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Last updated March 2004.

Manual Guide No. 14A (1999)

The Air Drying of Wet Files and Sheets.

Before beginning drying procedures, the wet files and sheets should be placed in an area with a low level of humidity and good air movement. The wet file cabinets should be dried as quickly as possible, by mopping up wet spots and through the use of dehumidifiers and fans. Files in the wet area should be checked carefully for mold growth during the drying process.

The main objective in the air drying of wet files and sheets is to remove water as efficiently as possible and, at the same time, contain structure distortion, water staining, and the rusting of staples. Structure distortion (i.e. paper settling into a permanent S shape) can be avoided if the files are not left to dry upright in the cabinet or box. The following procedures assume that the wet files have been removed from the cabinet or box.

Files that are Saturated. Do not attempt to open the file folder. Do not attempt to separate the sheets. Place the saturated file with its contents still in a closed position flat on sheets of scrap absorbent paper, such as unprinted newsprint or blotting paper. To permit water to drain efficiently, press lightly on the file cover stroking from the back to the front edge to squeeze out excess water. Place absorbent sheets of paper, such as paper towel, between the inside of the folder cover and the file contents. The excess water will drain from the file into the paper on the table, and if the file is placed in a moving current of air, it should soon damp-dry to the point where it may be opened for the next step.

Files that are Partially Wet. The file may be carefully opened, taking care to separate the top sheet of its contents from the inside of the file cover. Taking a sheet of polyester film (mylar or similar), begin to peel away each sheet in the folder, using the flat suction of the mylar to lift the wet sheet clear of the sheet below. Lay the wet sheet down onto blotting paper using a rolling motion of the mylar. Repeat the process until the contents of the file are laid out in rows as separate drying sheets. Given good drying conditions, the sheets will dry very quickly, usually in less than 30 minutes.

Handling Large Numbers of Wet Files. The procedure above works extremely well for relatively small numbers of files, but the drying space needed is substantial. If there are several dozen files, a modified approach must be taken. Following Step 1 above, the wet files should laid out with a few sheets of paper towel inserted under the file cover and every ten or so sheets inside the file contents. A fan running at fairly high speed should be played over the wet files and, as the paper towels become saturated, change them for dry ones. Drying is much slower using this approach, and at some point, individual damp files can be taken out of the sequence and opened out for faster drying as in Step 2. However, it is important to stabilize the entire file collection before proceeding to this step.

An important point to remember is that files and their contents must be kept in order, and if a saturated file folder is discarded, a note should be taken of its title and the contents for later replacement.