A SAFETY DEVICE IN A VEHICLE

A safety device for a safety device in a vehicle is provided. The safety device (100) comprises a housing (1) having a first end (2) and a second end (3), a piston (4) adapted to fit in the housing (1) and being configured to be moved from a retracted position to an extended position, and a gas generator (15). The piston (4) has a first end forming a pressure surface (6) facing the first end (2) of the housing (1). A gas chamber (8) is formed between the pressure surface (6) of the piston (4) and an inner wall (7) of the housing (1), and the gas generator (15) is situated in the gas chamber (8). The housing (1) comprises at its second end (3) a gas evacuation arrangement (20; 20'; 20") allowing gas generated by the gas generator (15) to be evacuated from the gas chamber (8) in a condition when the piston (4) is situated in situated in a full or substantially full extended position.