How to reduce noise in a canteen? This is the question faced by many managers and operators of collective dining rooms, in a context of hosting of young children, or of schools, of university restaurants or of corporate restaurants.
Indeed, a canteen is often a noisy place, because of the manipulation by its users of the table art accessories (e.g. plates, glasses, cutlery), and furniture items (e.g. chairs) and also because of the conversations of guests, sometimes animated, a fortiori if they are eager to be noticed or simply to be understood, while they have difficulties for that because of the sound competition that is made by others.
In relation to this problem, the consideration of the effect of the reverberation of the local is primordial, in relation to the reflection of sounds on hard surfaces, which thus contribute to the increase of ambient sound levels.
In order to avoid noise increase in a canteen, it is necessary to install sound-absorbing materials, i.e.materials limiting such acoustic wave reflections, for a sufficient percentage of the surfaces delimiting the space considered (e.g. walls, ceiling) depending on its volume.
Of course the frequency range in which these materials are intrinsically effective in terms of acoustics must include the frequencies corresponding to the human voice: the materials with an absorption coefficient close to 100% in the frequency range with octave central frequencies 500 Hz and 2000 Hz generally meet this requirement.
Depending on the particular context of each project, one or more forms of implementation of such sound-absorbing materials may be preferred or sometimes combined to reduce noise in a canteen: in the form of suspended ceiling tiles or baffles, in the form of wall linings, in the form of screens movable (on legs or on wheels) or stationnary.
How to reduce noise
In any case, the choice of materials must meet the strict conditions for reaction to fire (with respect to blaze risks) and the requirements for decoration also occupy a prominent place among the selection criteria, just as the possibilities for supply and installation.
With a choice of a suitable acoustic treatment system, a canteen can be (or, in the case of a renovation project: can become) a space that is comfortable enough to allow its users to recover, what is obviously not the least of the promises associated with such a place of life.
Unless the noise from Heating Ventilation Air Conditioning (HVAC) installation terminals is a problem, because its level is too high and it then affects the tranquility of the occupants.
If this is the case, it is necessary to consider the insertion, in the aeraulic network, between the source of noise (often constituted by a fan) and the air diffusion openings, of devices referred to as "silencers" which must be carefully sized to allow the necessary compromise between acoustical and aerodynamic performance, sometimes antagonistic.
To reduce noise in a canteen, one can sollicit Isolation Technology Services (ITS), which can perform acoustic measurements on site or perform its work based on drawings, and suggest improvement opportunities with the selection or with the defintion of technical solutions being appropriate for each situation.
This also applies to other similar premises: collective dining rooms, company restaurants, cafeterias, refectories.