Active bolster stress relief vents for failsafe weld protection

An active bolster mounts at an interior trim surface of a passenger compartment in an automotive vehicle. A plastic front wall deploys in a deployment direction toward a passenger in the passenger compartment. A plastic expandable bladder member is joined along an outer perimeter with the front wall by a weld seam to form a bladder. The weld seam has a nominal separation pressure. An inflator couples an inflation gas to inflate the bladder in response to a crash event. The bladder member includes a plurality of vent openings configured to regulate an inflation pressure of the inflation gas during an impact according to a passenger restraint profile. The bladder member further includes at least one stress relief vent comprising a frangible tear seam partially cut into the bladder member configured to tear open at a predetermined pressure between the passenger restraint profile and the nominal separation pressure.