The existence of these noise flanking paths is well-known in the architectural acoustics industry. Previous studies by the National Research Council of Canada (NRC) concluded even if
ceiling panels with high transmission loss are used, the attenuation between rooms is limited by such leaks. (R.E. Halliwell and J.D. Quirt’s “through a Suspended whatsapp number database Ceiling,” which appeared in the September 1991 issue of the Journal of Acoustical Society of America, has more information.)
The findings of this earlier phase
of the research program showed typical noise flanking paths in a suspended acoustic ceiling (caused by penetrations for lights and air-distribution devices alone) decreased ceiling attenuation class (CAC) by 10 points. (A piece co-written by this article’s author and A.
Heuer, “Effects of Noise Flanking Paths on Ceiling Attenuation Class [CAC] Ratings of Ceiling Systems and Inter-Room Speech Privacy,” was part of the
Proceedings of Inter-Noise 2015, edited by Courtney need some free time for optimization Burroughs and George Maling.)
CAC is the acoustic metric quantifying the ceiling panel’s sound-blocking performance when the demising wall stops at the height of the ceiling.
A 16-mm (5/8-in.) thick mineral fiber ceiling panel tested at CAC 37, but when four lights, one supply diffuser, and one return-air grille were added to the ceiling system, the value decreased to CAC 27. More importantly, the decrease in performance was not consistent across all frequencies.
flexible ducts, and light fixtures remediated. At left, noise-control measures include an internally lined elbow duct over the return-air grille.
which is more relevant to whether or not speech is intelligible,
CACsystem’—the former philippines numbers being what is tested and reported by
manufacturers for their ceiling panels, and the latter being how the whole ceiling system with common penetrations actually performs.
