4.6 Shelving

4.6.1 Material. Today, metal (steel) shelves are generally used. There is no risk in using them for storage of magnetic carriers ( Wooden stacks, preferred in the 1950s and 1960s, are now discouraged as chemical treatment components may interact with audiovisual carriers.

4.6.2 Shelf loads. Shelves must be sufficiently sturdy to carry the load of audiovisual carriers. The approximate weight of 1 metre of carriers including typical containers is:

Replicated 78 rpm (“shellac”) records 25 cm (10”) 72 kg
Replicated 78 rpm (“shellac”) records 30 cm (12”) 92 kg
Vinyl discs 17 cm ( 7”, singles)  21 kg
Vinyl discs 25 cm (10”) 38 kg
Vinyl discs 30 cm (12”)  54 kg
Magnetic tape 13 cm (5”) reels 12 kg
Magnetic tape 18 cm (7”) reels 18 kg
Magnetic tape 27 cm (10.5”) reels/hubs 48/40 kg
Magnetic tape 30 cm (12”) on hubs 50 kg
CDs in boxes (jewel case)  7 kg
Magnetic tape 2” : 30/45/70/90 min 84/114/120/142 kg
Magnetic tape 1” : 75/126 min 75/87 kg
U-matic 22 kg
Half inch format cassettes, average 8 kg
DVDs in boxes 6 kg

4.6.3 Storage position. All carriers, discs, tapes, and any cassettes should be stored upright. For discs, shelf separators should be in a distance of half of the discs diameter. Discs should not be tightly packed, however narrow enough to avoid permanent inclined position. Divisions for tapes are usually the same size of their diameter. During the absence of carriers in use, dummy replacements must be used to maintain upright position until carriers are returned.

Only soft, instantaneous discs, like gelatin or Decelith discs, should be stored horizontally in small piles with not more than 10 in a stack.