An inflator (10) includes a container (12) having a chamber (120). An exit opening (48) is provided in the container (12) and is connected to the chamber (120). A substance (122, 180) is stored in the chamber (120) and is responsive to heat for providing inflation fluid. An igniter (130) is associated with the container (12) and is actuatable to provide combustion products for heating the substance (122, 180). A nozzle (80) is interposed between the igniter (130) and the chamber (120). A passage (90) extends from the igniter (130) and through the nozzle (80). The passage (90) includes a divergent portion (110) for focusing a flow of combustion products from the igniter (130) into the chamber (120).