----------------------+-------+-------+-------+-------+-------+------ Class | 1. | 2. | 3. | 4. | 5. | 6. ----------------------+-------+-------+-------+-------+-------+------ Mean tearing length | | | | | | in metres | 6,000 | 5,000 | 4,000 | 3,000 | 2,000 | 1,000 | | | | | | Elasticity per cent. | 4 | 3·5 | 3 | 2·5 | 2 | 1·5 | | | | | | Resistance to folding | | | | | | (Schoppers' method, | | | | | | number of foldings) | 190 | 190 | 80 | 40 | 20 | 3 ----------------------+-------+-------+-------+-------+-------+------ The tests for tearing length, resistance to folding, elasticity, etc., are made in air showing relative humidity of 65 per cent. The calculations for tearing length are made on strips of paper dried at 100° C. _(C) Classification according to Use._ ------+-------------------+------+----------+-----------+--------------- | | | | | Weight of | |Fibre.| Strength.| Size of +-------+------- Class.| Uses. |Class.| Class. | Sheets. | 1,000 | 1 Sq. | | | | Cm. |Sheets.| Metre. | | | | | Kg. | Grms. --+---+-------------------+------+----------+-----------+-------+------- 1 | Writing papers for | | | | | | important documents | 1 | 1 | 33 × 42 | 15 | -- | | | | | | | Paper for State | | | | | | documents | 1 | 1 | 26·5 × 42 | 12 | -- | | | | | | 2 | Paper for registers, | | | | | | account books, | | | | | | and ledgers-- | | | | | | | | | | | | (_a_) First quality | 1 | 2 | 33 × 42 | 14 | -- | | | | | | | (_b_) Second quality | 1 | 3 | 33 × 42 | 13 | -- | | | | | | 3 | Documents intended to | | | | | | be preserved longer | | | | | | than ten years-- | | | | | | | | | | | | (_a_) Foolscap paper | 2 | 3 | 33 × 42 | 13 | -- | | | | | |