1200+
| Material | Moderately Noisy Office | Quiet Office | Very Quiet Office |
|---|---|---|---|
| Fir Plywood | 3.67″ | 6.67″ | 13.33″ |
| Sand Plaster | 0.2″ | 4.45″ | 8.9″ |
| Glass | 0.13″ | 9.3″ | |
| Dense Concrete | 0.14″ | 4.85″ | 12.2″ |
| Aluminum | 0.13″ | 5.7″ | 11.3″ |
| Steel | 0.0045″ | 0.2″ | 7″ |
| Lead | 0.03″ | 0.135″ | 0.54″ |