The limit values of noise indicators are defined by the Decree on the levels of noise in the environment. They vary by the vulnerability of the relevant space (areas protected from noise), time of the day (day, evening, night, day-evening-night period), and the type of source (traffic, machinery or facilities, total burden). The Decree defines four types of noise protection areas:
- areas protected by environmental protection legislation,
- areas specific for housing and tourism, hospitals and health resorts, and quiet areas in agglomeration protected by special municipal law,
- general areas with housing, educational, sport purposes and other areas with buildings with protected spaces,
- areas for non residential use and other buildings with protected spaces such as production facilities, transport infrastructure, farmland, forests, and defense facilities.
The basis for determining these areas is the purpose of space in the detailed spatial plan of the competent municipality. The competent municipality can independently determine III. and IV. areas, while II. areas can be determined on the basis of an expert groundwork and on the initiative of the municipality only by the minister with environmental jurisdiction .
Special considerations are delegated to quiet outdoor areas and quiet areas in agglomerations. A quiet outdoor area is catalogued as a type 1. area, which levies protection from road, railway transit, and other human produced noise, a quiet area in agglomeration is an area that enjoys the foremost level of environmental protection from noise. Quiet areas are generally spaces used for leisure, socialising, recreation, maintaining a link with nature, etc.: activities that add to the human well-being, thus deserving special protection. Epi Spektrum Ltd. has a plethora of experience when it comes to these special zones, as it has prepared numerous expert ground works for determination of quiet areas, and participated in the preparation of spatial planning acts from a noise protection point if view for multiple Slovenian municipalities.