278.5 g/kg = 279.865 PSU
| g/kg | PSU |
|---|---|
| 263.5 g/kg | 264.791 |
| 268.5 g/kg | 269.816 |
| 273.5 g/kg | 274.84 |
| 278.5 | 279.865 |
| 283.5 g/kg | 284.889 |
| 288.5 g/kg | 289.914 |
| 293.5 g/kg | 294.938 |
278.5 g/kg = 279.865 PSU
1 g/kg ≈ 1.0049 PSU · 1 mg/L ≈ 0.001 PSU · 1 ppm ≈ 0.001 PSU (dilute aqueous approximation)