Airbag module

An airbag (AB) (10) has an airbag mouth (ABM) (12). A gas generator (GG) (14) with a gas outlet area (GOA) (22) fits completely outside the airbag. Near the ABM, the AB has a tightening strap (26) that is stretched around the GG by means of a tightening device, in order to press the ABM against the GOA so as to form a seal. An independent claim is also included for a method for sealed fastening of a gas generator on an airbag mouth.