Application
     The FSSU-24 (24-Box Frozen Specimen Shipping Unit for Infectious Substances) is a replacement for the FSSU-21. Its design presented many engineering challenges. The FSSU-24 needs to accomodate 1,944 cryovials in 81-grid freezer boxes that meet regulatory design criteria, survive rod puncture and five 30-ft drops with absolutely no leakage, provide three+ days of refrigeration via dry ice to maintain specimens at or below -40 degrees C, be safely used by gowned/gloved/suited clinical personnel, withstand an internal pressure differential of 95 kPa, and be easy/inexpensive to fabricate, lightweight, durable, rugged, and reusable.

Solution
     Heritage Packaging was contracted to design the flexible, two piece, secondary package. This bag is designed for simple and efficient loading by fully gowned and gloved personnel. Adhesive is employed as the primary closure method and a secondary sleeve is used to ensure a secure closure. The bag is leakproof and airtight after it is closed. The bag can withstand a 95 kPa internal pressure differential without rupturing. Thus, high altitude uncompressed shipment of the entire unit is possible.

Results
     Substantial testing performed by USAMC LOGSA Packaging, Storage & Containerization Center, Tobyhanna, PA revealed that the two piece bag designed and produced by Heritage Packaging met and exceeded all design specifications. Additionally, the package won the 2003 NIPHLE Design Competition "Excellence Award" and was the "Long Life Packaging'" runner up.