A single, used bag was received and visually inspected by engineering staff.Inspection revealed a film tear under the right spike port.The tear was jagged and non-linear, approximately 3/4-inch long, and extended from below the tear cap port to the perimeter weld location.A small portion of the tear extended approximately 1/8-inch into the perimeter weld.A capa had previously been issued to investigate film breaks of this nature.A review of the capa investigation indicated failure modes of this type have been reproduced by introducing an air bubble inside the bag prior to freezing.An air bubble could rapidly expand during the thawing process, resulting in a film tear.The evidence observed from the returned sample indicates the likely root cause of the cracked film was the existence of an air bubble in the bag prior to freezing.Precautions for air bubbles inside the bag prior to freezing are addressed in the product ifu's.
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