u2033 laminated foil packs each containing a sealed non woven polyethylene tyvek u00ae porous pouch filled with different combinations of paraformaldehyde and silica gel as outlined in table iv the foil pack containing the tissue adhesive formulation the porous pouches having the different combinations of paraformaldehyde and silica gel average particle size lt 100 micron and in selected cases a spore strip for use as a primary control were purged with nitrogen heat sealed and sterilized under typical rcs conditions as described in example 1 a number of packages were made without incorporating the pouch for use as secondary controls the compositions of the different pouches used in the rcs study of example 4 are described in table iv the preparation of the specific groups of pouches is outlined below two sets of packages were prepared the first and second sets were prepared using 1 to 5 and 1 to 10 weight ratio of paraformaldehyde to silica gel respectively the weight of the powder mixture for the first and second set was about 222 and 605 mg respectively all packages were purged with nitrogen and sealed the sealed packages were sterilized by irradiation using about 5 kgy of gamma radiation details of the formaldehyde testing and response of the spore strips to rcs processes using the different package inserts are described in examples 5 and 6 respectively testing for formaldehyde residue in packages ii a and ii b containing tissue adhesives of example.