Because of the excellent acoustic properties of fibre reinforced concrete pipe, the use of FRC™ pipes in suspended applications significantly reduces hydraulic noise emitted from pipeline flow.

Testing carried out at the Queensland University of Technology showed that the 'pseudo STC' rating for FRC™ pipes is 12dB (A) quieter than for PVC pipes. The pseudo STC rating was calculated using measured differences in A- weighted 1/3 - Octave Band Levels at frequencies of 180 Hz and above for radial transmission of sound through each pipe.

A difference of 10dB (A) is equivalent to sound appearing half as loud. Therefore, assuming a constant internal noise source, FRC™ pipes are half as loud as PVC pipes. The acoustic properties may be taken as follows:

Sound Absorption Co-efficient
0.02 at 100 Hz
0.02 at 500 Hz
0.03 at 2000 Hz

Sound Attenuation
12mm wall thickness Š 31dB (A)
18mm wall thickness Š 33dB (A)
30mm wall thickness Š 35dB (A)
42mm wall thickness Š 37dB (A)