Whether it is a school, university, company or community restaurant (without forgetting the ordinary canteen of non-commissioned soldiers and the officers' mess), lowering the sound level of a canteen is necessary when it is expected for such a space that it allows its users not only to eat, but also to take advantage as fully as possible of a time of rest and exchange punctuating their day.
However, the sound environment of a canteen can be negatively impacted by various factors :
- the acoustic quality of the collective catering room, which is inappropriate if it is insufficiently provided with sound-absorbing (in particular: at medium and high frequencies, corresponding to the sound emissions of human speech) materials in sufficient quality and/or quantities ; the presence of tiled floors often leads to accentuating the noise of users when they move around (footsteps, chair movements e.g. when arriving and leaving the table, without forgetting the rolling of trolleys where applicable) or when handling table utensils (including: when clearing trays if it is a self-service canteen)
- the layout of the space :
- the arrangement of tables, which can be problematic if nothing is sufficiently opposed to the propagation of noise (e.g. conversation) from one table to neighboring tables (in addition to the acoustic quality of the room mentioned above, the distance between tables and the presence of obstacles influence this)
- the (undesirable) proximity of some tables of noisy equipment e.g. self-service displays and refrigerated cabinets
- noise emissions (which must be limited) from air conditioning network supply and return vents, which impact a large number of tables, especially when they are well distributed
Thus, when the reverberation of the collective catering room is too high, the background noise level being too high - a fortiori if amplified due to one of the aggravating circumstances mentioned above - an escalation phenomenon occurs for what concerns conversations: everyone, wishing to be heard better, raises their voice, contributing to the ambient hubbub (what is sometimes referrred to as the cocktail effect or the “Lombard” effect).
As in the context of other actions in relation to sound insulation in buildings for other spaces, a lowering of the sound level in a canteen can be obtained by means of acoustic screens :
- when lined (a fortiori : on both sides) with sound-absorbing materials, acoustic screens help reduce reverberation in the dining room; their presence can thus compensate (at least: partially) the deficit of surfaces sufficiently absorbing sound in the room in general, and in particular in the environment close to certain less well-off tables (e.g. with ceiling of insufficient acoustic performance or installed with a height being too large, with impossibility of installing wall linings due to the presence of bay windows)
- when comprising (between the 2 seenable faces) materials attenuating the sound transmission (which can be obtained by the interposition of a core e.g. wood, gypsum, steel if the lining material itself does not have a sufficient mass density), acoustic screens contribute to the increase in spatial sound decay (i.e. the reduction in noise propagation) which is beneficial for the preservation both of the privacy of conversations at a given table, and of the tranquility at neighboring tables
As part of a noise reduction initiative, ITS participated in lowering the noise level in a canteen in the Paris region (France) by marketing acoustic screens.
There is no doubt that the acoustic comfort of the users of this canteen will thus be increased, the habitability being also improved with regard to the decoration in which the elegantly designed acoustic screens will actively participate (one color has been chosen from a wide range).