Once all the sheets had been treated, they just needed rehousing. The sheets could not be put back into their original boxes because they were no longer suitable in terms of their size and shape. Also, it was felt that the boxes were housing too many sheets to a box.
For ease of handling, it was decided that the sheets should be stored in Clamshell style boxes with, on average, six to a box. The sheets would also need to be interleaved to stop them catching on each other. The interleaving material needed to be something thin and flexible that would mould to the shape of the sheets, so reducing the risk of extra bulk, but also smooth surfaced so the sheets won’t catch on it. It will also act as a support for each sheet when moving them in and out of the boxes.
Tyvek® was chosen for the job as it fits all these qualities and is chemically inert.