Psychoacoustic Evaluation of Rock Crushing Plant Noise

The rock crushing is a process, where large pieces of rock are crushed into aggregate of various sizes and compositions. The process is carried out in 2 or 3 different phases: primary, secondary and tertiary phase. The process generates impulse, periodic and broadband noise components. Methods to evaluate the effects of the industrial noise, including rock crushing noise are included in the Nordtest methods ACU 112 [1]. At EU level the environmental noise is assessed at EU legislation [2], and methods to evaluate environmental and crushing noise are in standards [3,4]. There are also several national Finnish studies [5,6], guidelines and statutory decrees for crushing noise (such as VNA 800/2010) but currently the most of them refer to statutory decree VNA 993/1992 concerning the environmental noise levels. Currently, also the CEN working group CEN/TC 151 WG9 (Machines and plants for the production of cement, lime, and gypsum, including crushing, screening, sizing and recycling Safety) is preparing the noise measurement test code for crushing and screening equipment. However, the motivation of this study is to begin to establish a link from noise and sound quality properties to relevant sound absorption and insulation materials and structures. For this goal more information about current situation is needed. To get the data, work begun with the recording and the analysis of a rock crushing station noise. 2. Setup and methods