| SAR values | Sodium hazard class | Remark | Sample |
| <10 | S1 | Excellent | 0.5 to 9.90 all sample |
| 10 - 18 | S2 | Good |
|
| 19 - 26 | S3 | Doubtful/fair poor |
|
| >26 | S4 and S5 | Unsuitable |
|