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D. Mihajlov et al.
Fig. 4 Graphical representation of the technical room using rock wool for acoustic treatment
Fig. 5 Mounting the rock
wool material at the wall
surface together with a
protection net
• Front plate perforation—19.63%;
• Absorber thickness—75 mm;
• Absorber type—Rock wool with density 50 kg/m
3 or polyurethane foam
30 kg/m
3 ;
• Air gap—25 mm next to the absorber back plate.
If rock wool is used, it is necessary to apply the protection acoustic transparent
net.
The values of the absorption coefficient for the observed material can be seen on
Fig. 8.