Like many other premises in education centers, canteens are spaces of everyday life in which the reverberation should be limited to control ambient sound levels, for the well being of occupants that are both users and service staff. It is often necessary to use in such cases special equipment in terms of architectural acoustics to ensure the habitability requirements for those spaces to which are applicable specific regulatory provisions related to noise limitation.
The indicators of the acoustic performance of a space dedicated to the canteen are mainly:
- the reverberation time (usually expressed in seconds) i.e. the time required for the sound level existing in a room to decrease by 60 dB when the noise source (e.g. an electroacoustic generator [1]) is instantly interrupted
- the spatial decay rate (in decibels) i.e. the slope of the spatial sound decay curve in a given distance range, when the distance to the source (e.g. an electroacoustic generator [1]) doubles
There is no acoustic environment of an appropriate quality without satisfactory values for these 2 physical quantities which condition - all at the same time -:
- the intelligibility of speech (without which one must raise one's voice - even shout - to be heard, which is counterproductive, if everyone does the same): for speakers seated at the same table
- the discretion of conversations (for canteen users seated at adjacent tables or even further away)
- the ambient noise level
The implementation of sound absorbing claustras (which combine various functionalities which are very useful in such contexts), is often a convenient mean of contributing to the reduction of reverberation and the propagation of noise in a canteen.
ITS will participate in the acoustical treatment of a canteen by selling absorbing claustras near Rouen (France, Haute-Normandie region, Seine Maritime county).
Given the annoyance felt by the occupants that led to consider soundproofing works, a reduction of the reverberation time has made necessary the installation of products and construction systems having acoustic performance namely for medium and high frequencies.
Were therefore considered when sizing soundproofing equipment for this canteen:
- acoustical screens (absorbing claustras) made of a high density made of a high density mineral wool and of a suitable surfacing (fabric) allowing acleaning with a wet cloth (tailor made, with base) what is a ususal solution in the field of sound insulation in buildings as practiced by ITS.
No doubt that the implementation of those acoustical screens will improve the acoustic comfort of the canteen and will participate in its decoration.
Acoustical treatment of canteens (e.g. for schools, universities, companies) is a recurring subject of engineering and works for ITS, which, in other contexts, can also base solutions for improving the acoustic situation on use of absorbent wall or ceiling coverings, depending on the results of the reverberation study of such premises carried out on a case-by-case basis.
[1] with regard to the measurements that can be made on site by ITS, for the purposes of carrying out a diagnosis prior to seeking improvement in the situation which will thus have been observed and analyzed (once the results of the measurements have been compared with reference values, in general depending on the use of the room and its volume)