578.5 g/kg = 581.335 PSU
| g/kg | PSU |
|---|---|
| 563.5 g/kg | 566.261 |
| 568.5 g/kg | 571.286 |
| 573.5 g/kg | 576.31 |
| 578.5 | 581.335 |
| 583.5 g/kg | 586.359 |
| 588.5 g/kg | 591.384 |
| 593.5 g/kg | 596.408 |
578.5 g/kg = 581.335 PSU
1 g/kg ≈ 1.0049 PSU · 1 mg/L ≈ 0.001 PSU · 1 ppm ≈ 0.001 PSU (dilute aqueous approximation)