The sisal is selected according to the length, color and degree of impurities. In order to select by length, the sisal is separated in the following categories:
Long (L): fiber length from 0.90 metes to 1.10 meters;
Medium (M): fiber length from 0.70 meters to 0.90 meters;
Short (S): fiber length from 0.60 meters to 0.70 meters.
Below, you can see how the sisal fiber is categorized by its degree of impurities.
Type 1 DB
Consisting of dry, well-beaten or brushed fibers of a light cream or yellowish color, in a good state of maturity, with normal softness, gloss and strength, spots with little variation in color, maximum humidity of 13.5% ( thirteen and a half percent), loose and clear, free from impurities, pectic substances, plaits, knots, leaf fragments, bark and any other defects. Although the Ministry of Agriculture rules do not provide for any percentage of impurities, the international market accepts and tolerates up to 1% of impurities, given the great difficulty in producing this type of sisal, depending on the extraction conditions in the field.
Type 2 DB
Consisting of dry and well-beaten or brushed fibers, yellowish or brownish in color, with small greenish extensions, in a good state of maturity, with normal brightness and resistance, slightly rough, maximum humidity of 13.5 (thirteen and a half per cent), loose and clear, free from impurities, plaits, knots and shells. Usually this fiber has a percentage of impurities not exceeding 2%. It is tolerable up to 10% of medium fibers (71 - 90 cm).
Type 3 DB
Consisting of dry, well-beaten or brushed fibers, yellowish in color, with a greenish, brownish or reddish tint, in a good state of maturity, with normal brightness and resistance, rough, spots with very sharp variation in color, maximum humidity 13.5% (thirteen and a half percent), loose and clear, free of impurities, plaits, knots and shells. Normally this fiber has a percentage of impurities around 3.5% and has a much more pronounced color variation than sisal type 2. It is tolerable up to 20% of medium fibers (71 - 90 cm).
Type 4 DB
This type of sisal was established according to trade practice. It consists of a sisal that cannot be classified as type 3 because it has a very marked variation in color, size and degree of impurity, but at the same time, as it has a lot of fiber above 60 cm, it cannot be classified as waste.
Like sisal type 4, its concept was established according to trade practice. It consists of a sisal with the same characteristics as type 4 sisal, however, with a higher impurity index and more pronounced color and size variation.
Consisting of uniform light cream colored fibers, in good condition, maximum humidity of 14% (fourteen percent), coming from drying, batting and selection operations, free of foreign materials and knots. Meeting the demands of our customers, our company has developed a bushing selection process to exclude the node. Therefore, the RISANA brand bushing is 100% knot free.