4.15 Sulphated ash
When tested according to 5.16 the amount of sulphated ash shall be as given in Table 3.
(Table 3 — Sulphated ash for different materials)
| Material | Sulphated ash |
| Absorbent cotton gauze | shall not exceed 0,40 % |
| Absorbent cotton gauze Type 13 light | shall not exceed 0,75 % |
| Absorbent cotton and matt viscose ribbon gauze | shall not exceed 1,20 % |
| Absorbent cotton and lustrous viscose ribbon gauze | shall not exceed 0,45 % |
5 Test methods
5.1 General
All tests shall be performed with the material in its final form i.e. sterile or non-sterile.
All reagents used shall be of analytical grade.
NOTE The preparation of test solution S is given in annex B.
5.2 Fibre identification
5.2.1 Absorbent cotton gauze and absorbent cotton ribbon gauze
5.2.1.1 Reagents
a) Zinc chloride solution, iodinated: Dissolve 20 g ± 0,5 g of zinc chloride and 6,5 g ± 0,1 g of potassium iodide in 10,5 ml $\pm \ 0 , 1$ ml of water. Add $\hphantom { - } 0 , 5 \ g \texttt { \pm } 0 , 0 5 \ g$ of iodine and shake for 15 min. Filter if necessary. Store protected from light.
b) Zinc chloride-formic acid solution: Dissolve 20 g ± 0,5 g of zinc chloride in 80 ${ \mathfrak { g } } \pm { \mathfrak { 1 } } { \mathfrak { g } }$ of an 85 % m/V solution of anhydrous formic acid.
5.2.1.2 Tests
Untwist a few threads in the warp and in the weft to free a few of the fibres to be examined and carry out IDENT tests A, B and C.
IDENT A: When examined under a microscope, the cotton fibre shall be flat, ribbon-like, 10 µm to 40 µm wide, with thickened ends and an irregularly shaped lumen.
IDENT B: When treated with iodinated zinc chloride solution, the fibres shall become violet.
IDENT C: To 0,1 g ± 0,05 g fibres add 10 ml ± 0,1 ml of zinc chloride-formic acid solution. Heat to $4 0 ~ ^ { \circ } \mathsf { C }$ and allow to stand for 2,5 h, shaking occasionally.
5.2.2 Absorbent cotton and viscose ribbon gauze
5.2.2.1 Reagent
Hydrogen peroxide solution, dilute: Contains not less than 2,5 % m/m and not more than 3,5 % m/m of hydrogen peroxide in water.
Licensed Copy: Shandong University User, Shandong University , Tue Sep 27 05:04:51 BST 2005, Uncontrolled Copy, (c) BSI
EN 14079:2003 (E)
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