The role of suspended ceilings in features WELL verifications and ISO 22955:2021 requirements

The acoustics comfort in workplaces, like offices, guarantee the wellness of the workers providing concentration and productivity. There are recent standards like ISO 22955:2021, Acoustics – Acoustic quality of open office spaces and voluntary point protocols like WELL certification (WELL V2 – Sound) wrote in the USA, that give some guidelines to reach the acoustic comfort through a right design of the environments. The main motivation of this study is grown from the fact that sometimes the big companies of designer find themselves working, at the request of the client, with WELL, just because it is a voluntary point protocol, and this is the reason why it may be favoured with respect to the ISO 22955:2021 and its limits. Not always, the criteria they define are applicable, especially where there is a high presence of architectural constraints and the last majority of interventions are rehabilitation works. In this thesis, the preliminar analysis is carried out through different environment configurations defined according to standards and protocols requirements (state of art) and literature (systematic review). A deeper analysis is performed through in situ case studies in order to have a global overwiev of the existing Open Plan offices. The environments taken into account do not have furniture and the acoustic treatment applied only to ceiling, in order to consider the ISO 22955:2021 precondition. These requirements can be mutually independent, but they were linked together to develop a comparison and verify their applicability. The analized parameters look at the Lombard effect - the involuntary tendency of the speaker to increase the vocal effort, while speaking in loud noise – with the aim of ensuring the acoustic comfort in Open Plan offices.