Common Salt for Chemical Industries under BIS : IS:797-1982
| Sr.No |
Characteristic |
Requirement for |
| Grade I |
Grade II |
| 1. |
Sodium Chloride (as Nacl)Percent by mass, min. |
99.5 |
98.5 |
| 2. |
Matter insoluble in water percent by mass, max. |
0.05 |
0.2 |
| 3. |
Calcium salts (as Ca)percent by mass, max. |
0.03 |
0.2 |
| 4. |
Magnesium salts (as Mg) percent by mass, max. |
0.01 |
0.10 |
| 5. |
Sulphate (as SO4)percent by mass, max. |
0.2 |
0.6 |
| 6. |
Iron compound (as Fe) ppm max. |
10.0 |
20.0 |
The moisture content shall not be more than 1% by mass for Grade 1 & 4% by mass for Grade II.