# Indoor Acoustic Requirements for Autism-Friendly Spaces
## 2 Materials and Methods
### Real Facility Study on Indoor Sound Field  
In order to apply the literature results, in the present research, a real facility was identified and chosen as a case study. Rooms are furnished taking into consideration only hazardous issues, and walls and floors are realized without considering indoor acoustic problems. Seven different rooms designed for daily-care and apartment groups dedicated to ASD people have been investigated by means of on-site acoustic measurements. Furthermore, by means of numerical simulations, an in-depth investigation and a parametric study have been developed, respectively, focused on indoor sound field and on furniture and sound absorbing panels distribution. The selected structure, inaugurated in 2019, is composed by three floors of 2700 m\({}^{2}\) each. After a major renovation, it became a multipurpose center used for both semi-residential and residential spaces for autistic people. The structure houses a day center for adults and an experimental afternoon center for adolescents, some skills labs, an art workshop, a gym, a conference center, a music room, a canteen, a large kitchen for workshops, and also relaxing and hosting areas for parents. The structure overall design was the product of a doctoral dissertation [66]. The issues of sound insulation and the need to prepare the rooms in such a way that both guests and caregivers are adequately protected from an acoustic point of view were widely considered. As an example, particularly sensitive zones such as those related to individual therapy clinics are located in separate areas from the rest of the building and from the outside. Likewise, noisy spaces such as the gymnasium, soft rooms, and activity rooms such as music and art are located as not to interfere with the therapy and living areas. Thisstructure, particularly recent and suitably designed, therefore represents the ideal starting point for this study. The selected therapy rooms for the analysis are as follows (Figure 2a-d):  
* therapy room no. 1: 10 m\({}^{2}\),
* therapy room no. 2: 21 m\({}^{2}\),
* therapy room no. 3: 6 m\({}^{2}\),
* therapy room no. 4: 12 m\({}^{2}\). Furthermore, three other environments were taken into account: a soft room of 12 m\({}^{2}\) dedicated as aa multisensory environment for the well-being of children and adults (Figure 2e), an atelier of 76 m\({}^{2}\) for an art workshop (Figure 2f), and a bedroom of 16 m\({}^{2}\) related to residential apartments (Figure 2g-h). Rooms for individual therapy present different sizes, featuring (i) an entrance door and no window, (ii) very few pieces of furniture (a table and two chairs and few toys), (iii) lights, and (iv) few sound absorbing panels located on the ceiling. Some therapy rooms also feature glasses behind whom parents or other staff can attend therapy sessions. Rooms are realized using prefabricated traditional sandwich panels (pre-painted sheet metal/insulating material/pre-painted sheet metal type) and are located in an area of the building, which is particularly insulated from external noise (no windows) and from noise coming from inside (Figure 11, Appendix A). Figure 2: Cont. These spaces need to be very quiet because this is one of the important user requirements. Inside each therapy space, a single operator works with a single individual and thus it is of paramount importance that nothing disturbs the quiet relationship and that acoustic requirements related to speech clarity and definition are fulfilled. The soft room is located inside the day-center, equipped with impact resistant layering on the walls (up to about 2.10 m height), resilient flooring, and soft cubes, useful both for playing and limiting patients in particular moments of venting and crisis. In this room, the insertion of acoustic sensors may be useful to recognize events (screams, blows) and activate a process of help request (i.e., alert an additional operator and simultaneously trigger a process of audio-visual support).