Active bolster with active vent for load management

A method of actively venting an active bolster in a vehicle, wherein the bolster includes a bladder having a front wall and a back wall defining an internal cavity for receiving inflation gas from a gas source during a crash event of the vehicle, the method comprising the steps of:

• configuring a vent in the bladder to provide a first flow coefficient when a pressure difference across the vent is below a first predetermined value and a second flow coefficient when the pressure difference is greater than or equal to a second predetermined value, wherein the second flow coefficient is nonzero and less than the first flow coefficient, and wherein the second predetermined value corresponds to a heavy impact occurring against the bladder when inflated;
• initiating a delivery of the inflation gas into the bladder in response to the crash event, wherein the inflation gas flows out of the vent according to the first flow coefficient during the initial delivery of inflation gas to inflate the bladder;
• and
• the vent automatically responding to an impact against the bladder by venting the inflation gas at the second flow coefficient when the pressure difference rises to the second predetermined value.