See also:

Driver’s SRS frontal airbag
The driver’s SRS frontal airbag uses a dual stage inflator. The inflator operates in different ways depending on the severity of impact. Have the system inspected by your SUBARU dealer immediately ...

System servicing
WARNING ● When discarding a seatbelt retractor assembly or scrapping the entire vehicle damaged by a collision, consult your SUBARU dealer. ● Tampering with or disconnecting the system ...

Example of the type of accident in which the SRS curtain airbag will basically not deploy.
The SRS curtain airbags are not basically designed to deploy if the vehicle pitches end over end. ...