DRAFT TANZANIA STANDARD  
                           MEDC2 (5000) P3  - STEEL  WOOL SPECIFICATION  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
©TBS 2017                                                                                                                        First  Edition  
 
 SPECIFICATION FOR COMMERCIAL STEEL WOOL  
1. Scope:  Cover the requirements for commercial steel wool of different grades.  
 
2. Grades:  The commercial steel wool shall be of the following grades,  
 Grade 0000 (Super fine)  
 Grade 000 (Extra fine)  
 Grade 00 (Very fine) 
 Grade 0 (Fine)  
 Grade 1 (Medium)  
 Grade 2 (Coarse)  
 Grade 3 (Very coarse)  
 
3. Width of Steel Wool Fibres - Shall be in accordance with Table 1, when tested as in 7.1.  
 
4. General Requirements:  
4.1. Individual fibres shall have uniform sharp cutting edges and the edges of fibres shall not 
be blunt, when examined under a microscope of magnification 50X.  
 
4.2. The length of the fibres shall be such that wool will cling together in handling without 
excessive unravelling.  
 
4.3. Finished wool shall present a smo oth uniform appearance. The fibres shall be free from 
saw - teeth, ruggedness spirals or whirls, when examined under a magnification of 50X.  
 
5. Material - Steel wool shall be produced from suitable carbon steel or alloy steel meeting the 
requirements laid down  in 7.4 . 
 
6. Manufacturing - Steel wool shall be of uniform having width of steel wool fibres as per Table 
1. long fibre strands of steel having sharp, smooth cutting edges and shall be free from chips, 
short ends and materials other than steel fibres, ex amined under a magnification of 50X.  
 
7. Tests:  
7.1 Width of fibre  - A specimen of 20X fibres shall be selected at random from a lot. Each 
fibre shall be measured under a 50X magnification microscope, graduated in micrometres. 
Not more than one fibre in each specimen shall have a value less than the value specified in 
column 3 of Table 1.  Not more than one fibre in each specimen shall have a width greater 
than the values specified in column 4 of Table 1 and if this one fibre has width greater than 
the values specified in column 5 of Table 1 the specimen shall be declared as fail.  
 
7.2 Ducti lity - A single fibre of each grade of steel wool shall be capable of winding in a 
single loop tightly around the mandrel of size 1.5mm in diameter.  
 
7.3 Moisture and Oil Content  - The loss in mass of a 50g sample of steel wool after drying in 
an oven at 1200C for an hour shall not exceed 1.5 percent.  
 
7.4 Corrosion Resistance :  
 7.4.1 For Steel Wool  ( used for filteration purposes)  - Prepare a nitric acid solution by 
 adding 5 ml concentrated nitric acid and 95 ml of distilled water. Put two drops of this  
 solution on a compressed tuft of the steel wool and observe for any evidence of  corrosion 
 attack. Steel wool shall not show sign of corrosion attack.    
 TABLE 1. Width of steel wool fibres  
 
 
Grade  
  
Mean Width of 
Fibre  
 m  
Not more than 
5 percent 
Under  
 m 
  
Not more than 
5 percent Over  
 m 
  
Not Fibre to 
Exceed  
 m 
 
 
(1) 
  
(2) 
  
(3) 
  
(4) 
  
(5) 
 
 
0000  
000 
00 
0 
1 
2 
3 
  
15.25  
20.35  
30.50  
50.75  
50.100  
100.150  
150.250   
5 
5 
5 
10 
15 
25 
50  
75 
100 
125 
200 
250 
350 
450  
150 
200 
250 
300 
400 
635 
1000  
 
7.4.2 For steel wool (used for other purposes except filteration ) - A tuft of steel wool shall 
be tightly compressed in a ball shape about 20mm in diameter and then slightly flattened. Dip 
a small sheet of white blotting paper in distilled water and then remove from water, shaking off 
the excess water. Place it at the bott om of a glass container. Place the wool specimen on top 
of the blotting paper and cover the container. The temperature of the container shall be 
maintained at 27 ± 2.5ºC for a period of 5 hour. Steel wool shall not show sign of corrosion 
attack.  
 
8. Sampling:  
8.1 Unless otherwise agreed between the supplier and the purchaser, the procedure as given 
in IS 2500 (part 1) - 1973  Sampling inspection tables Part 1 Inspection by attributes and by 
count of defects (first revision)  shall be followed for sampling inspec tion. The sampling plan 
and inspection level as given in 8.2 and 8.3 shall be followed.  
 
8.2 For inspection of which of fibres, cutting edge of fibres and foreign materials in fibres, the 
sampling plan with inspection level II and acceptance quality level (AQL). 4 percent given in 
table 1 and 2 of ISO 2500 (Part 1) - 1973  shall be followed.  
 
8.3 For inspection of ductility, moisture and oil contents and corrosion resistance, the 
sampling plan with inspection level II and AQL 65 percent given in Table 1 and 2 of IS 2500 
(Part 1) - 1973  shall be followed.   
 
9. Packing - The packing of commercial steel  wool shall be as decided by the purchaser and 
the supplier. However, preferred packages shall be 25g pads, 250 and 500g rolls, 5, 10 and 
20kg industrial coils.  
 
10. Marking - The packages shall be marked with the name of the material, the grade, the 
quality, manufacturers' initial trade -mark and month and year of manufacture.  
 
10.1 Certification Marking - Details available with the Tanzania Bureau of Standards . 
 
11. Uses of Steel Wo ol - Intended uses of steel wool are given in Appendix A.   
   
 APPENDIX A  
INTENDED USES OF COMMERCIAL STEEL WOOL  
A-1. Steel wool complying with this specification is intended to be used as an abrasive material for the 
following purposes:  
 Grade 0000  For the rubbing down paint, varnish, polish or shellac before final coat on any 
   surface for quality job.  
 Grade 000  For work on anodized surfaces and rubbing down paint, varnish, etc, also on 
   furniture before polishing and for aluminium and aluminium  utensil. In dairies, 
   for bottles and stainless steel equipment.  
 Grade 00  For polishing of surfaces and household uses.  
 Grade 0  For polishing and buffing surfaces.  
 Grade 1  For cleaning of metal surfaces and light stripping of floor waxes and polishes , 
   and for the preparation of wood surfaces for first coats or fillers.  
 Grade 2  For general abrasive cleaning, for example, removal of rust and old paint, 
   and rapid stripping of floor waxes and polishes.  
 Grade 3  For heavy abrasive cleaning, smoothing of rough surfaces. Also for cleaning 
   of rubber mould in tyre factories, cleaning of bottoms of ships.  
 
A-2. Steel wool of grades 1, 2 and 3 also meeting the requirements of 7.4.1 are used for filteration 
purposes i n the chemical industry.