Air bag deployment apparatus for vehicle seat

An air bag deployment apparatus for a seat back (14) includes a support bracket (40) and a strap (58). The support bracket (40) has a reaction surface (52) which extends rearwardly of an inflator (44) of an air bag module (38). The strap (58) is sewn at one end onto a trim cover (20) inside a frangible seam line (32) and mounted at the other end to a frame (16). The reaction surface (52) limits forward displacement of a rear portion of the strap (58).