Suspended from the ceiling, these types of cleanrooms are easily expanded or shrunk as needed over time.
The flexibility of hanging the cleanroom from the ceiling joists is that you can always make changes to your cleanroom(s) as needed.
Ceiling Suspended Softwall Cleanrooms are easy are modular, easily being changed in dimensions over time.
ISO Clean Room Classifications (ISO 14664-1)
Federal Standard 209E (USA) Clean Room Classifications (cancelled in 2001)