the special limit L_Aeq 72 dB in day-time and 60 dB in night-time for the “old nuisance“; the noise limit value for “old nuisance” is exceeded even though if any of the limit values of L_Aeq for daytime or for night-time is exceeded while uncertainty of the determination must be taken into account as well;

b) imposes on the operators of noise sources (and also on administrators of roads) the duty to provide for compliance with the special limit through the implementation of measures necessary in those places where the limit value has been exceeded; and

c) authorises the competent authority of the public health service to agree temporarily with an exceedance of the limit in those places where compliance with the limit required would take a longer time unless such delay endanger health of inhabitants.

In practise other characteristics of the acoustic conditions are also applied except for the descriptor L_Aeq as the maximum level of acoustic pressure A, L_Amax, (enabling to capture passes of extremely noisy vehicles, for example), minimum level of acoustic pressure A, L_Amin, (for the description of background noise), or potentially probability levels L_An (L_A90 is the most frequently applied one).

The highest acceptable equivalent level of acoustic pressure A in outdoor environment (except for noise generated by air traffic) is determined as a sum of the basic noise level L_Aeq,T = 50 dB and appropriate corrections for daytime or night-time.

Tab. Limit values of environmental noise

Annex No. 3 to the Order of the Government of the Czech Republic No. 148/2006 Code
Corrections for the determination of hygiene noise limit values in protected outdoor environment of structures and in protected outdoor environment

Part A

Type of area protected	Correction (dB)
	1)	2)	3)	4)
Protected outdoor area of structures of medical facilities with accommodation, including spas	–5	0	+5	+15
Protected outdoor area of medical facilities with accommodation, including spas	0	0	+5	+15
Protected outdoor area of other structures and protected other outdoor areas	0	+5	+10	+20

The corrections given in Table cannot be summarised.
For night-time another correction shall be used for the protected outdoor are of structures at the amount of – 10 dB, except for railway noise, for which the correction –5 dB shall be applied.

Explanatory notes to table:
1) This shall be applied on noise from the public production of music, noise from facilities of services and other noise sources, with the exemption of airports, roads, unless they are purpose communication, and furthermore with the exemption of railways unless they are railway stations providing for train assembling works, namely marshalling of cargo trains, train inspection, and carriage repair.
2) This shall be applied on noise from transport on roads except for purpose communications and railways.
3) This shall be applied on noise from transport on main roads on the territory where noise from transport on these roads prevails over noise from transport on other roads. This shall be applied on noise from transport on railways within the protection zone of railway.
4) This shall be applied on noise in the case of the old noise nuisance on roads and railways when the old noise nuisance shall mean the stat of noise level caused by transport on roads and railways, which was created in protected outdoor areas of structures and in protected outdoor areas till 31 December 2000. This correction remains applied even if a new road pavement is laid down, rail top is replaced, or potentially road lanes are widened while maintaining the direction or vertical positioning of the road or railway, in which the existing noise level must not be worsened in the protected outdoor areas of structures and in protected outdoor areas and for short-term bypass routes.
____________
* Section 30 (1) of the Act No. 258/2000 Code.

In the field of legislation on noise the Directive 2002/49/EC on evaluation and control of environmental noise was completely transposed into the Czech legislation in 2006.

The transposition comprises of:

a) Amended Act No. 222/2006 on integrated pollution prevention and control, which amends the Act No. 76/2002 Code on integrated pollution prevention and control, on the Integrated Pollution Register, and amending certain acts in wording of the following regulations, which amended the Act No. 258/2000 Code on public health protection in its valid wording.

The amended Act No. 258/2000 Code on public health protection in its valid wording in Section 81 imposes duties related to the strategic noise mapping on the Ministry of Transport, Ministry of the Environment, Ministry for Regional Development, and regional authorities of the Czech Republic;

b) The Decree of the Ministry of Health of the Czech Republic No. 523/2006 Code of 21 November 2006, establishing limit values of noise indicators, their calculations, fundamental requirements for the content of strategic noise maps and action plans, and conditions for the public involvement in their preparation (the decree of noise mapping);

c) The Decree of the Ministry for Regional Development of the Czech Republic No. 561/2006 Code establishing agglomerations.

Note:
The Ministry of the Environment of the Czech Republic prepares a decree on determining and establishing of silent areas in open landscape.